CN101705313A - Method for removing catalysts from polypentaose-containing plant acidolysis solution - Google Patents
Method for removing catalysts from polypentaose-containing plant acidolysis solution Download PDFInfo
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- CN101705313A CN101705313A CN200910235695A CN200910235695A CN101705313A CN 101705313 A CN101705313 A CN 101705313A CN 200910235695 A CN200910235695 A CN 200910235695A CN 200910235695 A CN200910235695 A CN 200910235695A CN 101705313 A CN101705313 A CN 101705313A
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Abstract
The invention provides a method for removing catalyst-sulfuric acid from polypentaose-containing plant acidolysis solution, which comprises the steps: firstly, decolorizing the polypentaose-containing plant acidolysis solution and removing iron ions; and removing sulfuric acid by an electrodialysis device to obtain the purified solution of the acidolysis solution. By controlling operational parameters of electrodialysis, the method not only settles the problem about the removal of electrolytes from the acidolysis solution, but can also recover the catalyst-sulfuric acid for acidolysis reaction, the procedure of cleaning dilute sulfuric acid before the hydrolysis of sulfuric acid is implemented to realize wastewater-free discharge in the procedure of electrodialysis, and therefore, the cost of unit product is lowered. The method solves the problem of the discharge of solid waste-calcium sulfate in traditional processes and reduces the considerable consumption of acid and base and the treatment amount of environmental-friendly wastewater in the using process of ion exchange resin.
Description
Technical field
The present invention relates to a kind of method of from contain poly pentose plant acid hydrolysis solution, removing catalyzer.
Background technology
Wood sugar is at China's knowhow of existing four more than ten years, and technical reaching world standard has been world's xylose production and big export country, along with expanding economy and growth in the living standard, the domestic market constantly enlarges, and further develops wood sugar, has very superior condition.China is large agricultural country, produces 1.2 hundred million tons of corns per year, and the output of corn cob accounts for 1/4th of corn yield, about 3,000 ten thousand tons; China produces about 8,000,000 tons of sucrose, about 9,000,000 tons of sugared slag per year; China produces 1.2 hundred million tons of maize straws per year; In addition, bamboo contains poly pentose 20-25%, bamboo wood papermaking and comprehensive utilization wood sugar can be combined, and this will be a kind of potential wood sugar resource.
At present, produce wood sugar and generally adopt comparatively traditional production technique, mainly be will contain the raw material of poly pentose through washing, hydrolysis, decolouring, neutralization, ion-exchange, concentrate, ion-exchange and the refining wood sugar of step such as concentrate, the production of production crystallization afterwards xylose product.This kind production technique, the acid and alkali consumption amount is big in the production process, has problems such as " three wastes " exhaust emission environment.Because country advocates and sets up energy-saving and emission-reduction and friendly environment society, so traditional production technique has been proposed serious challenge.
Therefore, need each link of xylose production be studied, reduce discharging, reduce pollution, reduce cost environment at the problems referred to above.
Summary of the invention
The purpose of this invention is to provide a kind of method of from contain poly pentose plant acid hydrolysis solution, removing catalyzer, solve the discharging of solid waste-calcium sulfate in the traditional technology, reduced the mass consumption and the environment-protection wastewater treatment capacity of soda acid in the ion exchange resin use.
In order to realize the object of the invention, a kind of method of from contain poly pentose plant acid hydrolysis solution, removing catalyzer of the present invention, it comprises the steps:
1) will contain poly pentose plant acid hydrolysis solution earlier decolours and removes iron ion;
2) remove sulfuric acid by electrodialysis unit then, obtain the scavenging solution of acid hydrolysis solution.
Wherein, describedly contain poly pentose plant acid hydrolysis solution to adopt one or more (containing two kinds) of containing poly pentose plant with corn cob, stalk, bagasse, bamboo etc. be raw material, after removal of impurities, rinsing, hot water wash, dilute sulfuric acid dip, obtain through sulphuric acid hydrolysis.
The employing hydrolysising condition is: the sulfuric acid add-on is the 0.5-1.5% of material quantity, and hydrolysis temperature is 90-130 ℃, hydrolysis time 1-4 hour.
Described decolouring adopts gac to handle, the gac that gac selects for use zinc chloride process to produce, and add-on is that (mass volume ratio g/100ml), makes the transmittance of its destainer reach 75-90% for the 0.1-0.5% of acid hydrolysis solution volume.
Described removal iron ion adopts and adds organic complexing agent; described organic complexing agent is one or more in disodium ethylene diamine tetraacetate, tetrasodium ethylenediamine tetraacetate, 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid, nitrilotriacetic acid(NTA) and the thionamic acid sodium; add-on is the long-pending 0.05-0.5% (mass volume ratio of sulfolysis liquid; g/100ml); the content of the iron ion in the destainer is lower than 10ppm; the protection electrodialysis is not contaminated, improves electrodialytic working efficiency, prolongs electrodialytic work-ing life.
The present invention removes sulfuric acid by electrodialysis, adopts the anion and cation exchange membrane of hyposmosis, and the processing parameter in the strict control condiments process: voltage, electric current, pressure and temperature, and to improve the yield of wood sugar.
The ion-exchange membrane of a kind of low-permeability that the negative and positive film in the described electrodialysis unit adopts, the rejection of control pentose is more than 97%.It is electric drive membrane, anode membrane exchange capacity 〉=2.0mol/kg, cavity block exchange capacity 〉=1.8mol/kg, thermostability≤40 ℃, chemical stability pH1-10, water transmitance≤0.2ml/h.cm
2, select transmitance 〉=90%.
The condition of described electrodialysis unit: volts DS is controlled to be 0.5-1.0v/ to film, temperature 30-40 ℃, utmost point water (polarized water) specific conductivity is 5000-10000 μ s/cm, tap water magnitude of recruitment in the dense water pot is the 20-60% of inlet amount, the discharging when specific conductivity in the dense water pot reaches 3-5 times of feeding liquid specific conductivity.
Behind the strong electrolyte in the acid hydrolysis solution of electrodialysis process, be mainly the sulfuric acid of content 0.6-1.2% in the dense water of generation, also contain some other zwitterion.
The dense water that electrodialysis produces is concentrated recovery, the dense water of electrodialysis that reclaims is made into the dilution heat of sulfuric acid of 0.05-0.2%, can be used for the poly pentose plant material before the sulphuric acid hydrolysis is carried out the dilute sulphuric acid pretreatment technology, remove ash content and part colloid, the protein etc. carried secretly in the raw material, help the processing of raw material sulphuric acid hydrolyzed solution postchannel process.
Through after the electrodialysis process, sulfate radical clearance in the raw material sulphuric acid hydrolyzed solution reaches more than 95%, the wood sugar liquid of removing most of sulfate radical and inorganic salt is again through concentrating, carry out biological fermentation at last and get xylitol products, or again through ion-exchange removal weak electrolyte wherein, concentrated at last, crystallization gets xylose product.
The present invention adopts neutralization and the ion exchange process in the electrodialysis replacement traditional technology, has saved solid waste and acid and alkali consumption greatly, not only production environment cleaning, and also energy-saving and emission-reduction in the production process, environmental friendliness.
The present invention is by the processing parameter in the control electrodialysis operational process, solved that to contain poly pentose Plant Transformation be the problem of environmental pollution that exists in the wood sugar.It can reduce the environment-protection wastewater treatment capacity, can also improve cost and quality that raw material hydrolyzed solution postchannel process is handled.
Embodiment
Following examples are used to illustrate the present invention, but are not used for limiting the scope of the invention.
Embodiment 1
1, with the corn cob is raw material, through removal of impurities, rinsing, 80 ℃ of hot water wash, add 0.2% dilute sulfuric acid dip after, carry out sulphuric acid hydrolysis at 1: 5 by solid-to-liquid ratio, hydrolysising condition: sulfuric acid content 1.0%, 120 ℃ of hydrolysis temperatures, hydrolysis time 2 hours, hydrolysis is carried out solid-liquid separation after finishing, and filtrate is sulphuric acid hydrolysis liquid;
2, sulphuric acid hydrolysis liquid is passed through decolouring and removal iron ion, the gac that powder carbon selects for use zinc chloride process to produce, powder carbon dosage is 0.3% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), make the transmittance of its destainer reach 75%, the organic complexing agent of removing iron ion is a disodium ethylene diamine tetraacetate, dosage is 0.1% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), the content of the iron ion in the destainer is lower than 10ppm, the protection electrodialysis is not contaminated, improves electrodialytic working efficiency, prolongs electrodialytic work-ing life;
3,, obtain the scavenging solution of sulphuric acid hydrolysis liquid by the catalyzer-sulfuric acid in the electrodialysis removal sulphuric acid hydrolysis liquid;
Negative and positive film in the electrodialysis unit is a kind of ion-exchange membrane of low-permeability, and the rejection of control pentose is more than 97%.
Electrodialytic operational condition: volts DS 0.7v/ is to film, 40 ℃ of temperature, utmost point water conductivity is 5000 μ s/cm, tap water magnitude of recruitment in the dense water pot is 40% of an inlet amount, the discharging when specific conductivity in the dense water pot reaches 3 times of feed liquid specific conductivity. after adopting the strong electrolyte in the electrodialysis process sulphuric acid hydrolysis liquid, the sulfuric acid of main content 0.7% also contains some other zwitterion in the dense water that produces;
4, the dense water that electrodialysis is produced is concentrated and is reclaimed, the dense water of electrodialysis that reclaims is made into 0.1% dilution heat of sulfuric acid, be used for the raw material before the sulphuric acid hydrolysis is carried out the dilute sulphuric acid pretreatment technology, remove ash content and part colloid, the protein etc. carried secretly in the raw material, help the processing of raw material sulphuric acid hydrolyzed solution postchannel process.
Through after the electrodialysis process, sulfate radical clearance in the raw material sulphuric acid hydrolyzed solution reaches more than 95%, the wood sugar liquid of removing most of sulfate radical and inorganic salt is again through concentrating, carry out biological fermentation at last and get xylitol products, or again through ion-exchange removal weak electrolyte wherein, concentrated at last, crystallization gets xylose product.
Embodiment 2
1, with stalk and bagasse to be mixed into raw material at 1: 1, after removal of impurities, rinsing, 100 ℃ of hot water wash, 0.3% dilute sulfuric acid dip, carry out sulphuric acid hydrolysis at 1: 6 by solid-to-liquid ratio, hydrolysising condition: sulfuric acid content 0.9%, 115 ℃ of hydrolysis temperatures, hydrolysis time 3h, hydrolysis is carried out solid-liquid separation after finishing, and filtrate is sulphuric acid hydrolysis liquid;
2, sulphuric acid hydrolysis liquid is passed through decolouring and removal iron ion, the gac that powder carbon selects for use zinc chloride process to produce, powder carbon dosage is 0.4% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), make the transmittance of its destainer reach 80%, the organic complexing agent of removing iron ion is a 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid, dosage is 0.2% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), the content of the iron ion in the destainer is lower than 10ppm, the protection electrodialysis is not contaminated, improves electrodialytic working efficiency, prolongs electrodialytic work-ing life;
3,, obtain the scavenging solution of sulphuric acid hydrolysis liquid by the catalyzer-sulfuric acid in the electrodialysis removal sulphuric acid hydrolysis liquid;
Negative and positive film in the electrodialysis unit is a kind of ion-exchange membrane of low-permeability, and the rejection of control pentose is more than 97%.
Electrodialytic operational condition: volts DS 0.8v/ is to film, 30 ℃ of temperature, and utmost point water conductivity is 6000 μ s/cm, the tap water magnitude of recruitment in the dense water pot is 50% of an inlet amount, the discharging when specific conductivity in the dense water pot reaches 4 times of feed liquid specific conductivity.After adopting the strong electrolyte in the electrodialysis process sulphuric acid hydrolysis liquid, the sulfuric acid of main content 0.8% also contains some other zwitterion in the dense water of generation;
4, the dense water that electrodialysis is produced is concentrated and is reclaimed, the dense water of electrodialysis that reclaims is made into 0.15% dilution heat of sulfuric acid, be used for the raw material before the sulphuric acid hydrolysis is carried out the dilute sulphuric acid pretreatment technology, remove ash content and part colloid, the protein etc. carried secretly in the raw material, help the processing of raw material sulphuric acid hydrolyzed solution postchannel process.
Embodiment 3
1, with the stalk is raw material, after removal of impurities, rinsing, 90 ℃ of hot water wash, 0.2% dilute sulfuric acid dip, carries out sulphuric acid hydrolysis at 1: 5 by solid-to-liquid ratio, hydrolysising condition: sulfuric acid content 0.8%, 110 ℃ of hydrolysis temperatures, hydrolysis time 2.5h, hydrolysis is carried out solid-liquid separation after finishing, and filtrate is sulphuric acid hydrolysis liquid;
2, sulphuric acid hydrolysis liquid is passed through decolouring and removes iron ion, the gac that powder carbon selects for use zinc chloride process to produce, powder carbon dosage is 0.3% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), make the transmittance of its destainer reach 80%, the organic complexing agent of removing iron ion is disodium ethylene diamine tetraacetate and tetrasodium ethylenediamine tetraacetate (weight ratio 1: 1), dosage is 0.25% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), the content of the iron ion in the destainer is lower than 10ppm, the protection electrodialysis is not contaminated, improves electrodialytic working efficiency, prolongs electrodialytic work-ing life;
3,, obtain the scavenging solution of sulphuric acid hydrolysis liquid by the catalyzer-sulfuric acid in the electrodialysis removal sulphuric acid hydrolysis liquid;
Negative and positive film in the electrodialysis unit is a kind of ion-exchange membrane of low-permeability, and the rejection of control pentose is more than 97%.
Electrodialytic operational condition: volts DS 0.8v/ is to film, 30 ℃ of temperature, and utmost point water conductivity is 5000 μ s/cm, the tap water magnitude of recruitment in the dense water pot is 50% of an inlet amount, the discharging when specific conductivity in the dense water pot reaches 4 times of feed liquid specific conductivity.After adopting the strong electrolyte in the electrodialysis process sulphuric acid hydrolysis liquid, the sulfuric acid of main content 0.8% also contains some other zwitterion in the dense water of generation;
4, the dense water that electrodialysis is produced is concentrated and is reclaimed, the dense water of electrodialysis that reclaims is made into 0.15% dilution heat of sulfuric acid, be used for the raw material before the sulphuric acid hydrolysis is carried out the dilute sulphuric acid pretreatment technology, remove ash content and part colloid, the protein etc. carried secretly in the raw material, help the processing of raw material sulphuric acid hydrolyzed solution postchannel process.
Embodiment 4
1, with the bamboo is raw material, after removal of impurities, rinsing, 100 ℃ of hot water wash, 0.2% dilute sulfuric acid dip, carry out sulphuric acid hydrolysis at 1: 5 by solid-to-liquid ratio, hydrolysising condition: sulfuric acid content 0.9%, 108 ℃ of hydrolysis temperatures, hydrolysis time 2.5h, hydrolysis is carried out solid-liquid separation after finishing, and filtrate is sulphuric acid hydrolysis liquid;
2, sulphuric acid hydrolysis liquid is passed through decolouring and removal iron ion, the gac that powder carbon selects for use zinc chloride process to produce, powder carbon dosage is 0.25% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), make the transmittance of its destainer reach 75%, the organic complexing agent of removing iron ion is a nitrilotriacetic acid(NTA), dosage is 0.15% long-pending (mass volume ratio of sulphuric acid hydrolysis liquid, g/100ml), the content of the iron ion in the destainer is lower than 10ppm, the protection electrodialysis is not contaminated, improves electrodialytic working efficiency, prolongs electrodialytic work-ing life;
3,, obtain the scavenging solution of sulphuric acid hydrolysis liquid by the catalyzer-sulfuric acid in the electrodialysis removal sulphuric acid hydrolysis liquid;
Negative and positive film in the electrodialysis unit is a kind of ion-exchange membrane of low-permeability, and the rejection of control pentose is more than 97%.
Electrodialytic operational condition: volts DS 0.7v/ is to film, 40 ℃ of temperature, and utmost point water conductivity is 5000 μ s/cm, the tap water magnitude of recruitment in the dense water pot is 40% of an inlet amount, the discharging when specific conductivity in the dense water pot reaches 3 times of feed liquid specific conductivity.After adopting the strong electrolyte in the electrodialysis process sulphuric acid hydrolysis liquid, the sulfuric acid of main content 0.7% also contains some other zwitterion in the dense water of generation;
4, the dense water that electrodialysis is produced is concentrated and is reclaimed, the dense water of electrodialysis that reclaims is made into 0.1% dilution heat of sulfuric acid, be used for the raw material before the sulphuric acid hydrolysis is carried out the dilute sulphuric acid pretreatment technology, remove ash content and part colloid, the protein etc. carried secretly in the raw material, help the processing of raw material sulphuric acid hydrolyzed solution postchannel process.
Though above the present invention is described in detail with a general description of the specific embodiments, on basis of the present invention, can make some modifications or improvements it, this will be apparent to those skilled in the art.Therefore, these modifications or improvements all belong to the scope of protection of present invention without departing from theon the basis of the spirit of the present invention.
Claims (7)
1. a method of removing catalyzer from contain poly pentose plant acid hydrolysis solution is characterized in that it comprises the steps:
1) will contain poly pentose plant acid hydrolysis solution earlier decolours and removes iron ion;
2) remove sulfuric acid by electrodialysis unit then, obtain the scavenging solution of acid hydrolysis solution.
2. method according to claim 1, it is characterized in that, the described poly pentose plant acid hydrolysis solution that contains adopts with one or more of corn cob, stalk, bagasse, bamboo to be raw material, after removal of impurities, rinsing, hot water wash, dilute sulfuric acid dip, to obtain through sulphuric acid hydrolysis.
3. method according to claim 1 and 2 is characterized in that, described decolouring adopts gac to handle, and add-on is the 0.1-0.5% of acid hydrolysis solution volume.
4. according to any described method of claim 1-3, it is characterized in that described removal iron ion adopts and adds organic complexing agent, add-on is the long-pending 0.05-0.5% of sulfolysis liquid.
5. method according to claim 4 is characterized in that, described organic complexing agent is one or more in disodium ethylene diamine tetraacetate, tetrasodium ethylenediamine tetraacetate, 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid, nitrilotriacetic acid(NTA), the thionamic acid sodium.
6. according to any described method of claim 1-5, it is characterized in that described electrodialysis unit adopts the ion-exchange membrane of low-permeability.
7. method according to claim 6, it is characterized in that, the condition of described electrodialysis unit: volts DS is controlled to be 0.5-1.0v/ to film, temperature 30-40 ℃, utmost point water conductivity is 5000-10000 μ s/cm, tap water magnitude of recruitment in the dense water pot is the 20-60% of inlet amount, the discharging when specific conductivity in the dense water pot reaches 3-5 times of feeding liquid specific conductivity.
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| WO2013113323A1 (en) | 2012-01-31 | 2013-08-08 | Syral Belgium Nv | Process for extraction of pentose from ligno-cellulosic substrate |
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| CN1020042C (en) * | 1988-11-12 | 1993-03-10 | 福建省漳州糖厂 | Process for preparing crystalline xylose |
| KR101108789B1 (en) * | 2007-02-09 | 2012-03-13 | 씨제이제일제당 (주) | A method for xylitol production using the hydrolysate containing xylose and arabinose prepared from byproduct of tropical fruit biomass |
| CN101392009B (en) * | 2007-09-21 | 2011-05-11 | 山东龙力生物科技股份有限公司 | Novel production technique of xylose |
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| WO2013113323A1 (en) | 2012-01-31 | 2013-08-08 | Syral Belgium Nv | Process for extraction of pentose from ligno-cellulosic substrate |
| US9493850B2 (en) | 2012-01-31 | 2016-11-15 | Syral Belgium Nv | Process for extraction of pentose from ligno-cellulosic substrate |
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