CN206168241U - Splitter of acetylpropionic acid class compound - Google Patents

Splitter of acetylpropionic acid class compound Download PDF

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Publication number
CN206168241U
CN206168241U CN201621079203.5U CN201621079203U CN206168241U CN 206168241 U CN206168241 U CN 206168241U CN 201621079203 U CN201621079203 U CN 201621079203U CN 206168241 U CN206168241 U CN 206168241U
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membrane
acetyl
layer
propionic acid
film
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宋奇
孔德金
郑均林
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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Abstract

The utility model relates to a splitter of acetylpropionic acid class compound, mainly solve prior art exist in the acetylpropionic acid class compound purge process yield low with the high problem of energy consumption. The utility model discloses an adopt longshore current body flow direction to include prefiltering layer, ultrafiltration layer and reverse osmosis layer at least, wherein, the prefiltering layer is filter paper membrane or ceramic filter membrane, the ultrafiltration layer is polyvinylidene fluoride membrane, polyvinyl chloride membrane, polysulfone (PSO) membrane, polysulfonamide membrane, polycarbonate membrane or polystyrene film, the reverse osmosis layer is that the technical scheme of the complex film of cellulose acetate membrane, polyamide membrane or cellulose acetate and polyamide has solved this problem betterly, among the industrial production of the acetylpropionic acid class compound that can be used to to purify.

Description

The separation equipment of acetyl-propionic acid compound
Technical field
This utility model is related to a kind of separation equipment of acetyl-propionic acid compound.
Background technology
Modern chemical industry produces substantial amounts of fuels and chemicals based on fossil resource, has greatly promoted society Development and progress.In the long run, as non-renewable physical resources, fossil resource reserves are limited.Fossil resource can not be again Natural disposition, promotes people actively to find and develop renewable resources, and continuously production meets growing social need.It is raw Material have received extensive concern as a large amount of reproducible physical resources.Levulic acid (LA, LA or penta Every keto acid) it is important biomass platform chemicals, low toxicity has to be distilled under hygroscopicity, normal pressure and hardly decomposes, and intramolecular contains Abundant functional group, it is easy to which esterification, hydrogenation, condensation, oxidation and the series of chemical such as halogenation occur, be prepare it is various high attached The important intermediate of value added chemical products, is widely used in the industry neck such as spice, solvent, oil dope, medicine and plasticizer Domain.It is short-chain fatty acid ester from ester type compound derived from levulic acid, boiling point is higher, being also that a class is important organises Product, can be directly used as spice, food additive, gasoline additive and biological liquid fuel etc., can be used for food, cosmetics, The industries such as medicine, plastics and transportation.
At present, preparation of the people to levulic acid expands research.But up to the present, the separation of levulic acid is reported not It is common.Document CN200510061760.4 is disclosed using resin adsorption method separating and purifying technology.The method passes through reactant liquor Weak-base ion-exchange resin post, waits not adsorbing contaminant using deionized water eluting sugar afterwards, then is adsorbed with aqueous acid eluting Levulic acid and formic acid on resin, the levulic acid for obtaining and the mixed solution of formic acid are through air-distillation and vacuum distillation Levulic acid can be obtained, yield is 85%, and purity is 98.5%.The method energy consumption is low, and selectivity is high, but can not remove oligosaccharide Deng impurity, while production capacity is not high, resin needs frequent eluting, needs a large amount of eluting solvents, and the service life of resin is not high. In addition, taking the method that organic solvent is extracted also to have research, such as methyl iso-butyl ketone (MIBK) (US2684981), n-butyl alcohol and acetic acid fourth Ester (RU2174509), sec-octyl alcohol (chemical industry and engineering, 2002,19 (2)：163-166) with aliphatic diamine (Separation and Purification Technology,200021(1-2):165-179.).But the efficiency of solvent extraction method needs to be carried Height, and there is high energy consumption in evaporation solvent.
Generally, existing levulic acid separation method separation efficiency is not high.Major reason with the system in levulic acid During standby, the impurity product such as humus and tannic acid is inevitably produced.These impurity distill or rectification in levulic acid Purification phase can further react with levulic acid, significantly reduce levulic acid yield.In addition, what existing preparation method was obtained Levulic acid mother liquid concentration relatively low (1~40%), therefore by way of traditional water evaporation reaches enriched product, there is energy Consumption is high, and yield is low, the problems such as purification high cost.
The content of the invention
Technical problem to be solved in the utility model is that prior art is present in acetyl-propionic acid compound purge process A kind of low and high energy consumption the problem of yield, there is provided separation equipment of new acetyl-propionic acid compound.The equipment has to separate imitates The characteristics of rate is high, energy consumption is low.
To solve above-mentioned technical problem, the technical scheme that the present invention takes is as follows：A kind of acetyl-propionic acid compound point From equipment, along fluid flow direction pre-filter layer, ultrafiltration layer and reverse osmosis permeable layers are at least included；Wherein, the pre-filter layer is filter Paper membrane or ceramic filtration membrane；The ultrafiltration layer is polyvinylidene fluoride film, polychloroethylene film, polysulfone membrane, Polysulfonamide, Merlon Film or polystyrene film；The reverse osmosis permeable layers are answering for cellulose acetate membrane, polyamide membrane or cellulose acetate and polyamide Close film.
In above-mentioned technical proposal, the membrane aperture of the filter paper film or ceramic filtration membrane is 0.01~150um, preferably 0.1~ 100um, more preferably 1~60um.
In above-mentioned technical proposal, further, the equipment also includes distillation column.
This utility model is easy to and levulic acid by being eliminated by membrance separation before conventional concentrating and purifying distillation column The materials such as humus, tannin and the tannic acid of the reaction of class compound, and by the further eliminating water of reverse osmosis membrane, enriched product, So as to improve the yield of levulic acid.Compared with traditional distillating method, it is to avoid in the concentration of acetyl-propionic acid compound During, the reaction of acetyl-propionic acid compound and impurity and the not high problem of caused acetyl-propionic acid compound yield make Distillation or rectification step that must subsequently be easily achieved, and reduce energy consumption, improve the economy of process, with low cost, separate The characteristics of efficiency high and easy industrialization are amplified.The acetyl-propionic acid product of yield up to 99% can be obtained using the equipment.
Description of the drawings
Fig. 1 is this utility model equipment schematic diagram.
In Fig. 1,1 is the fluid of acetyl-propionic acid compound, and 2 is pre-filter layer, and 3 is ultrafiltration layer, and 4 is reverse osmosis permeable layers, and 5 are Distillation column, 6 is the high-purity acetyl group propionic acid compounds product obtained after concentration.
Specific embodiment
Heretofore described acetyl-propionic acid compound has structure formula (I)：
In formula (I), R1For optionally substituted C1-8Straight or branched alkyl, optionally substituted C2-8Straight or branched thiazolinyl, It is preferred that optionally substituted C1-4Straight or branched alkyl, more preferably methyl；R2For hydrogen, optionally substituted C1-10Straight or branched alkane Base, preferably hydrogen, optionally substituted C1-5Straight or branched alkyl, more preferably hydrogen；N is 1~6 positive integer, preferred n is 1~ 4 positive integer, more preferably n are 2.For example, the acetyl-propionic acid compound include levulic acid, methyl ester levulinate, Ethyl levulinate, Butyl acetylpropanoate.
As one embodiment of the present invention, the fluid biomass derived material containing acetyl-propionic acid compound Hydrolyzed solution.
Used as one embodiment of the present invention, the fluid containing acetyl-propionic acid compound is derived from xylitol, Portugal At least one hydrolyzed solution in grape sugar, cellobiose, cellulose, hemicellulose and lignin；Or derived from paper mill sludge, At least one hydrolyzed solution in waste paper, bagasse, glucose, timber, corn cob, corn stalk and rice straw.
As an embodiment of the invention, to derivative described containing acetyl-propionic acid by raw material of the biological material There is no particular limitation for the method for the fluid of compound, can adopt those conventionally known in the art.For example, it is described to spread out Generation method can such as include that making the biological material carry out catalyzed conversion (such as hydrolyzes deoxidation, inorganic acid-catalyzed hydrolysis, has Machine acid-catalyzed hydrolysis, solid acid catalysis hydrolysis, molecular screen catalytic hydrolysis, supercritical hydrolysis, catalyzing part oxidation or metal chlorination Thing is catalyzed) to manufacture logistics (the particularly logistics containing levulic acid) containing acetyl-propionic acid compound the step of (such as May refer to Direct conversion of cellulose to levulinic acid and gamma- Valerolactone using solid acid catalysts, Catal.Sci.Technol., 2013,3,927-931； Production of levulinic acid and gamma-valerolactone(GVL)from cellulose using GVL as a solvent in biphasic systems, Energy Environ.Sci., 2012,5,8199-8203； Effective Production of Levulinic Acid from Biomass through Pretreatment Using Phosphoric Acid, Hydrochloric Acid, or Ionic Liquid, Ind.Eng.Chem.Res., 2014,53(29),pp 11611–11621)。
By the way that in the logistics containing acetyl-propionic acid compound that said method is obtained, the content of levulic acid is 1~40 weight Amount %.In the logistics containing acetyl-propionic acid compound, the content of water is 40~90 weight %.It is described containing acetyl-propionic acid It is 0.1~20 weight % also containing the content including humus, tannin and tannic acid impurity, these impurity in the logistics of compound. Just because of the presence of these impurity, if processing compound containing acetyl-propionic acid using conventional distillation or rectification and purification method Logistics, these impurity can further react with acetyl-propionic acid compound therein, so as to acetyl-propionic acid is greatly reduced The yield of compound.
The present invention provides a kind of separation equipment of acetyl-propionic acid compound, and along fluid flow direction pre-filtering is at least included Layer, ultrafiltration layer and reverse osmosis permeable layers；Wherein, the pre-filter layer is filter paper film or ceramic filtration membrane；The ultrafiltration layer is polyvinylidene fluoride Alkene film, polychloroethylene film, polysulfone membrane, Polysulfonamide, polycarbonate membrane or polystyrene film；The reverse osmosis permeable layers are that acetic acid is fine The composite membrane of the plain film of dimension, polyamide membrane or cellulose acetate and polyamide.
As one embodiment of the present invention, the filter paper film or ceramic filtration membrane membrane aperture be 0.01~150um, mistake Filter temperature is 0~120 DEG C, and operating pressure is 0.1~10MPa.The ceramic filtration membrane is included in aluminium oxide, titanium oxide or zirconium oxide At least one inorganic material.Fluid containing acetyl-propionic acid compound through filter paper film or ceramic filtration membrane, remove solid matter, Humus and other large granular impurities.
Used as one embodiment of the present invention, the ultrafilter membrane is selected from polyvinylidene fluoride film, polychloroethylene film, polysulfones Film, Polysulfonamide, polycarbonate membrane or polystyrene film.The ultrafilter membrane operation temperature is 1~78 DEG C, and operating pressure is 0.2~15MPa.Ultrafilter membrane can molecular cut off more than 1000 compound, for example, humus, tannin and tannic acid.
Used as one embodiment of the present invention, further, the equipment also includes reverse osmosis membrane.The reverse osmosis membrane For cellulose acetate membrane, polyamide membrane or cellulose acetate and the composite membrane of polyamide.The reverse osmosis membrane operation temperature is 5~80 DEG C, operating pressure is 2~20MPa.Reverse osmosis membrane to remove logistics in moisture.
Used as one embodiment of the present invention, the equipment also includes the distillation column after membrance separation, further to carry It is dense.There is no particular limitation for the method for the distillation, can adopt those conventionally known in the art.For example, normal pressure steams Evaporate and vacuum distillation.
As one embodiment of the present invention, when separating the fluid containing acetyl-propionic acid compound using the equipment, Comprise the following steps：A) make the logistics containing acetyl-propionic acid compound by filter paper film or ceramic filtration membrane, obtain filtrate I； The content of acetyl-propionic acid compound is 1.1~55 weight % in filtrate I；B) make filtrate I by ultrafilter membrane, obtain filtrate II； The content of acetyl-propionic acid compound is 1.1~60 weight % in filtrate II；C) make filtrate II by reverse osmosis membrane, obtain filtrate III；The content of acetyl-propionic acid compound is 70~98 weight % in filtrate II I；D) filtrate II I distillation, obtains concentration and refines Acetyl-propionic acid compound afterwards, the wherein content of acetyl-propionic acid compound are 98~99.9 weight %.
Below by embodiment, the present invention is further elaborated.
【Embodiment 1】
1.5 kilograms of corn stalks are weighed, 10 kilograms of water are placed in autoclave pressure and add, the 5mol/L of water quality 7% is added Sulfuric acid solution, at being warmed up to 180 DEG C react 45 minutes, cool down afterwards, obtain the reactant liquor containing levulic acid.Experiment is surveyed Fixed, the content of levulic acid is 31%.
6kg reactant liquors are taken by the aluminium oxide ceramics filter membrane that membrane aperture is 1um, control pressure is 1MPa, and temperature control exists 20 DEG C, collect permeate.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is Kynoar, and operating pressure is 7MPa, operation temperature is 30 DEG C, collects ultrafiltration permeate.
By ultrafiltrate through the composite membrane by cellulose acetate and polyamide, reverse osmosis concentration is filtered, and operating pressure is 10MPa, operation temperature is 25 DEG C, collects 2.4kg concentrated solutions.Afterwards the concentrated solution for obtaining is carried out into vacuum distillation, temperature 110 Levulic acid fraction is collected at DEG C.1.77kg levulic acids are collected altogether, and chromatograph detection purity is 99.5%, and yield is 95%.
【Embodiment 2】
1.1 kilograms of corn stalks are weighed, 8.6 kilograms of water are placed in autoclave pressure and add, the 5mol/L of water quality 5% is added Sulfuric acid solution, at being warmed up to 200 DEG C react 45 minutes, cool down afterwards, obtain the reactant liquor containing levulic acid.Experiment is surveyed Fixed, the content of levulic acid is 34%.
It is that 34% reactant liquor passes through titanium oxide ceramics filter membrane of the membrane aperture for 100um, control pressure to take 5kg levulic acid concentration Power is 4MPa, and temperature control collects permeate at 100 DEG C.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is polrvinyl chloride, and operating pressure is 0.5MPa, operation temperature is 25 DEG C, collects ultrafiltration permeate.
By ultrafiltrate through by polyamide membrane, reverse osmosis concentration is filtered, and operating pressure is 15MPa, and operation temperature is 80 DEG C, 1.83kg concentrated solutions are collected, afterwards the concentrated solution for obtaining is carried out into vacuum distillation, 1.63kg levulic acids are collected altogether, Chromatograph detection purity is 99.2%, and yield is 96%.
【Embodiment 3】
It is the zirconia ceramicss filter membrane of 60um by membrane aperture that the concentration for taking 6kg levulic acids is 28% reactant liquor, is controlled Pressing pressure is 8MPa, and temperature control collects permeate at 25 DEG C.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is Merlon, and operating pressure is 5MPa, operation temperature is 25 DEG C, collects ultrafiltration permeate.
By ultrafiltrate through the composite membrane by cellulose acetate and polyamide, reverse osmosis concentration is filtered, and operating pressure is 4MPa, operation temperature is 15 DEG C, collects 1.89kg concentrated solutions, afterwards the concentrated solution for obtaining is carried out into vacuum distillation, is collected altogether To 1.55kg levulic acids, chromatograph detection purity is 99.4%, and yield is 92%.
【Embodiment 4】
It is the aluminium oxide ceramics filter membrane of 0.5um by membrane aperture that the concentration for taking 5kg levulic acids is 35% reactant liquor, is controlled Pressure is 2MPa, and temperature control collects permeate at 60 DEG C.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is Merlon, and operating pressure is 4MPa, operation temperature is 30 DEG C, collects ultrafiltration permeate.
By ultrafiltrate through the composite membrane by cellulose acetate and polyamide, reverse osmosis concentration is filtered, and operating pressure is 9MPa, operation temperature is 10 DEG C, collects 1.84kg concentrated solutions, afterwards the concentrated solution for obtaining is carried out into vacuum distillation, is collected altogether To 1.72kg levulic acids, chromatograph detection purity is 99.9%, and yield is 98%.
【Embodiment 5】
It is the aluminium oxide ceramics filter membrane of 20um by membrane aperture that the concentration for taking 4kg levulic acids is 37% reactant liquor, is controlled Pressure is 0.5MPa, and temperature control collects permeate at 100 DEG C.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is Kynoar, and operating pressure is 8MPa, operation temperature is 25 DEG C, collects ultrafiltration permeate.
By ultrafiltrate through the composite membrane by cellulose acetate and polyamide, reverse osmosis concentration is filtered, and operating pressure is 10MPa, operation temperature is 25 DEG C, collects 1.72kg concentrated solutions, afterwards the concentrated solution for obtaining is carried out into vacuum distillation, is collected altogether To 1.38kg levulic acids, chromatograph detection purity is 99.4%, and yield is 93%.
【Embodiment 6】
It is the zirconia ceramicss filter membrane of 0.5um by membrane aperture that the concentration for taking 8kg levulic acids is 38% reactant liquor, is controlled Pressure is 4MPa, and temperature control collects permeate at 30 DEG C.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is polysulfones, and operating pressure is 6MPa, behaviour Make temperature for 25 DEG C, collect ultrafiltration permeate.
By ultrafiltrate through by cellulose acetate membrane, reverse osmosis concentration is filtered, and operating pressure is 8MPa, and operation temperature is 30 DEG C, 3.45kg concentrated solutions are collected, afterwards the concentrated solution for obtaining is carried out into vacuum distillation, 2.89kg levulinics are collected altogether Acid, chromatograph detection purity is 99.9%, and yield is 99%.
【Embodiment 7】
It is the aluminium oxide ceramics filter membrane of 0.01um by membrane aperture that the concentration for taking 7kg levulic acids is 36% reactant liquor, is controlled Pressing pressure is 3MPa, and temperature control collects permeate at 10 DEG C.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is Merlon, and operating pressure is 1MPa, operation temperature is 35 DEG C, collects ultrafiltration permeate.
By ultrafiltrate through the composite membrane by cellulose acetate and polyamide, reverse osmosis concentration is filtered, and operating pressure is 12MPa, operation temperature is 35 DEG C, collects 2.83kg concentrated solutions, afterwards the concentrated solution for obtaining is carried out into vacuum distillation, is collected altogether To 2.42kg levulic acids, chromatograph detection purity is 99.3%, and yield is 96%.
【Embodiment 8】
It is the zirconia ceramicss filter membrane of 40um by membrane aperture that the concentration for taking 6kg levulic acids is 34% reactant liquor, is controlled Pressure is 5.5MPa, and temperature control collects permeate at 50 DEG C.
By the permeate by throwing ultrafilter membrane of the retention more than 1000, membrane material is polysulfones, and operating pressure is 3MPa, behaviour Make temperature for 25 DEG C, collect ultrafiltration permeate.
By ultrafiltrate through by cellulose acetate membrane, reverse osmosis concentration is filtered, and operating pressure is 10MPa, operation temperature For 60 DEG C, 2.22kg concentrated solutions are collected, afterwards the concentrated solution for obtaining is carried out into vacuum distillation, 1.94kg levulinics are collected altogether Acid, chromatograph detection purity is 99.3%, and yield is 95%.

Claims (5)

1. a kind of separation equipment of acetyl-propionic acid compound, it is characterised in that at least include pre-filtering along fluid flow direction Layer, ultrafiltration layer and reverse osmosis permeable layers；Wherein, the pre-filter layer is filter paper film or ceramic filtration membrane；The ultrafiltration layer is polyvinylidene fluoride Alkene film, polychloroethylene film, polysulfone membrane, Polysulfonamide, polycarbonate membrane or polystyrene film；The reverse osmosis permeable layers are that acetic acid is fine The composite membrane of the plain film of dimension, polyamide membrane or cellulose acetate and polyamide.
2. the separation equipment of acetyl-propionic acid compound according to claim 1, it is characterised in that the filter paper film or ceramics The membrane aperture of filter membrane is 0.01~150um.
3. the separation equipment of acetyl-propionic acid compound according to claim 2, it is characterised in that the filter paper film or ceramics The membrane aperture of filter membrane is 0.1~100um.
4. the separation equipment of acetyl-propionic acid compound according to claim 3, it is characterised in that the filter paper film or ceramics The membrane aperture of filter membrane is 1~60um.
5. the separation equipment of acetyl-propionic acid compound according to claim 1, it is characterised in that further, described to set It is standby also to include distillation column.
CN201621079203.5U 2016-09-23 2016-09-23 Splitter of acetylpropionic acid class compound Active CN206168241U (en)

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