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WO2022028236A1 - Method for synthesizing difluoromethane by means of gas phase catalysis - Google Patents

Method for synthesizing difluoromethane by means of gas phase catalysis Download PDF

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Publication number
WO2022028236A1
WO2022028236A1 PCT/CN2021/106982 CN2021106982W WO2022028236A1 WO 2022028236 A1 WO2022028236 A1 WO 2022028236A1 CN 2021106982 W CN2021106982 W CN 2021106982W WO 2022028236 A1 WO2022028236 A1 WO 2022028236A1
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Prior art keywords
difluoromethane
reaction
tower
catalyst
chromium
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PCT/CN2021/106982
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French (fr)
Chinese (zh)
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周黎旸
洪江永
杨波
张彦
施浩进
余慧梅
洪海港
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浙江衢化氟化学有限公司
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Publication of WO2022028236A1 publication Critical patent/WO2022028236A1/en

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C17/00—Preparation of halogenated hydrocarbons
    • C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
    • C07C17/20—Preparation of halogenated hydrocarbons by replacement by halogens of halogen atoms by other halogen atoms
    • C07C17/202—Preparation of halogenated hydrocarbons by replacement by halogens of halogen atoms by other halogen atoms two or more compounds being involved in the reaction
    • C07C17/206—Preparation of halogenated hydrocarbons by replacement by halogens of halogen atoms by other halogen atoms two or more compounds being involved in the reaction the other compound being HX
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/06—Halogens; Compounds thereof
    • B01J27/132—Halogens; Compounds thereof with chromium, molybdenum, tungsten or polonium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/20—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state
    • B01J35/23—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state in a colloidal state
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • B01J37/031—Precipitation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • B01J37/082—Decomposition and pyrolysis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/22—Halogenating
    • B01J37/26—Fluorinating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/34—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation
    • B01J37/341—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation
    • B01J37/344—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation of electromagnetic wave energy
    • B01J37/346—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation of electromagnetic wave energy of microwave energy
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C17/00—Preparation of halogenated hydrocarbons
    • C07C17/38—Separation; Purification; Stabilisation; Use of additives
    • C07C17/383—Separation; Purification; Stabilisation; Use of additives by distillation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C17/00—Preparation of halogenated hydrocarbons
    • C07C17/38—Separation; Purification; Stabilisation; Use of additives
    • C07C17/395—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to a chemical modification of at least one compound

Definitions

  • the invention relates to a method for synthesizing fluorine-containing alkanes, in particular to a method for gas-phase catalytic synthesis of difluoromethane.
  • HFC-32 Difluoromethane (HFC-32), with zero ozone depletion potential (ODP) and 675 global warming potential (GWP), has the characteristics of low boiling point and large cooling coefficient.
  • HFC-32 can be used in a variety of mixed refrigerants. The most commonly used mixed refrigerant is R410a, and it can also be used as a single refrigerant. Its performance is similar to that of R410a, and its COP is comparable to that of R410a. Good availability and cheap price.
  • the disadvantage is that the traditional washing and alkaline washing processes are used, which brings environmental problems.
  • a method for gas-phase catalytic synthesis of difluoromethane comprising the following steps:
  • step (b) the first reaction product obtained in step (a) is entered into the deacidification separation tower to obtain the tower still component and the tower top component;
  • step (d) the mixture material that step (c) obtains enters purification tower, obtains the mixture after purification;
  • step (e) the purified mixture obtained in step (d) enters the light-removing tower, and the tower top obtains the light component, and the tower reactor material is dried to obtain the difluoromethane product.
  • the column reactor component obtained in step (b) is fed into the second reactor, and the same catalyst as in step (a) is used to carry out a catalytic reaction, and the temperature of the catalytic reaction is 250-350 ° C to obtain
  • the second reaction product is sent into the deacidification separation tower.
  • the temperature of the catalytic reaction in step (a) is 200-400° C.
  • the space velocity is 500-3000 h ⁇ 1
  • the molar ratio of hydrogen fluoride and dichloromethane is 10-20:1.
  • the catalyst uses chromium as the main component, and one selected from cobalt, zinc, iron, and gallium is the auxiliary component I, and is selected from aluminum, zinc, iron, nickel, and gallium.
  • auxiliary component II is different from auxiliary component II, the molar ratio of chromium and auxiliary component I is 1:0.02 ⁇ 0.1, and the molar ratio of chromium and auxiliary component II is 1:0.1 ⁇ 0.5.
  • the catalyst is prepared by the following method:
  • step (c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
  • the surfactant in step (b) is polyethylene glycol, and the amount of polyethylene glycol added accounts for 0.1-0.3% of the total moles of Cr 3+ in the reaction solution.
  • the purification tower is filled with a solid acid scavenger and an auxiliary agent
  • the mass ratio of the solid acid scavenger and the auxiliary agent is 1-4:1
  • the solid acid scavenger is The agent is at least one of KOH, Mg(OH) 2 , NaOH, Ca(OH) 2 , Al(OH) 3 , Ba(OH) 2 , Zn(OH) 2 , Fe(OH) 3
  • the auxiliary agent is at least one of phosphoric acid, trisodium phosphate, calcium phosphate, calcium hydrogen sulfite, calcium carbonate and sodium sulfite.
  • the traditional production process of HFC-32 is to use water washing and alkali washing to remove a small amount of acidic substances such as HF and HCl, resulting in a large amount of waste water, and then drying.
  • the purification tower is filled with solid acid scavenger and auxiliary agent, which replaces the traditional water washing and alkaline washing processes, reduces waste water and reduces energy consumption.
  • the catalysts used in the gas phase method in the prior art are all chromium-based, and other components are assisted, and most of them are prepared by a co-precipitation method.
  • the catalyst has a small specific surface area and is easy to carbonize and deactivate.
  • the liquid surface area of the ammonium bicarbonate solution is on the surface of the ammonium bicarbonate solution.
  • the spray feed rate is 10-25ml/min.
  • the obtained ultrafine hydroxide is dried and calcined to obtain chromium oxide powder.
  • the traditional drying method generally uses an oven for drying, which has high energy consumption, low efficiency, and poor effect.
  • the process is simple and the efficiency is high, the gas phase two -step reaction process is adopted, the operation is simple, the reaction conditions are mild, the production process is significantly simplified, and the total conversion rate of CH2Cl2 is 100%.
  • the catalyst has good activity and long service life.
  • the uniformity of the obtained product is good by controlling the concentration of Cr 3+ in the mixed solution and the spray feeding speed on the liquid surface area of the ammonium bicarbonate solution.
  • the specific surface area of the catalyst is increased, and the carbonization rate of the catalyst is delayed; the second-order microwave drying is adopted, which can well control the uniformity of the material during the drying process, and effectively prolong the life of the catalyst.
  • the present invention uses a purification tower filled with solid acid scavengers and auxiliary agents to remove a small amount of acidic substances such as HF and HCl. Compared with the traditional water washing and alkaline washing processes, the purification process significantly reduces waste water and energy consumption. .
  • Fig. 1 is the process flow schematic diagram of the present invention.
  • the raw materials CH 2 Cl 2 and HF enter the first reactor 1 filled with the catalyst through the pipeline 18, and the reaction is carried out under the action of the catalyst.
  • the reaction product of CH 2 Cl 2 and HF is separated into the deacidification separation tower 2 through the pipeline 8 to obtain the mixed components of the tower reactor and the overhead product;
  • the overhead product of the deacidification separation column 2 enters the hydrogen chloride separation through the pipeline 9 Tower 4,
  • the hydrogen chloride gas obtained at the top of the hydrogen chloride separation tower 4 is processed separately, and the mixed components that mainly contain HFC-32, a small amount of HF and a small amount of HFC-23 obtained from the 4 tower stills of the hydrogen chloride separation tower are filled with solid deacidification through pipeline 13.
  • the mixed components of the tower reactor of the deacidification separation tower 2 mainly contain HCFC-31, unreacted CH 2 Cl 2 and HF, which are fed into the second reactor 3 filled with the catalyst through the pipeline 10, and further reacted under the action of the catalyst;
  • the reaction product mainly containing HFC-32, HCl, HF and a small amount of HCFC-31 at the outlet of the second reactor 3 enters the deacidification separation tower 2 through the pipeline 11.
  • Embodiments 1-7 are the preparation examples of catalysts
  • the preparation method of the catalyst is as follows:
  • step (c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
  • step (d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 200W, the second-order power is 200W, and the total drying time of the second-order microwave drying is 0.5 h, after drying, calcining at 400 °C to obtain nano-chromium oxide powder;
  • step (e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain 1# catalyst.
  • the preparation method of the catalyst is as follows:
  • step (c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
  • step (d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 220W, the second-order power is 180W, and the total drying time of the second-order microwave drying is 1.0 h, after drying, calcining at 600 ° C to obtain nano-chromium oxide powder;
  • step (e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 2# catalyst.
  • the preparation method of the catalyst is as follows:
  • step (c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
  • step (e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 3# catalyst.
  • the preparation method of the catalyst is as follows:
  • step (c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
  • step (d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 260W, the second-order power is 140W, and the total drying time of the second-order microwave drying is 0.6 h, after drying, calcining at 600 ° C to obtain nano-chromium oxide powder;
  • step (e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain 4# catalyst.
  • the preparation method of the catalyst is as follows:
  • step (c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
  • step (d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 280W, the second-order power is 120W, and the total drying time of the second-order microwave drying is 0.8h , and calcined at 500 °C after drying to obtain nano-chromium oxide powder;
  • step (e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 5# catalyst.
  • the preparation method of the catalyst is as follows:
  • step (c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
  • step (d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 300W, the second-order power is 100W, and the total drying time of the second-order microwave drying is 1h , and calcined at 700 °C after drying to obtain nano-chromium oxide powder;
  • step (e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 6# catalyst.
  • the preparation method of the catalyst is as follows:
  • step (d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 250W, the second-order power is 150W, and the total drying time of the second-order microwave drying is 0.9 h, after drying, calcining at 600 ° C to obtain nano-chromium oxide powder;
  • step (e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 7# catalyst.
  • the first reactor is filled with 1# catalyst
  • the second reactor is filled with 2#
  • the purification tower is filled with solid acid scavenger NaOH and auxiliary trisodium phosphate
  • the mass ratio of solid acid scavenger NaOH and auxiliary trisodium phosphate is 2 : 1
  • the reaction conditions and the composition of the organic matter at the outlet of the two reactors are shown in Table 2.
  • the first reactor is filled with 3# catalyst
  • the second reactor is filled with 4#
  • the purification tower is filled with the solid acid scavenger Ba(OH) 2 and the auxiliary calcium carbonate described in the solid acid scavenger and auxiliary agent
  • the solid acid scavenger is The mass ratio of the agent Ba(OH) 2 and the auxiliary agent calcium carbonate is 4:1, and the reaction conditions and the organic matter composition of the two reactor outlets are shown in Table 5.
  • the first reactor is filled with 3# catalyst
  • the second reactor is filled with 4#
  • the purification tower is filled with the solid acid scavenger Ba(OH) 2 and the auxiliary calcium carbonate described in the solid acid scavenger and auxiliary agent
  • the solid acid scavenger is The mass ratio of the agent Ba(OH) 2 and the auxiliary agent calcium carbonate is 4:1, and the reaction conditions and the organic matter composition of the two reactor outlets are shown in Table 5.
  • the first reactor is filled with 3# catalyst
  • the second reactor is filled with 4#
  • the purification tower is filled with the solid acid scavenger Ba(OH) 2 and the auxiliary calcium carbonate described in the solid acid scavenger and auxiliary agent
  • the solid acid scavenger is The mass ratio of the agent Ba(OH) 2 and the auxiliary agent calcium carbonate is 4:1, and the reaction conditions and the organic matter composition of the two reactor outlets are shown in Table 5.

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Abstract

Disclosed is a method for synthesizing difluoromethane by means of gas-phase catalysis. The method comprises: (a) introducing difluoromethane and hydrogen fluoride into a first reactor under the action of a catalyst for a catalytic reaction, so as to obtain a first reaction product; (b) introducing the first reaction product into a deacidification separation tower, so as to obtain a tower bottom component and a tower top component; (c) separating hydrogen chloride from the tower top component obtained in step (b), so as to obtain a mixed material containing difluoromethane; (d) introducing the mixed material obtained in step (c) into a purifying tower, so as to obtain a purified mixture; and (e) introducing the purified mixture obtained in step (d) into a light component removal tower so as to obtain a light component at the tower top, and drying the material at the tower bottom, so as to obtain a difluoromethane product. The method has the advantages of a simple process, mild reaction conditions, a good catalyst activity and a long service life.

Description

一种气相催化合成二氟甲烷的方法A kind of method for gas-phase catalytic synthesis of difluoromethane 技术领域technical field
本发明涉及含氟烷烃的合成方法，尤其涉及一种气相催化合成二氟甲烷的方法。The invention relates to a method for synthesizing fluorine-containing alkanes, in particular to a method for gas-phase catalytic synthesis of difluoromethane.
背景技术Background technique
二氟甲烷(HFC-32)，臭氧损耗潜能值(ODP)为零，全球变暖潜能值(GWP)为675，具有沸点低，制冷系数大等特点。HFC-32可用于多种混配制冷剂，最常用的混配制冷剂是R410a，也可以单工质作为制冷剂，性能与R410a相近，COP与R410a相当，GWP只有R410a的1/3，市场可获得性好，价格便宜。Difluoromethane (HFC-32), with zero ozone depletion potential (ODP) and 675 global warming potential (GWP), has the characteristics of low boiling point and large cooling coefficient. HFC-32 can be used in a variety of mixed refrigerants. The most commonly used mixed refrigerant is R410a, and it can also be used as a single refrigerant. Its performance is similar to that of R410a, and its COP is comparable to that of R410a. Good availability and cheap price.
HFC-32工业上有两种生产方法：There are two production methods for HFC-32 in industry:
(1)在锑基催化剂存在下，用HF和二氯甲烷(CH 2Cl 2)进行液相氟化。 (1) Liquid phase fluorination with HF and dichloromethane (CH 2 Cl 2 ) in the presence of an antimony-based catalyst.
(2)在铬基催化剂存在下，用HF和二氯甲烷进行气相氟化。(2) Gas-phase fluorination with HF and dichloromethane in the presence of a chromium-based catalyst.
反应方程式为：The reaction equation is:
CH 2Cl 2+HF→CH 2FCl(HCFC-31)+HCl CH 2 Cl 2 +HF→CH 2 FCl(HCFC-31)+HCl
CH 2FCl+HF→CH 2F 2(HFC-32)+HCl CH 2 FCl+HF→CH 2 F 2 (HFC-32)+HCl
目前，制备二氟甲烷的工业化装置多数采用液相氟化的工艺路线，此技术路线存在设备腐蚀、单个反应器产能低、废催化剂难处理等缺点。而气相氟化的难点是催化剂，也是其核心技术，由于反应温度高，催化剂易结碳而失活。At present, most of the industrial plants for the preparation of difluoromethane adopt the process route of liquid phase fluorination, which has disadvantages such as equipment corrosion, low productivity of a single reactor, and difficult disposal of waste catalysts. The difficulty of gas-phase fluorination is the catalyst, which is also its core technology. Due to the high reaction temperature, the catalyst is easily deactivated by carbonization.
国内外对气相法生产二氟甲烷的催化剂进行了大量研究，目前比较成熟的是以铬或镍为主要活性成分的催化剂，如Cr 2O 3、CrF 3、Cr/C、Ni/AlF 3、Ni-Cr/AlF 3混合催化剂等；或者使用无铬催化剂如CoCl 2/AlF 3，但这些催化剂在使用中稳定性较差，易导致迅速焦化或晶化而失活，从而影响使用寿命。为了克服这一缺陷，常常在氟化过程中通入氯气、氧气或空气，以延长催化剂寿命，不足之处是会生成无用的副产物或导致选择性降低。 A lot of research has been done on catalysts for the production of difluoromethane by gas phase method at home and abroad. At present, the catalysts with chromium or nickel as the main active components are relatively mature, such as Cr 2 O 3 , CrF 3 , Cr/C, Ni/AlF 3 , Ni-Cr/AlF 3 mixed catalysts, etc.; or use chromium-free catalysts such as CoCl 2 /AlF 3 , but these catalysts have poor stability in use and are likely to cause rapid coking or crystallization and deactivation, thereby affecting service life. To overcome this drawback, chlorine, oxygen or air are often introduced during the fluorination process to prolong the catalyst life, but the disadvantage is that useless by-products are generated or the selectivity is reduced.
如美国专利号US4147733，发明名称：氯代烷烃的氟化方法，该发明披露了一种在金属氟化催化剂存在下气相氟化氯代烷烃的方法，其使用负载在载体上的基于铝、镍或铬中的一种或多种的氟化催化剂，如将铬负载在氧化铝上作为氟化催化剂，不足之处 是催化剂稳定性较差，容易失活。Such as U.S. Patent No. US4147733, title of invention: fluorination method of chlorinated alkanes, the invention discloses a method for gas phase fluorination of chlorinated alkanes in the presence of metal fluorination catalysts, which uses aluminum-based, nickel-based materials supported on supports Or one or more fluorination catalysts in chromium, such as supporting chromium on alumina as a fluorination catalyst, the disadvantage is that the catalyst has poor stability and is easy to deactivate.
如中国专利公开号CN1144213A，发明名称：二氟甲烷的生产方法，该申请案公开了一种二氟甲烷的生产方法，使用铬或镍基的本体或载体上的混合催化剂，为了延长催化剂的寿命及减少催化剂的结焦，要在有氯的情况下进行操作。但有氯气存在会生成其它副产物，而且，引入氯气会导致许多不确定的安全隐患。For example, Chinese Patent Publication No. CN1144213A, title of invention: production method of difluoromethane, this application discloses a production method of difluoromethane, using a chromium or nickel-based body or a mixed catalyst on a carrier, in order to prolong the life of the catalyst And to reduce the coking of the catalyst, it is necessary to operate in the presence of chlorine. However, the presence of chlorine gas will generate other by-products, and the introduction of chlorine gas will lead to many uncertain safety hazards.
如中国专利公开号CN1994987A，发明名称：一种二氟甲烷生产工艺，该发明提供一种二氟甲烷生产工艺：原料氟化氢和二氯甲烷按照配比为氟化氢∶二氯甲烷＝1∶1.5～3.0(重量比)分别经过汽化器汽化至70～130℃；通入装有催化剂的氟化反应器中，在压力为0.8～1.6MPa，反应温度为80～140℃下反应；生成的二氟甲烷粗品经过回流塔及回流冷凝器分离；产品经降膜吸收器脱除生成的氯化氢，再经过水洗、碱洗、脱气、精馏后即得到纯品二氟甲烷。不足之处是采用传统的水洗、碱洗工艺，带来环保问题。For example, Chinese Patent Publication No. CN1994987A, the name of the invention: a difluoromethane production process, the invention provides a difluoromethane production process: the raw materials hydrogen fluoride and dichloromethane are hydrogen fluoride: dichloromethane = 1: 1.5～3.0 (weight ratio) are respectively vaporized to 70～130 ℃ through the vaporizer; pass into the fluorination reactor equipped with catalyst, react at the pressure of 0.8～1.6MPa, and the reaction temperature is 80～140 ℃; the generated difluoromethane crude product The product is separated by reflux tower and reflux condenser; the hydrogen chloride generated is removed by falling film absorber, and pure difluoromethane is obtained after washing with water, alkali washing, degassing and rectification. The disadvantage is that the traditional washing and alkaline washing processes are used, which brings environmental problems.
如中国专利公开号CN1150943A，发明名称：二氟甲烷的生产方法，该申请案公开了一种二氯甲烷气相氟化生产二氟甲烷的方法，在有氧气的情况下，在温度330-450℃并用本体或载体上的铬催化剂进行操作，其中催化剂中铬的含量低于20％。不足之处是氟化反应过程中引入氧气易与氯化氢反应生成氯，进而使反应混合物中的氢化物质氯化；除此以外，还易产生水，带来设备腐蚀问题。For example, Chinese Patent Publication No. CN1150943A, title of invention: production method of difluoromethane, this application discloses a method for producing difluoromethane by gas-phase fluorination of dichloromethane, in the presence of oxygen, at a temperature of 330-450 ° C And operate with a bulk or supported chromium catalyst, wherein the content of chromium in the catalyst is less than 20%. The disadvantage is that the introduction of oxygen during the fluorination reaction is easy to react with hydrogen chloride to generate chlorine, which in turn chlorinates the hydrogenated substance in the reaction mixture; in addition, it is easy to generate water, which brings equipment corrosion problems.
发明内容SUMMARY OF THE INVENTION
本发明的目的是针对现有技术的不足，提供一种工艺简单，安全环保，催化剂活性好，寿命长的气相催化合成二氟甲烷的方法。The object of the present invention is to provide a method for gas-phase catalytic synthesis of difluoromethane with simple process, safety and environmental protection, good catalyst activity and long service life, aiming at the deficiencies of the prior art.
为了解决上述技术问题，本发明是通过以下技术方案实现的：一种气相催化合成二氟甲烷的方法，包括以下步骤：In order to solve the above-mentioned technical problems, the present invention is achieved through the following technical solutions: a method for gas-phase catalytic synthesis of difluoromethane, comprising the following steps:
(a)在催化剂作用下，将二氯甲烷和氟化氢进入第一反应器进行催化反应，得到第一反应产物；(a) under the action of a catalyst, dichloromethane and hydrogen fluoride are entered into the first reactor to carry out catalytic reaction to obtain the first reaction product;
(b)将步骤(a)得到的第一反应产物进入脱酸分离塔，得到塔釜组分和塔顶组分；(b) the first reaction product obtained in step (a) is entered into the deacidification separation tower to obtain the tower still component and the tower top component;
(c)将步骤(b)得到的塔顶组分分离氯化氢后得到含二氟甲烷的混合物料；(c) obtain the mixture material containing difluoromethane after the tower top component obtained in step (b) is separated from hydrogen chloride;
(d)将步骤(c)得到的混合物料进入净化塔，得到净化后的混合物；(d) the mixture material that step (c) obtains enters purification tower, obtains the mixture after purification;
(e)将步骤(d)得到的净化后的混合物进入脱轻塔，塔顶得到轻组分，塔釜物料 经干燥，得到二氟甲烷产品。(e) the purified mixture obtained in step (d) enters the light-removing tower, and the tower top obtains the light component, and the tower reactor material is dried to obtain the difluoromethane product.
作为本发明的优选实施方式，将步骤(b)得到的塔釜组分进入第二反应器，使用步骤(a)相同的催化剂进行催化反应，所述催化反应的温度为250～350℃，得到第二反应产物，将所述的第二反应产物进入所述的脱酸分离塔。As a preferred embodiment of the present invention, the column reactor component obtained in step (b) is fed into the second reactor, and the same catalyst as in step (a) is used to carry out a catalytic reaction, and the temperature of the catalytic reaction is 250-350 ° C to obtain For the second reaction product, the second reaction product is sent into the deacidification separation tower.
作为本发明的优选实施方式，步骤(a)所述的催化反应的温度为200～400℃，空速为500～3000h -1，氟化氢和二氯甲烷的摩尔比为10～20:1。 As a preferred embodiment of the present invention, the temperature of the catalytic reaction in step (a) is 200-400° C., the space velocity is 500-3000 h −1 , and the molar ratio of hydrogen fluoride and dichloromethane is 10-20:1.
作为本发明的优选实施方式，所述催化剂以铬为主要组分，选自钴、锌、铁、镓中的一种为辅助组分Ⅰ，选自铝、锌、铁、镍、镓中的一种为辅助组分Ⅱ，且辅助组分Ⅰ与辅助组分Ⅱ不同，铬与辅助组分Ⅰ的摩尔比为1:0.02～0.1，铬与辅助组分Ⅱ的摩尔比为1:0.1～0.5。As a preferred embodiment of the present invention, the catalyst uses chromium as the main component, and one selected from cobalt, zinc, iron, and gallium is the auxiliary component I, and is selected from aluminum, zinc, iron, nickel, and gallium. One is auxiliary component II, and auxiliary component I is different from auxiliary component II, the molar ratio of chromium and auxiliary component I is 1:0.02～0.1, and the molar ratio of chromium and auxiliary component II is 1:0.1～ 0.5.
作为本发明的优选实施方式，所述催化剂是按以下方法制备得到的：As a preferred embodiment of the present invention, the catalyst is prepared by the following method:
(a)按比例称取铬、辅助组分Ⅰ与辅助组分Ⅱ的化合物，配制成混合溶液；(a) weigh the compounds of chromium, auxiliary component I and auxiliary component II in proportion to prepare a mixed solution;
(b)将上述混合溶液通过喷雾雾化后喷向碳酸氢铵溶液中反应，并同时加入表面活性剂，控制反应终点pH值为8.0～9.0，得到反应液；(b) above-mentioned mixed solution is sprayed in ammonium bicarbonate solution by spray atomization to react, and simultaneously adds surfactant, and controls the pH value of reaction end point to be 8.0～9.0, obtains reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行微波干燥，煅烧，得到纳米氧化铬粉体；(d) microwave drying and calcining the ultrafine hydroxide obtained in step (c) to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a catalyst.
作为本发明的优选实施方式，步骤(a)中所述的铬、辅助组分Ⅰ与辅助组分Ⅱ的化合物为硝酸盐或氯化物，所述混合溶液中Cr 3+的浓度为0.1～0.2mol/L。 As a preferred embodiment of the present invention, the compounds of chromium, auxiliary component I and auxiliary component II described in step (a) are nitrates or chlorides, and the concentration of Cr 3+ in the mixed solution is 0.1-0.2 mol/L.
作为本发明的优选实施方式，步骤(b)中所述的反应的温度为50～80℃，反应的时间为30～120min，所述的碳酸氢铵溶液的液面面积上喷雾加料速度为10～25ml/min，所述的碳酸氢铵溶液的初始浓度为1.0～1.5mol/L；As a preferred embodiment of the present invention, the temperature of the reaction described in the step (b) is 50 to 80° C., the time of the reaction is 30 to 120 min, and the spray feed rate on the liquid surface area of the ammonium bicarbonate solution is 10 ～25ml/min, the initial concentration of the ammonium bicarbonate solution is 1.0～1.5mol/L;
作为本发明的优选实施方式，步骤(b)中所述的表面活性剂为聚乙二醇，所述聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.1～0.3％。 As a preferred embodiment of the present invention, the surfactant in step (b) is polyethylene glycol, and the amount of polyethylene glycol added accounts for 0.1-0.3% of the total moles of Cr 3+ in the reaction solution.
作为本发明的优选实施方式，步骤(d)中所述的微波干燥为二阶微波干燥，所述二阶微波干燥的第一阶功率为200～300W，第二阶功率为100～200W，所述二阶微波干燥的总干燥时间为0.5～1h，所述的煅烧的温度400～700℃。As a preferred embodiment of the present invention, the microwave drying in step (d) is second-order microwave drying, and the first-order power of the second-order microwave drying is 200-300W, and the second-order power is 100-200W, so The total drying time of the second-stage microwave drying is 0.5-1 h, and the calcining temperature is 400-700°C.
作为本发明的优选实施方式，所述的净化塔中装填有固体除酸剂和助剂，所述的固体除酸剂和助剂的质量比为1～4:1，所述的固体除酸剂为KOH、Mg(OH) 2、NaOH、 Ca(OH) 2、Al(OH) 3、Ba(OH) 2、Zn(OH) 2、Fe(OH) 3中的至少一种，所述的助剂为磷酸、磷酸三钠、磷酸钙、亚硫酸氢钙、碳酸钙、亚硫酸钠中的至少一种。 As a preferred embodiment of the present invention, the purification tower is filled with a solid acid scavenger and an auxiliary agent, the mass ratio of the solid acid scavenger and the auxiliary agent is 1-4:1, and the solid acid scavenger is The agent is at least one of KOH, Mg(OH) 2 , NaOH, Ca(OH) 2 , Al(OH) 3 , Ba(OH) 2 , Zn(OH) 2 , Fe(OH) 3 , the said The auxiliary agent is at least one of phosphoric acid, trisodium phosphate, calcium phosphate, calcium hydrogen sulfite, calcium carbonate and sodium sulfite.
目前，气相法合成HFC-32的工业化装置采用一个反应器，未反应的CH 2Cl 2、中间产物HCFC-31返回到反应器，造成反应器负荷高、产能低。本发明采用两个反应器，未反应的CH 2Cl 2和中间物HCFC-31进入第二反应器继续反应，使得CH 2Cl 2完全反应成HFC-32，提高了反应效率和反应能力，反应器空速500～3000h -1，较一般的气相反应流程，空速提高一倍多。本发明的方法可根据实际生产情况需要采用两个或多个反应器进行反应。 At present, the industrialized plant for gas phase synthesis of HFC-32 adopts a reactor, and the unreacted CH 2 Cl 2 and the intermediate product HCFC-31 are returned to the reactor, resulting in high reactor load and low production capacity. The present invention adopts two reactors, and the unreacted CH2Cl2 and the intermediate HCFC-31 enter the second reactor to continue the reaction, so that the CH2Cl2 is completely reacted into HFC-32, the reaction efficiency and the reaction ability are improved, and the reaction The space velocity of the reactor is 500～3000h -1 , which is more than doubled compared with the general gas phase reaction process. The method of the present invention may adopt two or more reactors for reaction according to actual production conditions.
传统的HFC-32生产工艺都是采用水洗、碱洗法除去如HF、HCl等少量的酸性物质，产生大量的废水，然后还要干燥。本发明采用的净化工艺，净化塔装填固体除酸剂和助剂，该工艺取代了传统的水洗、碱洗工艺，减少了废水，降低了能耗。The traditional production process of HFC-32 is to use water washing and alkali washing to remove a small amount of acidic substances such as HF and HCl, resulting in a large amount of waste water, and then drying. In the purification process adopted by the invention, the purification tower is filled with solid acid scavenger and auxiliary agent, which replaces the traditional water washing and alkaline washing processes, reduces waste water and reduces energy consumption.
现有技术的气相法工艺采用的催化剂都是铬基，辅助其它组分，大多采用共沉淀法制备，催化剂比表面积小，容易结碳失活。The catalysts used in the gas phase method in the prior art are all chromium-based, and other components are assisted, and most of them are prepared by a co-precipitation method. The catalyst has a small specific surface area and is easy to carbonize and deactivate.
本发明中制备纳米Cr 2O 3粉体时，将铬、辅助组分Ⅰ与辅助组分Ⅱ的化合物配制成混合溶液时，混合溶液中Cr 3+浓度的控制是关键。当Cr 3+浓度较高时，沉淀产物呈凝胶状，干燥后的产物常为坚硬的团聚体，煅烧后得到的是硬团聚的块状氧化铬，这种氧化铬比表面积很低；当Cr 3+浓度较低时，煅烧后可以得到疏松的氧化铬粉体，但Cr 3+浓度太低，影响催化剂性能。因此，本发明中配制成的混合溶液中Cr 3+的浓度为0.1～0.2mol/L。为了防止产生硬团聚现象，还要控制加料速度，本发明将配制得到的混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中进行反应时，碳酸氢铵溶液的液面面积上喷雾加料速度为10～25ml/min。传统的加料方式即便采用了比较慢的加料速度，但由于加料点两种液相接触的面积比较小，即使采用强力搅拌，也很难在短时间内把溶液混合均匀，难以避免的形成局部浓度不均匀，造成反应产物的硬团聚现象，最终导致了产物的不均匀，严重影响了产物的性能。另外，传统的加料方式由于加料速度慢，加料周期长，不可避免的导致了先加入的反应物和后加入的反应物反应环境差别很大，进一步导致了产物的不均匀。 When preparing nano Cr 2 O 3 powder in the present invention, when the compounds of chromium, auxiliary component I and auxiliary component II are prepared into mixed solution, the control of Cr 3+ concentration in the mixed solution is the key. When the concentration of Cr 3+ is high, the precipitation product is gel-like, and the product after drying is often a hard agglomerate. When the concentration of Cr 3+ is low, loose chromium oxide powder can be obtained after calcination, but the concentration of Cr 3+ is too low, which affects the performance of the catalyst. Therefore, the concentration of Cr 3+ in the mixed solution prepared in the present invention is 0.1-0.2 mol/L. In order to prevent the phenomenon of hard agglomeration, it is necessary to control the feeding speed. When the mixed solution prepared by the present invention is sprayed into the ammonium bicarbonate solution under stirring state for reaction by spraying and atomization, the liquid surface area of the ammonium bicarbonate solution is on the surface of the ammonium bicarbonate solution. The spray feed rate is 10-25ml/min. Even if the traditional feeding method adopts a relatively slow feeding speed, due to the relatively small contact area of the two liquid phases at the feeding point, even if strong stirring is used, it is difficult to mix the solution evenly in a short time, and it is difficult to avoid the formation of local concentration. Non-uniformity results in hard agglomeration of the reaction product, which eventually leads to the non-uniformity of the product, which seriously affects the performance of the product. In addition, due to the slow feeding speed and long feeding period of the traditional feeding method, the reaction environment of the reactant added first and the reactant added later is inevitably very different, which further leads to the unevenness of the product.
本发明中制备催化剂时将得到的超细氢氧化物经过干燥和煅烧得到氧化铬粉体。而传统的干燥方法一般使用烘箱进行干燥，能耗大，效率低，而且效果也不好，本发明采用二阶微波干燥，很好的控制了干燥过程中物料的均匀性。In the present invention, when the catalyst is prepared, the obtained ultrafine hydroxide is dried and calcined to obtain chromium oxide powder. The traditional drying method generally uses an oven for drying, which has high energy consumption, low efficiency, and poor effect.
与现有技术相比，本发明的优点为：Compared with the prior art, the advantages of the present invention are:
1、工艺简单，效率高，采用气相两步反应工艺，操作简单，反应条件温和，显著简化了生产流程，CH 2Cl 2的总转化率为100％。 1. The process is simple and the efficiency is high, the gas phase two -step reaction process is adopted, the operation is simple, the reaction conditions are mild, the production process is significantly simplified, and the total conversion rate of CH2Cl2 is 100%.
2、催化剂活性好，寿命长，本发明采用纳米技术制备催化剂时，通过控制混合溶液中Cr 3+的浓度和碳酸氢铵溶液的液面面积上喷雾加料速度，使得得到的产物均匀性好，提高了催化剂的比表面积，延缓了催化剂的结碳速度；采用二阶微波干燥，很好的控制了干燥过程中物料的均匀性，有效延长了催化剂的寿命。 2. The catalyst has good activity and long service life. When the catalyst is prepared by nanotechnology, the uniformity of the obtained product is good by controlling the concentration of Cr 3+ in the mixed solution and the spray feeding speed on the liquid surface area of the ammonium bicarbonate solution. The specific surface area of the catalyst is increased, and the carbonization rate of the catalyst is delayed; the second-order microwave drying is adopted, which can well control the uniformity of the material during the drying process, and effectively prolong the life of the catalyst.
3、安全环保，本发明采用装填固体除酸剂和助剂的净化塔除去HF、HCl等少量的酸性物质，该净化工艺比传统的水洗、碱洗工艺，显著减少了废水，降低了能耗。3. Safety and environmental protection, the present invention uses a purification tower filled with solid acid scavengers and auxiliary agents to remove a small amount of acidic substances such as HF and HCl. Compared with the traditional water washing and alkaline washing processes, the purification process significantly reduces waste water and energy consumption. .
附图说明Description of drawings
图1为本发明的工艺流程示意图。Fig. 1 is the process flow schematic diagram of the present invention.
如图所示：1为第一反应器，2为脱酸分离塔，3为第二反应器，4为氯化氢分离塔，5为净化塔，6为脱轻塔，7为干燥塔，8～18为流程管线As shown in the figure: 1 is the first reactor, 2 is the deacidification separation tower, 3 is the second reactor, 4 is the hydrogen chloride separation tower, 5 is the purification tower, 6 is the light-removing tower, 7 is the drying tower, 8～ 18 is the process pipeline
具体实施方式detailed description
如图1所示，本发明的气相催化合成二氟甲烷的方法，流程如下：As shown in Figure 1, the method for gas-phase catalytic synthesis of difluoromethane of the present invention, the flow process is as follows:
原料CH 2Cl 2和HF通过管线18进入装填有催化剂的第一反应器1，在催化剂作用下进行反应，反应后得到主要含有HFC-32、HCl、HCFC-31、HFC-23、未反应的CH 2Cl 2和HF的反应产物，将其通过管线8进入脱酸分离塔2进行分离，得到塔釜混合组分和塔顶产物；将脱酸分离塔2塔顶产物通过管线9进入氯化氢分离塔4，氯化氢分离塔4塔顶得到的氯化氢气体另行处理，氯化氢分离塔4塔釜得到的主要含HFC-32、少量HF和少量HFC-23的混合组分通过管线13进入装填有固体除酸剂和助剂的净化塔5进一步除掉少量氟化氢，净化塔5塔顶得到的主要含HFC-32和少量HFC-23的产物通过管线14进入脱轻塔6；通过脱轻塔6塔顶管线16得到少量HFC-23等轻组分，塔釜物料通过管线15进入干燥塔7进行干燥，从干燥塔7塔顶管线17得到HFC-32产品。脱酸分离塔2塔釜混合组分主要含HCFC-31、未反应的CH 2Cl 2和HF，将其通过管线10进入装填有催化剂的第二反应器3，在催化剂作用下进一步反应；第二反应器3出口主要含有HFC-32、HCl、HF和少量HCFC-31的反应产物通过管线11进入脱酸分离塔2。 The raw materials CH 2 Cl 2 and HF enter the first reactor 1 filled with the catalyst through the pipeline 18, and the reaction is carried out under the action of the catalyst. The reaction product of CH 2 Cl 2 and HF is separated into the deacidification separation tower 2 through the pipeline 8 to obtain the mixed components of the tower reactor and the overhead product; the overhead product of the deacidification separation column 2 enters the hydrogen chloride separation through the pipeline 9 Tower 4, the hydrogen chloride gas obtained at the top of the hydrogen chloride separation tower 4 is processed separately, and the mixed components that mainly contain HFC-32, a small amount of HF and a small amount of HFC-23 obtained from the 4 tower stills of the hydrogen chloride separation tower are filled with solid deacidification through pipeline 13. The purification tower 5 of agent and auxiliary agent further removes a small amount of hydrogen fluoride, and the product mainly containing HFC-32 and a small amount of HFC-23 obtained at the top of the purification tower 5 enters the light-removing tower 6 through pipeline 14; 16 to obtain a small amount of light components such as HFC-23, the material in the tower reactor enters the drying tower 7 through the line 15 for drying, and the HFC-32 product is obtained from the line 17 at the top of the drying tower 7. The mixed components of the tower reactor of the deacidification separation tower 2 mainly contain HCFC-31, unreacted CH 2 Cl 2 and HF, which are fed into the second reactor 3 filled with the catalyst through the pipeline 10, and further reacted under the action of the catalyst; The reaction product mainly containing HFC-32, HCl, HF and a small amount of HCFC-31 at the outlet of the second reactor 3 enters the deacidification separation tower 2 through the pipeline 11.
下面通过实施例对本发明作进一步说明，但本发明并不仅限于这些实施例。The present invention will be further illustrated by the following examples, but the present invention is not limited to these examples.
实施例1～7为催化剂的制备实施例Embodiments 1-7 are the preparation examples of catalysts
实施例1Example 1
催化剂的制备方法如下：The preparation method of the catalyst is as follows:
(a)按铬与钴的摩尔比为1:0.02，铬与锌的摩尔比为1:0.1，称取硝酸铬、辅助组分Ⅰ硝酸钴与辅助组分Ⅱ硝酸锌，配制成混合溶液，混合溶液中Cr 3+浓度为0.1mol/L； (a) According to the molar ratio of chromium and cobalt being 1:0.02 and the molar ratio of chromium and zinc being 1:0.1, weigh chromium nitrate, auxiliary component I cobalt nitrate and auxiliary component II zinc nitrate to prepare a mixed solution, The concentration of Cr 3+ in the mixed solution is 0.1mol/L;
(b)将上述混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中反应，并同时加入聚乙二醇，反应的温度为60℃，反应的时间为40min，碳酸氢铵溶液的液面面积上喷雾加料速度为15ml/min，碳酸氢铵溶液的初始浓度为1.0mol/L，聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.1％，控制反应终点pH值为8.0，得到反应液； (b) above-mentioned mixed solution is reacted in the ammonium bicarbonate solution under agitation after spraying atomization, and adds polyethylene glycol simultaneously, the temperature of reaction is 60 ℃, and the time of reaction is 40min, ammonium bicarbonate solution The spray feeding rate on the liquid surface area of 15ml/min is 15ml/min, the initial concentration of ammonium bicarbonate solution is 1.0mol/L, the addition amount of polyethylene glycol accounts for 0.1% of the total moles of Cr in the reaction solution, and the end point of the reaction is controlled. The pH value is 8.0 to obtain a reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行二阶微波干燥，二阶微波干燥的第一阶功率为200W，第二阶功率为200W，二阶微波干燥的总干燥时间为0.5h，干燥结束后在400℃下煅烧，得到纳米氧化铬粉体；(d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 200W, the second-order power is 200W, and the total drying time of the second-order microwave drying is 0.5 h, after drying, calcining at 400 °C to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得1#催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain 1# catalyst.
实施例2Example 2
催化剂的制备方法如下：The preparation method of the catalyst is as follows:
(a)按铬与镓的摩尔比为1:0.05，铬与铝的摩尔比为1:0.2，称取硝酸铬、辅助组分Ⅰ硝酸镓与辅助组分Ⅱ硝酸铝，配制成混合溶液，混合溶液中Cr 3+浓度为0.2mol/L； (a) According to the molar ratio of chromium to gallium of 1:0.05 and the molar ratio of chromium to aluminum to be 1:0.2, weigh chromium nitrate, auxiliary component I gallium nitrate and auxiliary component II aluminum nitrate to prepare a mixed solution, The concentration of Cr 3+ in the mixed solution is 0.2mol/L;
(b)将上述混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中反应，并同时加入聚乙二醇，反应的温度为50℃，反应的时间为100min，碳酸氢铵溶液的液面面积上喷雾加料速度为10ml/min，碳酸氢铵溶液的初始浓度为1.2mol/L，聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.3％，控制反应终点pH值为8.5，得到反应液； (b) above-mentioned mixed solution is reacted in the ammonium bicarbonate solution under agitation by spraying atomization, and adding polyethylene glycol simultaneously, the temperature of reaction is 50 ℃, and the time of reaction is 100min, ammonium bicarbonate solution The spray feeding speed on the liquid surface area of 10ml/min is 10ml/min, the initial concentration of ammonium bicarbonate solution is 1.2mol /L, the addition amount of polyethylene glycol accounts for 0.3% of the total moles of Cr in the reaction solution, and the end point of the reaction is controlled. The pH value is 8.5 to obtain a reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行二阶微波干燥，二阶微波干燥的第一阶功率为220W，第二阶功率为180W，二阶微波干燥的总干燥时间为1.0h，干燥结束后在600℃下煅烧，得到纳米氧化铬粉体；(d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 220W, the second-order power is 180W, and the total drying time of the second-order microwave drying is 1.0 h, after drying, calcining at 600 ° C to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得2#催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 2# catalyst.
实施例3Example 3
催化剂的制备方法如下：The preparation method of the catalyst is as follows:
(a)按铬与锌的摩尔比为1:0.1，铬与铝的摩尔比为1:0.3，称取硝酸铬、辅助组分Ⅰ硝酸锌与辅助组分Ⅱ硝酸铝，配制成混合溶液，混合溶液中Cr 3+浓度为0.15mol/L； (a) According to the molar ratio of chromium to zinc of 1:0.1 and the molar ratio of chromium to aluminum to be 1:0.3, weigh chromium nitrate, auxiliary component I zinc nitrate and auxiliary component II aluminum nitrate to prepare a mixed solution, The concentration of Cr 3+ in the mixed solution is 0.15mol/L;
(b)将上述混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中反应，并同时加入聚乙二醇，反应的温度为80℃，反应的时间为120min，碳酸氢铵溶液的液面面积上喷雾加料速度为20ml/min，碳酸氢铵溶液的初始浓度为1.5mol/L，聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.2％，控制反应终点pH值为9.0，得到反应液； (b) above-mentioned mixed solution is reacted in the ammonium bicarbonate solution under agitation after spraying atomization, and adds polyethylene glycol simultaneously, the temperature of reaction is 80 ℃, and the time of reaction is 120min, ammonium bicarbonate solution The spray feeding speed on the liquid surface area of 20ml/min is 20ml/min, the initial concentration of ammonium bicarbonate solution is 1.5mol /L, the addition amount of polyethylene glycol accounts for 0.2% of the total moles of Cr in the reaction solution, and the end point of the reaction is controlled. The pH value is 9.0 to obtain a reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行二阶微波干燥，二阶微波干燥的第一阶功率为240W，第二阶功率160W，二阶微波干燥的总干燥时间为0.7h，干燥结束后在700℃下煅烧，得到纳米氧化铬粉体；(d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 240W, the second-order power is 160W, and the total drying time of the second-order microwave drying is 0.7h , and calcined at 700 °C after drying to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得3#催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 3# catalyst.
实施例4Example 4
催化剂的制备方法如下：The preparation method of the catalyst is as follows:
(a)按铬与铁的摩尔比为1:0.07，铬与镓的摩尔比为1:0.5，称取硝酸铬、辅助组分Ⅰ硝酸铁与辅助组分Ⅱ硝酸镓，配制成混合溶液，混合溶液中Cr 3+浓度为0.15mol/L； (a) According to the molar ratio of chromium and iron being 1:0.07 and the molar ratio of chromium and gallium being 1:0.5, weigh chromium nitrate, auxiliary component I ferric nitrate and auxiliary component II gallium nitrate to prepare a mixed solution, The concentration of Cr 3+ in the mixed solution is 0.15mol/L;
(b)将上述混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中反应，并同时加入聚乙二醇，反应的温度为70℃，反应的时间为90min，碳酸氢铵溶液的液面面积上喷雾加料速度为25ml/min，碳酸氢铵溶液的初始浓度为1.3mol/L，聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.2％，控制反应终点pH值为8.0，得到反应液； (b) above-mentioned mixed solution is reacted in the ammonium bicarbonate solution under agitation after spraying atomization, and adds polyethylene glycol simultaneously, the temperature of reaction is 70 ℃, and the time of reaction is 90min, ammonium bicarbonate solution The spray feed rate on the liquid surface area is 25ml/min, the initial concentration of the ammonium bicarbonate solution is 1.3mol /L, the addition of polyethylene glycol accounts for 0.2% of the total moles of Cr in the reaction solution, and the end point of the reaction is controlled. The pH value is 8.0 to obtain a reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行二阶微波干燥，二阶微波干燥的第一阶功率为260W，第二阶功率为140W，二阶微波干燥的总干燥时间为0.6h，干燥结束后在600℃下煅烧，得到纳米氧化铬粉体；(d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 260W, the second-order power is 140W, and the total drying time of the second-order microwave drying is 0.6 h, after drying, calcining at 600 ° C to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得4#催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain 4# catalyst.
实施例5Example 5
催化剂的制备方法如下：The preparation method of the catalyst is as follows:
(a)按铬与锌的摩尔比为1:0.08，铬与铁的摩尔比为1:0.4，称取硝酸铬、辅助组分Ⅰ硝酸锌与辅助组分Ⅱ硝酸铁，配制成混合溶液，混合溶液中Cr 3+浓度为0.2mol/L； (a) According to the molar ratio of chromium and zinc to be 1:0.08 and the molar ratio of chromium to iron to be 1:0.4, weigh chromium nitrate, auxiliary component I zinc nitrate and auxiliary component II iron nitrate to prepare a mixed solution, The concentration of Cr 3+ in the mixed solution is 0.2mol/L;
(b)将上述混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中反应，并同时加入聚乙二醇，反应的温度为80℃，反应的时间为50min，碳酸氢铵溶液的液面面积上喷雾加料速度为20ml/min，碳酸氢铵溶液的初始浓度为1.4mol/L，聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.3％，控制反应终点pH值为8.5，得到反应液； (b) above-mentioned mixed solution is reacted in the ammonium bicarbonate solution under agitation after spraying atomization, and simultaneously adds polyethylene glycol, the temperature of reaction is 80 ℃, and the time of reaction is 50min, ammonium bicarbonate solution The spray feeding speed on the liquid surface area of 20ml/min is 20ml/min, the initial concentration of ammonium bicarbonate solution is 1.4mol /L, the addition amount of polyethylene glycol accounts for 0.3% of the total moles of Cr in the reaction solution, and the end point of the reaction is controlled. The pH value is 8.5 to obtain a reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行二阶微波干燥，二阶微波干燥的第一阶功率为280W，第二阶功率120W，二阶微波干燥的总干燥时间为0.8h，干燥结束后在500℃下煅烧，得到纳米氧化铬粉体；(d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 280W, the second-order power is 120W, and the total drying time of the second-order microwave drying is 0.8h , and calcined at 500 °C after drying to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得5#催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 5# catalyst.
实施例6Example 6
催化剂的制备方法如下：The preparation method of the catalyst is as follows:
(a)按铬与钴的摩尔比为1:0.04，铬与镍的摩尔比为1:0.5，称取硝酸铬、辅助组分Ⅰ硝酸钴与辅助组分Ⅱ硝酸镍，配制成混合溶液，混合溶液中Cr 3+浓度为0.1mol/L； (a) According to the molar ratio of chromium and cobalt being 1:0.04 and the molar ratio of chromium and nickel being 1:0.5, weigh chromium nitrate, auxiliary component I cobalt nitrate and auxiliary component II nickel nitrate to prepare a mixed solution, The concentration of Cr 3+ in the mixed solution is 0.1mol/L;
(b)将上述混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中反应，并同时加入聚乙二醇，反应的温度为70℃，反应的时间为80min，碳酸氢铵溶液的液面面积上喷雾加料速度为25ml/min，碳酸氢铵溶液的初始浓度为1.5mol/L，聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.2％，控制反应终点pH值为9.0，得到反应液； (b) above-mentioned mixed solution is reacted in the ammonium bicarbonate solution under agitation after being sprayed by spray atomization, and adds polyethylene glycol simultaneously, the temperature of reaction is 70 ℃, and the time of reaction is 80min, ammonium bicarbonate solution The spray feeding rate on the liquid surface area is 25ml/min, the initial concentration of the ammonium bicarbonate solution is 1.5mol /L, the addition amount of polyethylene glycol accounts for 0.2% of the total moles of Cr in the reaction solution, and the end point of the reaction is controlled. The pH value is 9.0 to obtain a reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行二阶微波干燥，二阶微波干燥的第一阶功率为300W，第二阶功率为100W，二阶微波干燥的总干燥时间为1h，干燥结束后在700℃下煅烧，得到纳米氧化铬粉体；(d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 300W, the second-order power is 100W, and the total drying time of the second-order microwave drying is 1h , and calcined at 700 °C after drying to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得6#催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 6# catalyst.
实施例7Example 7
催化剂的制备方法如下：The preparation method of the catalyst is as follows:
(a)按铬与镓的摩尔比为1:0.06，铬与锌的摩尔比为1:0.5，称取硝酸铬、辅助组分Ⅰ硝酸镓与辅助组分Ⅱ硝酸锌，配制成混合溶液，混合溶液中Cr 3+浓度为0.2mol/L； (a) According to the molar ratio of chromium and gallium being 1:0.06 and the molar ratio of chromium and zinc being 1:0.5, weigh chromium nitrate, auxiliary component I gallium nitrate and auxiliary component II zinc nitrate to prepare a mixed solution, The concentration of Cr 3+ in the mixed solution is 0.2mol/L;
(b)将上述混合溶液通过喷雾雾化后喷向搅拌状态下的碳酸氢铵溶液中反应，并同时加入聚乙二醇，反应的温度为80℃，反应的时间为120min，碳酸氢铵溶液的液面面积上喷雾加料速度为20ml/min，碳酸氢铵溶液的初始浓度为1.4mol/L，聚乙二醇的加 入量占反应溶液中Cr 3+总摩尔数的0.15％，控制反应终点pH值为8.0，得到反应液； (b) above-mentioned mixed solution is reacted in the ammonium bicarbonate solution under agitation after spraying atomization, and adds polyethylene glycol simultaneously, the temperature of reaction is 80 ℃, and the time of reaction is 120min, ammonium bicarbonate solution The spray feeding speed on the liquid surface area of 20ml/min is 20ml/min, the initial concentration of ammonium bicarbonate solution is 1.4mol /L, the addition amount of polyethylene glycol accounts for 0.15% of the total moles of Cr in the reaction solution, and the end point of the reaction is controlled. The pH value is 8.0 to obtain a reaction solution;
(c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
(d)将步骤(c)得到的超细氢氧化物进行二阶微波干燥，二阶微波干燥的第一阶功率为250W，第二阶功率为150W，二阶微波干燥的总干燥时间为0.9h，干燥结束后在600℃下煅烧，得到纳米氧化铬粉体；(d) performing second-order microwave drying on the ultrafine hydroxide obtained in step (c), the first-order power of the second-order microwave drying is 250W, the second-order power is 150W, and the total drying time of the second-order microwave drying is 0.9 h, after drying, calcining at 600 ° C to obtain nano-chromium oxide powder;
(e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得7#催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a 7# catalyst.
实施例8～15为二氟甲烷的制备实施例Embodiments 8-15 are the preparation examples of difluoromethane
实施例8Example 8
第一反应器装填1#催化剂，第二反应器装填2#，净化塔中装填有固体除酸剂NaOH和助剂磷酸三钠，固体除酸剂NaOH与助剂磷酸三钠的质量比为2:1，反应条件及两个反应器出口有机物组成见表1。The first reactor is filled with 1# catalyst, the second reactor is filled with 2#, and the purification tower is filled with solid acid scavenger NaOH and auxiliary trisodium phosphate, and the mass ratio of solid acid scavenger NaOH and auxiliary trisodium phosphate is 2 : 1, the reaction conditions and the composition of the organic matter at the outlet of the two reactors are shown in Table 1.
表1实施例8第一反应器和第二反应器反应条件及出口有机物组成Table 1 Example 8 The first reactor and the second reactor reaction conditions and the composition of the organic matter at the outlet
Figure PCTCN2021106982-appb-000001
Figure PCTCN2021106982-appb-000001
实施例9Example 9
第一反应器装填1#催化剂，第二反应器装填2#，净化塔中装填有固体除酸剂NaOH和助剂磷酸三钠，固体除酸剂NaOH与助剂磷酸三钠的质量比为2:1，反应条件及两个反应器出口有机物组成见表2。The first reactor is filled with 1# catalyst, the second reactor is filled with 2#, and the purification tower is filled with solid acid scavenger NaOH and auxiliary trisodium phosphate, and the mass ratio of solid acid scavenger NaOH and auxiliary trisodium phosphate is 2 : 1, the reaction conditions and the composition of the organic matter at the outlet of the two reactors are shown in Table 2.
表2实施例9第一反应器和第二反应器反应条件及出口有机物组成Table 2 Example 9 The first reactor and the second reactor reaction conditions and the composition of the outlet organic matter
Figure PCTCN2021106982-appb-000002
Figure PCTCN2021106982-appb-000002
Figure PCTCN2021106982-appb-000003
Figure PCTCN2021106982-appb-000003
实施例10Example 10
第一反应器装填2#催化剂，第二反应器装填5#，净化塔中装填有固体除酸剂Ca(OH) 2和助剂磷酸钙，固体除酸剂Ca(OH) 2与助剂磷酸钙的质量比为3:1。反应条件及两个反应器出口有机物组成见表4。 The first reactor is filled with 2# catalyst, the second reactor is filled with 5#, and the purification tower is filled with solid acid scavenger Ca(OH) 2 and auxiliary calcium phosphate, solid acid scavenger Ca(OH) 2 and auxiliary phosphoric acid The mass ratio of calcium is 3:1. The reaction conditions and the composition of the organic matter at the outlet of the two reactors are shown in Table 4.
表3实施例10第一反应器和第二反应器反应条件及出口有机物组成Table 3 embodiment 10 first reactor and second reactor reaction conditions and outlet organic composition
Figure PCTCN2021106982-appb-000004
Figure PCTCN2021106982-appb-000004
实施例11Example 11
第一反应器装填2#催化剂，第二反应器装填5#，净化塔中装填有固体除酸剂Ca(OH) 2和助剂磷酸钙，固体除酸剂Ca(OH) 2与助剂磷酸钙的质量比为3:1。反应条件及两个反应器出口有机物组成见表4。 The first reactor is filled with 2# catalyst, the second reactor is filled with 5#, and the purification tower is filled with solid acid scavenger Ca(OH) 2 and auxiliary calcium phosphate, solid acid scavenger Ca(OH) 2 and auxiliary phosphoric acid The mass ratio of calcium is 3:1. The reaction conditions and the composition of the organic matter at the outlet of the two reactors are shown in Table 4.
表4实施例11第一反应器和第二反应器反应条件及出口有机物组成Table 4 Example 11 The first reactor and the second reactor reaction conditions and the composition of the outlet organic matter
Figure PCTCN2021106982-appb-000005
Figure PCTCN2021106982-appb-000005
实施例12Example 12
第一反应器装填3#催化剂，第二反应器装填4#，净化塔中装填有固体除酸剂和助剂所述的固体除酸剂Ba(OH) 2和助剂碳酸钙，固体除酸剂Ba(OH) 2与助剂碳酸钙的质量比为4:1，反应条件及两个反应器出口有机物组成见表5。 The first reactor is filled with 3# catalyst, the second reactor is filled with 4#, and the purification tower is filled with the solid acid scavenger Ba(OH) 2 and the auxiliary calcium carbonate described in the solid acid scavenger and auxiliary agent, and the solid acid scavenger is The mass ratio of the agent Ba(OH) 2 and the auxiliary agent calcium carbonate is 4:1, and the reaction conditions and the organic matter composition of the two reactor outlets are shown in Table 5.
表5实施例12第一反应器和第二反应器反应条件及出口有机物组成Table 5 Example 12 The first reactor and the second reactor reaction conditions and the composition of the organic matter at the outlet
Figure PCTCN2021106982-appb-000006
Figure PCTCN2021106982-appb-000006
实施例13Example 13
第一反应器装填3#催化剂，第二反应器装填4#，净化塔中装填有固体除酸剂和助剂所述的固体除酸剂Ba(OH) 2和助剂碳酸钙，固体除酸剂Ba(OH) 2与助剂碳酸钙的质量比为4:1，反应条件及两个反应器出口有机物组成见表5。 The first reactor is filled with 3# catalyst, the second reactor is filled with 4#, and the purification tower is filled with the solid acid scavenger Ba(OH) 2 and the auxiliary calcium carbonate described in the solid acid scavenger and auxiliary agent, and the solid acid scavenger is The mass ratio of the agent Ba(OH) 2 and the auxiliary agent calcium carbonate is 4:1, and the reaction conditions and the organic matter composition of the two reactor outlets are shown in Table 5.
表6实施例13第一反应器和第二反应器反应条件及出口有机物组成Table 6 Example 13 The first reactor and the second reactor reaction conditions and the composition of the organic matter at the outlet
Figure PCTCN2021106982-appb-000007
Figure PCTCN2021106982-appb-000007
实施例14Example 14
第一反应器装填6#催化剂，第二反应器装填7#，净化塔中装填有质量比为1:1的固体除酸剂Al(OH) 3和Fe(OH) 3，质量比为1:1的助剂亚硫酸氢钙和亚硫酸钠，除酸剂与 助剂的质量比为1:1。反应条件及两个反应器出口有机物组成见表6。 The first reactor is filled with 6# catalyst, the second reactor is filled with 7#, and the purification tower is filled with solid acid scavengers Al(OH) 3 and Fe(OH) 3 with a mass ratio of 1:1, and the mass ratio is 1: The auxiliaries of 1 are calcium bisulfite and sodium sulfite, and the mass ratio of acid scavenger and auxiliary is 1:1. The reaction conditions and the composition of the organic matter at the outlet of the two reactors are shown in Table 6.
表7实施例14第一反应器和第二反应器反应条件及出口有机物组成Table 7 Example 14 The first reactor and the second reactor reaction conditions and the composition of the outlet organic matter
Figure PCTCN2021106982-appb-000008
Figure PCTCN2021106982-appb-000008
实施例15Example 15
第一反应器装填3#催化剂，第二反应器装填4#，净化塔中装填有固体除酸剂和助剂所述的固体除酸剂Ba(OH) 2和助剂碳酸钙，固体除酸剂Ba(OH) 2与助剂碳酸钙的质量比为4:1，反应条件及两个反应器出口有机物组成见表5。 The first reactor is filled with 3# catalyst, the second reactor is filled with 4#, and the purification tower is filled with the solid acid scavenger Ba(OH) 2 and the auxiliary calcium carbonate described in the solid acid scavenger and auxiliary agent, and the solid acid scavenger is The mass ratio of the agent Ba(OH) 2 and the auxiliary agent calcium carbonate is 4:1, and the reaction conditions and the organic matter composition of the two reactor outlets are shown in Table 5.
表8实施例15第一反应器和第二反应器反应条件及出口有机物组成Table 8 Example 15 The reaction conditions of the first reactor and the second reactor and the composition of the organic matter at the outlet
Figure PCTCN2021106982-appb-000009
Figure PCTCN2021106982-appb-000009

Claims (10)

  1. 一种气相催化合成二氟甲烷的方法，其特征在于，包括以下步骤：A method for gas-phase catalytic synthesis of difluoromethane, characterized in that, comprising the following steps:
    (a)在催化剂作用下，将二氯甲烷和氟化氢进入第一反应器进行催化反应，得到第一反应产物；(a) under the action of a catalyst, dichloromethane and hydrogen fluoride are entered into the first reactor to carry out catalytic reaction to obtain the first reaction product;
    (b)将步骤(a)得到的第一反应产物进入脱酸分离塔，得到塔釜组分和塔顶组分；(b) the first reaction product obtained in step (a) is entered into the deacidification separation tower to obtain the tower still component and the tower top component;
    (c)将步骤(b)得到的塔顶组分分离氯化氢后得到含二氟甲烷的混合物料；(c) obtain the mixture material containing difluoromethane after the tower top component obtained in step (b) is separated from hydrogen chloride;
    (d)将步骤(c)得到的混合物料进入净化塔，得到净化后的混合物；(d) the mixture material that step (c) obtains enters purification tower, obtains the mixture after purification;
    (e)将步骤(d)得到的净化后的混合物进入脱轻塔，塔顶得到轻组分，塔釜物料经干燥，得到二氟甲烷产品。(e) entering the purified mixture obtained in step (d) into a light-removing tower, obtaining light components at the top of the tower, and drying the material in the tower to obtain a difluoromethane product.
  2. 根据权利要求1所述的气相催化合成二氟甲烷的方法，其特征在于，将步骤(b)得到的塔釜组分进入第二反应器，使用步骤(a)相同的催化剂进行催化反应，所述催化反应的温度为250～350℃，得到第二反应产物，将所述的第二反应产物进入所述的脱酸分离塔。The method for synthesizing difluoromethane by gas-phase catalysis according to claim 1, is characterized in that, the tower reactor component obtained in step (b) is entered into the second reactor, and the same catalyst in step (a) is used to carry out catalytic reaction, so that The temperature of the catalytic reaction is 250-350° C. to obtain a second reaction product, and the second reaction product is fed into the deacidification separation tower.
  3. 根据权利要求1所述的气相催化合成二氟甲烷的方法，其特征在于，步骤(a)所述的催化反应的温度为200～400℃，空速为500～3000h -1，氟化氢和二氯甲烷的摩尔比为10～20:1。 The method for synthesizing difluoromethane by gas phase catalysis according to claim 1, wherein the temperature of the catalytic reaction in step (a) is 200-400°C, the space velocity is 500-3000h -1 , the hydrogen fluoride and dichloromethane are The molar ratio of methane is 10-20:1.
  4. 根据权利要求1所述的气相催化合成二氟甲烷的方法，其特征在于，所述催化剂以铬为主要组分，选自钴、锌、铁、镓中的一种为辅助组分Ⅰ，选自铝、锌、铁、镍、镓中的一种为辅助组分Ⅱ，且辅助组分Ⅰ与辅助组分Ⅱ不同，铬与辅助组分Ⅰ的摩尔比为1:0.02～0.1，铬与辅助组分Ⅱ的摩尔比为1:0.1～0.5。The method for synthesizing difluoromethane by gas-phase catalysis according to claim 1, wherein the catalyst takes chromium as the main component, and one selected from cobalt, zinc, iron, and gallium is the auxiliary component I. Since one of aluminum, zinc, iron, nickel, and gallium is auxiliary component II, and auxiliary component I is different from auxiliary component II, the molar ratio of chromium and auxiliary component I is 1:0.02~0.1, and chromium and auxiliary component I The molar ratio of auxiliary component II is 1:0.1-0.5.
  5. 根据权利要求4所述的气相催化合成二氟甲烷的方法，其特征在于，所述催化剂是按以下方法制备得到的：The method for gas-phase catalytic synthesis of difluoromethane according to claim 4, wherein the catalyst is prepared by the following method:
    (a)按比例称取铬、辅助组分Ⅰ与辅助组分Ⅱ的化合物，配制成混合溶液；(a) weigh the compounds of chromium, auxiliary component I and auxiliary component II in proportion to prepare a mixed solution;
    (b)将上述混合溶液通过喷雾雾化后喷向碳酸氢铵溶液中反应，并同时加入表面活性剂，控制反应终点pH值为8.0～9.0，得到反应液；(b) above-mentioned mixed solution is sprayed in ammonium bicarbonate solution by spray atomization to react, and simultaneously adds surfactant, and controls the pH value of reaction end point to be 8.0～9.0, obtains reaction solution;
    (c)将步骤(b)得到的反应液经老化、过滤、洗涤，得到超细氢氧化物；(c) the reaction solution obtained in step (b) is subjected to aging, filtration and washing to obtain ultrafine hydroxide;
    (d)将步骤(c)得到的超细氢氧化物进行微波干燥，煅烧，得到纳米氧化铬粉体；(d) microwave drying and calcining the ultrafine hydroxide obtained in step (c) to obtain nano-chromium oxide powder;
    (e)将步骤(d)得到的纳米氧化铬粉体压片成型，氟化后制得催化剂。(e) compressing the nano-chromium oxide powder obtained in step (d) into a tablet, and fluorinating to obtain a catalyst.
  6. 根据权利要求5所述的气相催化合成二氟甲烷的方法，其特征在于，步骤(a)中所述的铬、辅助组分Ⅰ与辅助组分Ⅱ的化合物为硝酸盐或氯化物，所述的混合溶液中Cr 3+的浓度为0.1～0.2mol/L。 The method for synthesizing difluoromethane by gas-phase catalysis according to claim 5, wherein the compounds of chromium, auxiliary component I and auxiliary component II described in step (a) are nitrates or chlorides, and the The concentration of Cr 3+ in the mixed solution is 0.1～0.2mol/L.
  7. 根据权利要求5所述的气相催化合成二氟甲烷的方法，其特征在于，步骤(b)中所述的反应的温度为50～80℃，反应的时间为30～120min，所述的碳酸氢铵溶液的液面面积上喷雾加料速度为10～25ml/min，所述的碳酸氢铵溶液的初始浓度为1.0～1.5mol/L。The method for synthesizing difluoromethane by gas-phase catalysis according to claim 5, wherein the temperature of the reaction described in the step (b) is 50-80° C., the time of the reaction is 30-120 min, and the hydrogen carbonate The spray feed rate on the liquid surface area of the ammonium solution is 10-25 ml/min, and the initial concentration of the ammonium bicarbonate solution is 1.0-1.5 mol/L.
  8. 根据权利要求5所述的气相催化合成二氟甲烷的方法，其特征在于，步骤(b)中所述的表面活性剂为聚乙二醇，所述聚乙二醇的加入量占反应溶液中Cr 3+总摩尔数的0.1～0.3％。 The method for synthesizing difluoromethane by gas-phase catalysis according to claim 5, wherein the surfactant described in the step (b) is polyethylene glycol, and the amount of the polyethylene glycol added accounts for 5% of the reaction solution. 0.1-0.3% of the total moles of Cr 3+ .
  9. 根据权利要求5所述的气相催化合成二氟甲烷的方法，其特征在于，步骤(d)中所述的微波干燥为二阶微波干燥，所述二阶微波干燥的第一阶功率为200～300W，第二阶功率为100～200W，所述二阶微波干燥的总干燥时间为0.5～1h，所述的煅烧的温度400～700℃。The method for synthesizing difluoromethane by gas-phase catalysis according to claim 5, wherein the microwave drying in step (d) is second-order microwave drying, and the first-order power of the second-order microwave drying is 200~ 300W, the second-stage power is 100-200W, the total drying time of the second-stage microwave drying is 0.5-1h, and the calcination temperature is 400-700°C.
  10. 根据权利要求1所述的气相催化合成二氟甲烷的方法，其特征在于，所述的净化塔中装填有固体除酸剂和助剂，所述的固体除酸剂和助剂的质量比为1～4:1，所述的固体除酸剂为KOH、Mg(OH) 2、NaOH、Ca(OH) 2、Al(OH) 3、Ba(OH) 2、Zn(OH) 2、Fe(OH) 3中的至少一种，所述的助剂为磷酸、磷酸三钠、磷酸钙、亚硫酸氢钙、碳酸钙、亚硫酸钠中的至少一种。 The method for gas-phase catalytic synthesis of difluoromethane according to claim 1, wherein the purification tower is filled with a solid acid scavenger and an auxiliary, and the mass ratio of the solid acid scavenger and the auxiliary is 1～4:1, the solid acid scavenger is KOH, Mg(OH) 2 , NaOH, Ca(OH) 2 , Al(OH) 3 , Ba(OH) 2 , Zn(OH) 2 , Fe( OH) 3 , the auxiliary agent is at least one of phosphoric acid, trisodium phosphate, calcium phosphate, calcium hydrogen sulfite, calcium carbonate, and sodium sulfite.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4147733A (en) * 1978-05-22 1979-04-03 The Dow Chemical Company Fluorination of chlorinated hydrocarbons
CN102895967A (en) * 2012-09-29 2013-01-30 浙江衢化氟化学有限公司 Catalyst for producing HFC-32 vapor phase method and preparation method thereof
CN103319303A (en) * 2013-05-23 2013-09-25 浙江衢化氟化学有限公司 Method for simultaneously preparing 1,1,1,2-tetrafluoroethane and difluoromethane
CN110818526A (en) * 2019-11-27 2020-02-21 福建省清流县东莹化工有限公司 Process for preparing difluoromethane by gas phase method
CN112047803A (en) * 2020-08-06 2020-12-08 浙江衢化氟化学有限公司 Method for synthesizing difluoromethane by gas phase catalysis

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4147733A (en) * 1978-05-22 1979-04-03 The Dow Chemical Company Fluorination of chlorinated hydrocarbons
CN102895967A (en) * 2012-09-29 2013-01-30 浙江衢化氟化学有限公司 Catalyst for producing HFC-32 vapor phase method and preparation method thereof
CN103319303A (en) * 2013-05-23 2013-09-25 浙江衢化氟化学有限公司 Method for simultaneously preparing 1,1,1,2-tetrafluoroethane and difluoromethane
CN110818526A (en) * 2019-11-27 2020-02-21 福建省清流县东莹化工有限公司 Process for preparing difluoromethane by gas phase method
CN112047803A (en) * 2020-08-06 2020-12-08 浙江衢化氟化学有限公司 Method for synthesizing difluoromethane by gas phase catalysis

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