JP5057954B2 - Method for producing hydrocarbon oil - Google Patents

Description

The present invention relates to a method for producing a hydrocarbon oil from a raw material oil containing an oil and fat component derived from animals and plants.

Attention has been focused on the effective use of biomass energy as a measure to prevent global warming. Among them, biomass energy derived from plants can effectively use carbon immobilized from carbon dioxide in the atmosphere by photosynthesis during the growth process of plants, so it does not lead to an increase in carbon dioxide in the atmosphere from the viewpoint of the life cycle, so-called It has the property of being carbon neutral.

Various uses of such biomass energy have been studied in the field of transportation fuel. For example, if a fuel derived from animal and vegetable oils can be used as a diesel fuel, it is expected to play an effective role in reducing carbon dioxide emissions due to a synergistic effect with the high energy efficiency of a diesel engine. As diesel fuel using animal and vegetable oils, fatty acid methyl ester oil is generally used (Fatty Acid Methyl Ester).
Is abbreviated as “FAME”. )It has been known. FAME is produced by subjecting triglyceride, which is a general structure of animal and vegetable oils, to transesterification with methanol by the action of an alkali catalyst or the like.

However, in the process for producing FAME, as described in Patent Document 1 below, it is necessary to treat glycerin produced as a by-product, and problems such as cost and energy are required for cleaning the produced oil. ing.

Also, FAME has two oxygen atoms in one molecule, so it has an extremely high oxygen content as a fuel. Even when blended with conventional diesel fuel derived from petroleum, this oxygen content is still in the engine. There is also a problem that adverse effects on materials are concerned.

Therefore, a method for producing a fuel oil composed of hydrocarbons substantially free of oxygen by hydrodeoxygenating raw material oils containing animal and plant-derived fats and oils in the presence of a hydrogenation catalyst has been studied ( For example, see the following Patent Document 2.)

On the other hand, oil and fat components derived from animals and plants inherently contain an alkali metal component, an alkaline earth metal component, and a transition metal component as trace impurity elements. These metal components poison the active sites on the hydrogenation catalyst used in the hydrodeoxygenation treatment step and reduce the hydrodeoxygenation activity. In addition, the deposition of these metal components on the catalyst may block the catalyst layer and generate a differential pressure, which may make it difficult to operate the reactor. Further, in some cases, drift of the feedstock is induced in the reactor, and there is a risk of causing disorder of control of the reaction due to local heat generation.

In order to solve the above problems, as a pretreatment of the hydrodeoxygenation treatment process, a method for removing these metals contained in oil components derived from plants has been proposed (for example, Patent Document 3 below). See).
JP 2005-154647 A JP 2003-171670 A US 2006/264684 A1

However, according to the study by the present inventors, in the method described in Patent Document 3, the removal of the metal contained in the raw material oil is insufficient, and the raw material subjected to the pretreatment by the method When the oil is subjected to a hydrodeoxygenation step, the activity of the hydrogenation catalyst is reduced, and the increase in the oxygen content in the product oil and the decrease in oxidation stability associated with the increase in the carbon-carbon double bond content result in a decrease in fuel. There remains a problem with the undesirable quality of oil.

The present invention has been made in view of the above circumstances, and in producing a hydrocarbon oil by hydrodeoxygenating a raw oil containing an oil and fat component derived from animals and plants, the oxygen content is sufficiently reduced, And a method for producing a hydrocarbon oil capable of efficiently and stably obtaining a hydrocarbon oil having practical oxidation stability as a fuel oil, and a diesel oil for a diesel engine obtained by the production method. Objective.

The present inventors washed raw material oil containing an oil and fat component derived from animals and plants so that the content of alkali metal, alkaline earth metal, and transition metal contained in the oil is less than a specific value. By doing so, the activity reduction of the hydrogenation catalyst used in the hydrodeoxygenation process of the raw material oil is suppressed, the oxygen content is sufficiently reduced, and carbonization having practical oxidation stability as a fuel oil. The inventors have found that hydrogen oil can be obtained efficiently and stably, and have completed the present invention.

That is, the present invention is obtained by contacting and mixing a raw oil containing an oil and fat component derived from animals and plants and an acid aqueous solution, and the total content of alkali metal, alkaline earth metal and transition metal in the raw oil is 15 mass ppm. A cleaning step for cleaning the raw material oil, and a hydrodeoxygenation step for bringing the raw material oil cleaned by the cleaning step and the hydrogenation catalyst into contact with each other under hydrogen pressure to produce a hydrocarbon oil, as follows: And a temperature at which the raw material oil and the aqueous acid solution are mixed in contact in the washing step is 40 to 100 ° C.

The acid aqueous solution used in the washing step is phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, acetic acid, citric acid,
It is preferable to include at least one selected from the group consisting of tartaric acid.

Further, in the washing step, the temperature at the time of mixing and contacting the feedstock with an aqueous acid solution is Ru 40 to 100 ° C. der.

Moreover, it is preferable that a washing | cleaning process includes the contact mixing process which carries out contact mixing of raw material oil and acid aqueous solution, and the centrifugation process which centrifuges about the mixture obtained at a contact mixing process.

Moreover, it is preferable that the usage-amount of the acid aqueous solution in a washing | cleaning process is 0.01-20 mass% with respect to raw material oil.

The hydrogenation catalyst used in the hydrodeoxygenation step is a porous inorganic oxide comprising two or more elements selected from the group consisting of aluminum, silicon, zirconium, boron, titanium, and magnesium, and It is preferable to contain one or more metal elements belonging to Groups 6, 9, and 10 of the periodic table of the elements supported on the porous inorganic oxide.

Further, the porous inorganic oxide constituting the hydrogenation catalyst preferably further contains phosphorus as a constituent element.

Further, iodine value of the hydrocarbon oil obtained by hydrodeoxygenation step _0.1g-I 2/10
It is preferably 0 g or less.

Further, the increase in the acid value after oxygen gas was blown into the hydrocarbon oil obtained in the hydrodeoxygenation step at 115 ° C. for 16 hours was 0.25 mg-KOH based on the acid value before blowing oxygen gas.
/ G or less is preferable.

Moreover, this invention provides the diesel oil characterized by including the hydrocarbon oil obtained by the manufacturing method of the hydrocarbon oil of the said invention.

According to the present invention, when producing a hydrocarbon oil by hydrodeoxygenating a raw oil containing an oil and fat component derived from animals and plants, the oxygen content is sufficiently reduced, and practical oxidation as a fuel oil is achieved. It is possible to efficiently and stably obtain a hydrocarbon oil having stability, and a diesel oil for diesel engines based on the hydrocarbon oil having the above properties is provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

(Raw oil)
The oil and fat component derived from animals and plants used as a raw material in the present invention is artificially produced using natural or natural products as raw materials, animal and vegetable oils and fats produced and produced from these fats and oils,
This refers to the component that is produced. Animal fats and raw materials for animal oil include beef tallow and milk lipid (butter)
, Pork fat, sheep fat, whale oil, fish oil, liver oil, etc., as vegetable oil and vegetable oil raw materials, coconut palm, palm palm, olive, safflower, rapeseed (rapeseed), rice bran, sunflower, cottonseed, corn, Examples include seeds such as soybeans, sesame seeds, and flaxseed, and other parts. However, there is no problem in using oils and oils other than these. It does not matter whether these feedstock oils are solid or liquid at room temperature. Moreover, it is preferable to use vegetable oils and fats and vegetable oils as raw materials from the viewpoints of easy handling, reduction of carbon dioxide emissions, and high productivity. Also,
In the present invention, waste oils using these animal oils and vegetable oils for consumer use, industrial use, food use, etc. can also be used as raw materials after a removal step of impurities and the like.

As a typical composition of the fatty acid portion of the glyceride compound contained in these raw materials,
Butyric acid (C ₃ H ₇ CO, which is a fatty acid having no unsaturated bond in the molecular structure called saturated fatty acid)
OH), caproic acid (C ₅ H ₁₁ COOH), caprylic acid (C ₇ H ₁₅ COOH), capric acid (C ₉ H ₁₉ COOH), lauric acid (C ₁₁ H ₂₃ COOH), myristic acid (
C ₁₃ H ₂₇ COOH), palmitic acid (C ₁₅ H ₃₁ COOH), stearic acid (C _1
7 H ₃₅ COOH), and oleic acid (C ₁₇ H ₃₃ COOH), linoleic acid (C ₁₇ H ₃₁ COOH), linolenic acid (unsaturated fatty acids having one or more unsaturated bonds)
C ₁₇ H ₂₉ COOH), ricinolenic acid (C ₁₇ H ₃₂ (OH) COOH) and the like. In general, the hydrocarbon portion of these fatty acids produced in nature is often linear, but in the present invention, even if it has a structure having a side chain, as long as the properties defined in the present invention are satisfied. Can do. Further, in the present invention, the position of the unsaturated bond in the molecule of the unsaturated fatty acid is not limited to those generally confirmed in nature as long as the properties defined in the present invention are satisfied, and may be arbitrarily determined by a chemical method. The one set at the position can also be used.

The above-mentioned raw material oils (animal and vegetable oils and fats and components derived from animal and vegetable oils and fats) have one or more of these fatty acid components, and the fatty acids they have differ depending on the raw materials. For example, coconut oil has a relatively large amount of saturated fatty acids such as lauric acid and myristic acid, while soybean oil has a large amount of unsaturated fatty acids such as oleic acid and linoleic acid.

(Washing process)
The washing step in the production method of the present invention is a method in which the raw material oil and the acid aqueous solution are contact-mixed, and the total content of alkali metal, alkaline earth metal and transition metal in the raw material oil is 15 mass pp.
This is a step of washing the raw material oil so as to be m or less. In this step, the feedstock oil and the aqueous acid solution are contact-mixed to produce water from the feedstock oil in which the alkali metal component, the alkaline earth metal component and the transition metal component that are mainly contained in the feedstock oil are in the oil phase. By extracting to the phase side, at least some of them are removed from the feedstock.

The acid component constituting the acid aqueous solution to be mixed with the raw material oil is not particularly limited as long as it dissolves in water at the washing treatment temperature. For example, inorganic acids such as phosphoric acid, sulfuric acid, hydrochloric acid, nitric acid, citric acid, Organic acids such as acetic acid, oxalic acid, and tartaric acid are preferable.
Among these, phosphoric acid, sulfuric acid, and citric acid are more preferable because of high removal efficiency of impurities mainly composed of alkali metal, alkaline earth metal, and transition metal, and phosphoric acid and sulfuric acid are more preferable. Further, sulfuric acid is particularly preferable from the viewpoint of regulation of phosphorus concentration in waste water.

The temperature at which the raw material oil and the aqueous acid solution are subjected to contact mixing is 40 to 100 ° C., more preferably 40 to
90 ° C., particularly preferably 45 to 85 ° C. When the temperature is lower than the lower limit temperature, the metal removal efficiency is low, and when the upper limit temperature is exceeded, there is a risk of causing insolubles due to side reactions due to contact with the acid aqueous solution. In addition, it is not preferable in terms of requiring pressure resistant equipment.

The amount of the acid aqueous solution added to the raw material oil is 0.01 to 20% by mass based on the mass of the raw material oil.
Is preferable, 0.1-10 mass% is more preferable, 0.1-5 mass% is especially preferable. When the addition amount of the acid aqueous solution is less than the lower limit value, the metal removal efficiency is low, and when the upper limit value is exceeded, the acid itself may remain in the cleaning treatment oil and become an impurity. In addition, there is a tendency that the amount of spent acid aqueous solution increases and the burden of wastewater treatment and the like increases.

The acid concentration in the aqueous acid solution is preferably 0.001 to 5 mass%, more preferably 0.005 to 3 mass%, based on the mass of the aqueous acid solution. When the acid component concentration is less than 0.001% by mass, the metal removal efficiency is low. On the other hand, when it exceeds 5% by mass, the acid component itself may remain in the cleaning oil and become an impurity. It is not preferable.

The method for adding the aqueous acid solution in the contact mixing step of the raw material oil and the aqueous acid solution among the washing steps is not particularly limited, but is injected as a parallel flow with respect to the flow of the raw material oil, and a stationary mixing device such as a static mixer. From the viewpoint of processing efficiency, it is preferable to continuously mix them using the above. As other methods, it is also possible to employ a batch system in which a mixing and stirring tank is provided and mixed while stirring with a stirrer or the like, or a semi-batch system in which the mixture is continuously replaced.

In the washing step, the mixture obtained by the contact mixing step is composed of an oil phase and an aqueous phase containing a metal component and an acid, and it is necessary to separate the oil phase from the aqueous phase and recover the oil phase. .
For this purpose, there is also a method of separating the oil phase / water phase after allowing the mixture to stand and separate in a stationary tank, but from the viewpoint of treatment efficiency and removal efficiency of metal and acid from the oil phase, It is preferred to separate these two phases by centrifugation.

Among the washing steps, separation conditions in the centrifugation step can be arbitrarily set so as to satisfy a predetermined separation efficiency. Among these, the centrifugal effect of the centrifugal separator is preferably 500 G or more, more preferably 800 G or more, and particularly preferably 1000 G or more. When the centrifugal effect is less than 500 G, the separation efficiency of the acid aqueous solution decreases, and the impurity removal efficiency tends to decrease.

Since the aqueous solution after extraction can be efficiently separated from the oil phase, it is preferable to perform the separation with a centrifugal separator because the separation and removal efficiency of impurities including transition metal or phosphorus tends to be improved. The centrifugal separation is preferably a continuous type from the viewpoint of processing efficiency. The centrifugal separation method is not particularly limited, but any one of a general rotating cylinder type, a separation plate type, and a decanter type can be adopted.

The oil phase separated and recovered in the above separation step may be further mixed with water and washed with water, and then the oil phase and the aqueous phase may be separated again to recover the oil phase. This is performed in order to remove the component derived from the acid used for washing in the oil phase and further reduce the residual impurity concentration.

In addition, quantification of the metal content contained in the raw material oil and the raw material oil after the washing treatment here is IP
-501 “Determination of aluminum, Silicon,
vanadium, nickel, iron, sodium, calcium, z
inc and phosphorous in residual fuel oil
by asking, fusion and inductive couple
It is performed in accordance with the method described in “d plasma emission spectroscopy”. In other words, sulfur is added to the sample as a metal scavenger and ashed by combustion. After adding hydrochloric acid to the ash and dissolving it, water is added and dissolved, and then the metal concentration is determined by ICP (inductively coupled plasma) emission spectroscopy. Measure.

The total content of alkali metal, alkaline earth metal and transition metal contained in the raw oil washed by the washing step is preferably 15 ppm by mass or less based on the mass of the treated oil. It is more preferable that it is 10 mass ppm or less. If the total metal content exceeds 15 ppm by mass, the hydrodeoxygenation step and the hydrodeoxygenation activity of olefins derived from unsaturated fatty acid components contained in the feedstock are reduced in the hydrodeoxygenation step. ,
This is not preferable because the oxygen content of the product oil increases and the oxidation stability of the product oil tends to decrease.

  (Hydro-deoxygenation process)

In the present invention, “hydrodeoxygenation” means that oxygen atoms constituting the oxygen-containing organic compound are removed,
It means a process of adding hydrogen to the cleaved portion. For example, fatty acid triglycerides and fatty acids each have an oxygen-containing group such as an ester group and a carboxyl group, but hydrodeoxygenation removes oxygen atoms contained in these oxygen-containing groups, and the oxygen-containing organic compound is Converted to hydrocarbons. There are mainly two reaction pathways for hydrodeoxygenation of oxygen-containing groups of fatty acid triglycerides and the like. The first reaction route is a hydrogenation route that is reduced via an aldehyde or alcohol while maintaining the number of carbon atoms such as fatty acid triglyceride. In this case, oxygen atoms are converted to water. The second reaction route is a decarboxylation route in which oxygen-containing groups such as fatty acid triglycerides are eliminated as carbon dioxide as they are, and oxygen atoms are removed as carbon dioxide. In the hydrodeoxygenation in the present invention, these reactions proceed in parallel, and in the hydrotreating of the oil to be treated containing fats and oils derived from animals and plants, hydrocarbons, water, and carbon dioxide are generated. The hydrocarbon skeleton constituting the fatty acid unit such as fatty acid triglyceride is composed of an unsaturated and / or saturated long chain alkyl group, but the unsaturated bond of the hydrocarbon generated by hydrodeoxygenation is caused by hydrogenation treatment. It becomes a saturated bond substantially. In addition, sulfur-containing compounds, nitrogen-containing compounds and the like are removed by hydrogenation treatment. In addition, some side reactions such as decomposition reactions of the generated hydrocarbons also occur.

The hydrodeoxygenation step in the production method of the present invention may be composed of a single catalyst bed or may be composed of a plurality of catalyst beds. In addition, when the reaction zone is composed of a plurality of catalyst beds, the catalyst beds may be spaced apart in a single reactor, or a plurality of reactors arranged in series or in parallel. It may be installed inside.

As a form of the reactor in the hydrodeoxygenation step, a fixed bed system can be adopted. That is, hydrogen can adopt either a countercurrent or a parallel flow type with respect to the oil to be treated. Moreover, it is good also as a form which combined the countercurrent and the parallel flow using several reactors. As a general format, it is a down flow, and a gas-liquid twin parallel flow format can be adopted. Moreover, the reactor may be used alone or in combination, and a structure in which one reactor is divided into a plurality of catalyst beds may be adopted.

In the hydrodeoxygenation step, a porous inorganic oxide comprising two or more elements selected from the group consisting of aluminum, silicon, zirconium, boron, titanium and magnesium, and the porous inorganic oxide It is preferable to use a catalyst containing one or more metal elements belonging to any of Groups 6, 9, and 10 of the periodic table supported on the catalyst.

It is preferably an inorganic oxide containing aluminum as a constituent element of the porous inorganic oxide, that is, containing aluminum and other elements, and more preferably a composite oxide of aluminum oxide and other oxides. . In that case, the content of aluminum is preferably 1 to 97% by mass, more preferably 10 to 97% by mass, and still more preferably 20 to 95% by mass in terms of alumina oxide based on the total amount of the porous inorganic oxide. is there.

The porous inorganic oxide constituting the hydrogenation catalyst preferably further contains phosphorus as a constituent element. The phosphorus content is preferably 0.1 to 0.1, based on the total amount of the porous inorganic oxide.
It is 10 mass%, More preferably, it is 0.5-7 mass%, More preferably, it is 2-6 mass%. When the phosphorus content is less than 0.1% by mass, sufficient deoxygenation activity and desulfurization activity tend not to be exhibited. When the content exceeds 10% by mass, excessive decomposition reaction proceeds and the purpose is high. The yield of the resulting oil may be reduced.

The method for producing the porous inorganic oxide constituting the hydrogenation catalyst is not particularly limited. Examples of the raw material containing each constituent element include aluminum for aluminum hydroxide and boehmite, and silicon for silicic acid, water glass, Silica sol, boron, boric acid etc.
Titanium sulfide, titanium tetrachloride and various alkoxide salts can be used for titanium, zirconium sulfate and various alkoxide salts can be used for zirconium, and phosphoric acid and alkali metal salts of phosphoric acid can be used for phosphorus.

As a method for producing a porous inorganic oxide using these raw materials, for example, when aluminum is contained as one of the constituent elements, other constituent elements exemplified above for the prepared aluminum hydroxide gel are used. You may add the raw material to contain. Alternatively, in the process of adding water or an acidic aqueous solution to a commercially available aluminum oxide intermediate or boehmite powder and kneading, raw materials containing other constituent elements may be added, but at the stage of preparing aluminum hydroxide gel More preferably, these raw materials are allowed to coexist. It is preferable to produce a porous inorganic oxide by kneading these mixtures, molding them if necessary, drying them, and firing them.

The porous inorganic oxide as the carrier carries one or more active metals selected from elements included in Groups 6, 9, and 10 of the periodic table of elements. Here, the periodic table of elements is
This is a periodic table of elements specified by the International Union of Pure and Applied Chemistry (IUPAC). Preferred as active metals, Group 6 metal elements are chromium, molybdenum, and tungsten.
The group metal elements include cobalt, rhodium, and iridium, and the group 10 metal elements include nickel, palladium, and platinum. Among these active metals, it is preferable to use a combination of two or more metals selected from molybdenum, tungsten, cobalt and nickel. Examples of suitable combinations include cobalt-molybdenum, nickel-molybdenum, nickel-cobalt-molybdenum, and nickel-tungsten. Of these, combinations of nickel-molybdenum, nickel-cobalt-molybdenum, and nickel-tungsten are more preferred. When using these active metal-containing catalysts in the hydrodeoxygenation step, it is preferable to convert these metals into a sulfide state.

As the loading amount of the active metal based on the catalyst mass, molybdenum or tungsten is preferably 12 to 35 mass%, more preferably 15 to 30 mass% in terms of oxide. If the supported amount of molybdenum or tungsten is less than 12% by mass, the active sites tend to decrease and sufficient activity cannot be obtained. On the other hand, when it exceeds 35% by mass, the active metal is not effectively dispersed,
There is a tendency that sufficient activity cannot be obtained. The total supported amount of cobalt and / or nickel is preferably 1.0 to 15% by mass in terms of oxide, and more preferably 1.5 to 12% by mass. When the total supported amount of cobalt and / or nickel is less than 1.0% by mass, a sufficient promoter effect cannot be obtained and the activity tends to decrease. On the other hand, if it exceeds 15% by mass, the metal is not effectively dispersed and sufficient activity tends not to be obtained.

The method for incorporating these active metals into the catalyst is not particularly limited, and a known method applied when producing an ordinary desulfurization catalyst can be used. Usually, a method of impregnating a catalyst carrier with a solution containing a salt of an active metal is preferably employed. Also, equilibrium adsorption method, Pore-filli
The ng method, the incident-wetness method, and the like are also preferably employed. For example, P
The ore-filling method is a method in which the pore volume of a carrier is measured in advance and impregnated with a metal salt solution having the same volume. The impregnation method is not particularly limited, and it can be impregnated by an appropriate method according to the amount of metal supported and the physical properties of the catalyst carrier.

In the present invention, in order to maintain the catalytic activity of the hydrodeoxygenation step, the sulfur content flowing into the hydrodeoxygenation step is 1 mass ppm in the total fluid between the washing step and the hydrodeoxygenation step.
It is preferable that the sulfur compound and / or hydrogen sulfide is injected into the fluid by appropriately adjusting so as to achieve the above. The sulfur concentration is preferably 1 ppm by mass or more, more preferably in the range of 2 to 100 ppm by mass, and still more preferably in the range of 3 to 60 ppm by mass. When the sulfur concentration is less than 1 ppm by mass, the catalytic activity of the hydrodeoxygenation step decreases, and sufficient hydrodeoxygenation performance and olefin hydrogenation performance cannot be obtained. And oxygen content may increase. On the other hand, when the sulfur concentration is high, the sulfur content is mixed into the product oil to increase the sulfur content, or properties such as a doctor test and a copper plate corrosion test showing the quality as fuel may be deteriorated. In addition, the sulfur content in this invention means the mass content of the sulfur content measured based on the method of JISK2541 "Sulfur content test method" or ASTM-5453. The doctor test is measured in accordance with the method described in JIS K 2276 “Petroleum products-aviation fuel oil test method” or ASTM D-4952, and the copper plate corrosion test is performed in accordance with JIS K 2513 “Petroleum. It is measured according to the method described in “Product—Copper Plate Corrosion Test Method”.

Examples of the sulfur compound as a sulfur source used for adjusting the sulfur concentration include polysulfides, dialkyl disulfides, thiophenes, and mercaptans. Further, a fraction obtained by distilling crude oil may be mixed, and a refined fraction obtained by refining the fraction may be adjusted to a predetermined sulfur concentration. Further, hydrogen sulfide gas may be injected. Of these, polysulfides and dialkyl disulfides are preferred in consideration of the temperature at which the decomposition reaction occurs and the sulfidation efficiency of the active metal on the catalyst. Among dialkyl sulfides, dimethyl disulfide and dibutyl disulfide are preferred.

The reaction conditions in the hydrodeoxygenation step are preferably a hydrogen pressure of 1 to 10 MPa, a liquid hourly space velocity (LHSV) of 0.3 to 5.0 h ⁻¹ , and a hydrogen oil ratio (hydrogen / oil ratio) of 100 to 150.
0 NL / L, more preferably hydrogen pressure 2-8 MPa, liquid hourly space velocity 0.3-3.
0h ⁻¹ , hydrogen oil ratio 200 to 1200 NL / L, more preferably hydrogen pressure 2.
5-8 MPa, liquid hourly space velocity 0.5-2.5 h ⁻¹ , hydrogen oil ratio 250-1000 NL / L
It is. These conditions are factors that influence the reaction activity. For example, when the hydrogen pressure and the hydrogen oil ratio are less than the above lower limit values, the reactivity tends to decrease or the activity rapidly decreases. is there. On the other hand, when the hydrogen pressure and the hydrogen oil ratio exceed the above upper limit values, there is a tendency that excessive equipment investment such as a compressor is required. Further, the lower the liquid space velocity tends to be advantageous for the reaction, but if the liquid space velocity is less than the above lower limit value, there is a tendency that an extremely large internal volume reactor is required and excessive equipment investment is required, When the liquid space velocity exceeds the above upper limit, the reaction tends not to proceed sufficiently.

The reaction temperature in the hydrodeoxygenation step is preferably in the range of 200 to 390 ° C.
The range of 220 to 380 ° C is more preferable, and the range of 250 to 365 ° C is particularly preferable. When the reaction temperature is lower than 220 ° C., sufficient hydroisomerization reaction does not proceed, and when it is higher than 390 ° C., excessive decomposition, polymerization of raw material oil, and other side reactions may proceed. .

In the hydrodeoxygenation process, the hydrogen gas introduced into the reactor together with the feed oil is introduced from the inlet of the reactor along with the feed oil upstream or downstream of the heating furnace for raising the temperature to a predetermined reaction temperature. Apart from this, for the purpose of controlling the temperature in the reactor and maintaining the hydrogen pressure from upstream to downstream of the reactor, from between the catalyst beds,
Or when comprised with several reactors, you may introduce | transduce hydrogen gas from between the said reactors (quenching hydrogen). Alternatively, any or a combination of product oils, unreacted oils, reaction intermediate oils, etc., or a part of them, between the reactor inlet and the catalyst bed, or a plurality of reactors are used. It may be introduced in between. This controls the reaction temperature,
Excessive decomposition reactions and reaction runaway due to an increase in reaction temperature can be avoided.

In the production method of the present invention, the product oil obtained in the hydrodeoxygenation step is mainly composed of linear hydrocarbons, and an isomerization step is provided to improve low temperature performance after the hydrodeoxygenation step. Also good. In the isomerization step, a generally known isomerization catalyst can be used. For example,
As the carrier constituting the isomerization catalyst, a porous inorganic oxide may be selected, and it is more preferable that at least two elements selected from aluminum, silicon, zirconium and titanium are included. The porous inorganic oxide may be amorphous or crystalline,
Zeolite can also be used. When using zeolite, among the structure codes defined by the International Zeolite Society, FAU, BEA, MOR, MFI, MEL, MWW, TON,
It is preferable to use a zeolite having a crystal structure such as AEL or MTT. In addition, the active metal of the isomerization catalyst is preferably one or more metals selected from the elements of Group 8, Group 9, Group 10 and Group 11 of the Periodic Table of Elements. More preferably, it is one or more metals selected from palladium, ruthenium, rhodium, gold, irdium, nickel, and cobalt, and particularly preferably platinum, palladium, ruthenium, and nickel. In addition, these active metals may combine two or more types of metals, and examples include platinum-palladium, platinum-ruthenium, platinum-rhodium, platinum-gold, and platinum-iridium. The product obtained in the isomerization step can be obtained by removing light hydrocarbons as decomposition products by distillation or the like to obtain a predetermined hydrocarbon oil.

(Production oil)
In the hydrodeoxygenation step in the production method of the present invention, a hydrogenation reaction of an olefin derived from an unsaturated fatty acid structure contained in fats and oils occurs in addition to the hydrodeoxygenation reaction. The olefin content can be quantified by iodine value. The iodine value in the present invention is JIS
This is a value measured in accordance with the method described in K 0070 “Testing Method for Acid Value, Saponification Value, Ester Value, Iodine Value, Hydroxyl Value and Unsaponified Product of Chemical Products”. About the product oil which processed the acid washing process oil by the hydrodeoxygenation process, it is preferable that the iodine value of a product oil is 0.1 g-I < ₂ > / g or less from a viewpoint of oxidation stability. When the iodine value exceeds 0.1 g-I ₂ / g or less, the oxidation stability is deteriorated and the acid value described above tends to increase remarkably.

The oxidation stability of the product oil can be determined quantitatively by the amount of increase in the acid value after blowing oxygen gas into the oil sample at 115 ° C. for 16 hours, based on the acid value before blowing oxygen gas. it can. The acid value increase amount of the produced oil is preferably 0.25 mg-KOH / g or less, and more preferably 0.15 mgKOH / g or less. The acid value is an index representing the amount of acidic components in 1 g of a sample, and when the increase in acid value exceeds 0.25 mgKOH / g, the storage stability of the product oil tends to deteriorate. The “acid value” in the present invention is JIS K 2
It means the acid value measured according to the method described in 276 “Petroleum products—aviation fuel oil test method”.

The hydrocarbon oil obtained by the production method of the present invention can be suitably used particularly as a diesel light oil or heavy oil base material. In this case, the hydrocarbon oil produced by the method of the present invention may be used alone as a diesel light oil or heavy oil base material, but used as a diesel light oil or heavy base material mixed with components such as other base materials. Can do. As other base materials, a light oil fraction and / or kerosene fraction obtained in a general petroleum refining process and a residual fraction obtained by the method for producing a hydrocarbon oil of the present invention can be mixed. Furthermore, so-called synthesis gas composed of hydrogen and carbon monoxide is used as a raw material, and synthetic light oil or synthetic kerosene obtained through a Fischer-Tropsch reaction or the like can be mixed. These synthetic light oils and kerosene are characterized by containing almost no aromatic content, having a saturated hydrocarbon as a main component, and a high cetane number. In addition, a well-known method can be used as a manufacturing method of synthesis gas, and it is not specifically limited.

EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example at all.

[Washing process]
Example 1
Using crude palm oil as a raw material oil, adding 3% by weight sulfuric acid aqueous solution with respect to the raw material oil mass while heating and stirring at 75 ° C. and holding for 20 minutes, followed by centrifugation at 3000 × G for 15 minutes. Separation was performed, and liquid A, which was a separated oil phase, was recovered. The sulfuric acid concentration in the sulfuric acid aqueous solution added at the time of washing was 1.7% by mass based on the aqueous solution.

(Example 2)
A liquid B was obtained in the same manner as in Example 1 except that a phosphoric acid aqueous solution was used instead of the sulfuric acid aqueous solution. The phosphoric acid concentration in the phosphoric acid aqueous solution was 1.7% by mass based on the aqueous solution.

(Example 3)
Liquid C was prepared in the same manner as in Example 1 except that a citric acid aqueous solution was used instead of the sulfuric acid aqueous solution.
Got. The citric acid concentration in the citric acid aqueous solution was 1.7% by mass based on the aqueous solution.

Example 4
A liquid D was obtained in the same manner as in Example 1 except that an acetic acid aqueous solution was used instead of the sulfuric acid aqueous solution. The acetic acid concentration in the aqueous acetic acid solution was 1.7% by mass based on the aqueous solution.

(Example 5)
Using crude palm oil as a raw material oil, adding 100% by weight sulfuric acid aqueous solution to the raw material oil mass while heating and stirring at 75 ° C., holding it for 20 minutes, and allowing to stand, recovering the separated oil phase Thus, liquid E was obtained. The sulfuric acid concentration in the sulfuric acid aqueous solution was 1.7% by mass.

(Example 6)
While the liquid A obtained in Example 1 was heated and stirred at 75 ° C., 3% by mass of water was added to the mass of the liquid A and held for 20 minutes, and then the same centrifugal operation as in Example 1 was performed. As a result, an oily phase liquid F was obtained.

(Example 7)
Using crude palm oil as a raw material oil, while heating and stirring at 75 ° C., a 3% by weight sulfuric acid aqueous solution is added to the raw material oil weight, and the mixture is held for 20 minutes. Got. The sulfuric acid concentration in the sulfuric acid aqueous solution was 1.7% by mass.

(Example 8)
A liquid H was obtained in the same manner as in Example 1 except that the mixing temperature with the sulfuric acid aqueous solution was set to 97 ° C. The sulfuric acid concentration in the aqueous sulfuric acid solution was 1.7% by mass based on the aqueous solution.

(Comparative Example 1)
No crude palm oil was washed.

(Comparative Example 2)
Using crude palm oil as a raw material oil, adding 3% by weight sulfuric acid aqueous solution to the raw material oil mass while heating and stirring at 30 ° C. and holding it for 20 minutes, followed by centrifugation at 3000 × G for 15 minutes. Separation was performed, and liquid I, which was a separated oil phase, was recovered. The sulfuric acid concentration in the sulfuric acid aqueous solution added at the time of washing was 1.7% by mass based on the aqueous solution.

(Comparative Example 3)
200 g of strong acid cation exchange resin, manufactured by Rohm and Haas “Amberlyst 1
5 ”(trade name) is packed in a jacketed column and this is kept warm with 35 ° C. warm water.
Crude palm oil kept at 5 ° C. was passed through to obtain liquid J as a distillate.

Tables 1 and 2 show the contents of impurities such as the metal content of each of the liquids A to J that have been subjected to the cleaning treatment obtained in the cleaning step in the above examples or comparative examples.

From Tables 1 and 2, in Examples 1 to 8, the content of alkali metal, alkaline earth metal and transition metal can be reduced to a sufficient level by washing treatment with an acid aqueous solution, In Comparative Example 2 where the temperature of the cleaning treatment was low and in Comparative Example 3 where the treatment with the ion exchange resin was performed, it was revealed that the metal component was not sufficiently removed. Further, when the centrifugation operation is not performed (Example 5), an increase in the residual concentration of phosphorus and iron is observed.
Furthermore, in Example 8 which performed washing | cleaning at 97 degreeC, although the production | generation of the brown insoluble content was seen in the raw material oil after washing | cleaning, the said metal content was fully removed.

(Preparation of catalyst for hydrodeoxygenation process)
Water glass No. 3 was added to an aqueous solution of sodium aluminate having a concentration of 5% by mass and placed in a container kept at 65 ° C. On the other hand, a solution obtained by adding phosphoric acid (concentration 85%) to an aqueous solution of aluminum sulfate having a concentration of 2.5 mass% in another container kept at 65 ° C. was prepared, and the aqueous solution containing sodium aluminate was added dropwise thereto. . The time when the pH of the mixed solution reached 7.0 was set as the end point, and the resulting slurry product was filtered through a filter to obtain a cake slurry. Next, the cake-like slurry was transferred to a container equipped with a reflux condenser, and 150 ml and 27 ml of distilled water were added.
A 10% aqueous ammonia solution was added, and the mixture was stirred with heating at 75 ° C. for 20 hours. The slurry was put in a kneading apparatus and heated to 80 ° C. or higher and kneaded while removing moisture to obtain a clay-like kneaded product. The obtained kneaded material was extruded into the shape of a cylinder having a diameter of 1.5 mm by an extrusion molding machine.
After drying at 0 ° C. for 1 hour, it was fired at 550 ° C. to obtain a shaped carrier. An impregnating solution containing 50 g of the obtained shaped carrier in an eggplant type flask and containing molybdenum trioxide, nickel (II) nitrate hexahydrate, phosphoric acid (concentration 85% by mass) and malic acid while degassing with a rotary evaporator. Was poured into the flask. The impregnated solid was dried at 120 ° C. for 1 hour and then calcined at 550 ° C. to obtain a catalyst. The composition of the prepared catalyst is shown in Table 3.

(Preparation of hydrogenation catalyst)
A reaction tube (inner diameter 20 mm) filled with the catalyst (20 ml) was attached to a fixed bed flow type reactor. A straight-run gas oil (sulfur content: 3% by mass) obtained by adding dimethyl disulfide to the catalyst layer was mixed with an average catalyst layer temperature of 300 ° C., a hydrogen partial pressure of 6 MPa, a liquid space velocity of 1 h ⁻¹ , and a hydrogen / oil ratio of 200 NL / L. The catalyst was presulfided for 4 hours under these conditions.

(Examples 9 to 12, Comparative Examples 4 and 5)
In Examples 9 to 12, the liquids A, B, C and H, which are the cleaning oils obtained in Examples 1 to 3 and 8, were used. In Comparative Examples 4 and 5, the unwashed process obtained in Comparative Examples 1 and 2 Liquid HI, which is oil or cleaning oil, was subjected to a hydrodeoxygenation step as a raw material oil. In the hydrodeoxygenation step, dimethyl disulfide previously added to each raw material oil so as to have a sulfur concentration of 10 mass ppm is used, and these are passed through the catalyst layer, respectively, and hydrogen pressure: 5. 0 MPa,
LHSV (liquid hourly space velocity): 1.0 h ⁻¹ , hydrogen oil cost: 800 NL / L, reaction temperature: 28
Hydrodeoxygenation treatment was performed at 0 ° C. The properties of unwashed palm oil were as follows: density at 15 ° C .: 0.916 g / ml, oxygen content: 11.4% by mass.

Table 4 shows the oxygen content removal rate, olefin hydrogenation rate, and oxidation stability of the product oil in the hydrodeoxygenation step when each raw material oil is used.

As used herein, “oxygen removal rate” refers to a value defined by the following equation.
Oxygen content removal rate (%) = 100 − {(Oxygen content of product oil after hydrodeoxygenation step) / (Oxygen content of raw material oil)} × 100
In addition, the “oxygen content” in the raw material oil and the product oil here refers to an oxygen content measured in accordance with the method described in UOP-649.

The “olefin hydrogenation rate” is a value defined by the following formula.
Olefin hydrogenation rate (%) = 100 − {(Production iodine value after hydrodeoxygenation step) / (Iodine value of feedstock)} × 100

Furthermore, the increase in acid value, which is an index of oxidation stability, was measured by the following method. That is, the acid value before and after the oxidation acceleration test is measured according to the method described in the acid value test method in JIS K 2276 “Petroleum products—aviation fuel oil test method”, and the oil value is determined from the acid value after the acceleration test. The amount of increase was determined by subtracting the acid value of. In the oxidation acceleration test, an operation was performed in which the generated oil was kept at 115 ° C. and oxygen gas was blown for 16 hours.

As is apparent from Table 4, in Examples 9 to 12 in which the alkali metal content, alkaline earth metal content and transition metal content were sufficiently removed, the hydrodeoxygenation activity and olefin hydrogen of the catalyst in the hydrodeoxygenation step It was confirmed that the oxidization activity was maintained at a sufficiently high level, and the product oil had a sufficiently high oxygen removal rate and excellent oxidation stability. On the other hand, in Comparative Examples 4 and 5, the hydrodeoxygenation reaction and the olefin hydrogenation reaction did not proceed sufficiently, the product oil oxygen content removal rate was low, the unsaturated content was large, and the oxidation stability was insufficient. It was.

Claims (8)

A raw material oil containing an oil and fat component derived from animals and plants is contact-mixed with an acid aqueous solution so that the total content of alkali metal, alkaline earth metal and transition metal in the raw oil is 15 mass ppm or less. A washing step for washing the raw material oil;
A hydrodeoxygenation step in which the raw material oil washed in the washing step is brought into contact with a hydrogenation catalyst under hydrogen pressure to produce a hydrocarbon oil;
Equipped with a,
In the washing step, the temperature when the raw material oil and the acid aqueous solution are contact-mixed is 40 to 100 ° C. The method for producing a hydrocarbon oil according to claim 1, wherein the acid aqueous solution contains at least one selected from the group consisting of phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, acetic acid, citric acid, and tartaric acid. . The washing step
A contact mixing step of contacting and mixing the raw oil and the acid aqueous solution;
Characterized in that it comprises a centrifugation step of performing centrifugal separation on the mixture obtained in the contacting mixing step, producing a hydrocarbon oil according to claim 1 or 2. The amount of the acid solution in the cleaning process, characterized in that from 0.01 to 20 wt% with respect to the feed oil, a hydrocarbon oil according to any one of claims 1 to 3 Production method. The hydrogenation catalyst,
A porous inorganic oxide comprising two or more elements selected from the group consisting of aluminum, silicon, zirconium, boron, titanium and magnesium;
One or more metal elements belonging to any one of Group 6, Group 9, and Group 10 of the periodic table of elements supported on the porous inorganic oxide;
The method for producing a hydrocarbon oil according to any one of claims 1 to 4 , wherein the hydrocarbon oil is contained. The method for producing a hydrocarbon oil according to claim 5 , wherein the porous inorganic oxide further contains phosphorus as a constituent element. Wherein the iodine value of the hydrocarbon oil obtained by the hydrodeoxygenation step is equal to or less than 0.1g-I 2 _/ 100g, a hydrocarbon oil according to any one of claims 1 to 6 Manufacturing method. The increase in acid value after blowing oxygen gas at 115 ° C. for 16 hours into the hydrocarbon oil obtained in the hydrodeoxygenation step is 0.25 mg-KOH / g or less based on the acid value before blowing oxygen gas and characterized in that, the production method of the hydrocarbon oil according to any one of claims 1-7.