Xylose extraction method
By steam blasting and enzymatic treatment of non-grain biomass, combined with ion exchange and chromatography, the problem of low xylose extraction efficiency in the prior art is solved, and high-purity and high yield xylose extraction is achieved. It is suitable for a variety of non-grain biomass and has good process stability.
Patent Information
- Application Number
- CN202510212720.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2025-04-18
AI Technical Summary
In the prior art, the efficiency of extracting xylose from non-grain biomass enzymatic solution is low, and the processing efficiency and stability are low, and the types of raw materials are limited. It is impossible to conduct in-depth research on the utilization of other non-grain biomass.
By steam blasting and enzymatic treatment of non-food biomass, the enzymatic solution is obtained, and the primary and secondary ion exchange is performed, and finally high-purity xylose is obtained by chromatography.
The efficient utilization of various non-grain biomass is achieved, and the obtained xylose is purity ≥99.9%, the yield is ≥70%, and the process is simple and stable, which extends the use cycle of production equipment and reduces production costs.
Smart Images
Figure CN119842992A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of fermentation technology, and in particular to a method for extracting xylose. Background Art
[0002] Non-food biomass mainly includes starchy cash crops such as cassava, lignocellulose (such as crop straw, forestry waste, firewood forest) and other biomass resources that are not made of food as raw materials. According to domestic and foreign research and related reports on engineering applications, non-food biomass can be processed through corresponding processes to obtain products such as glucose (C6) and xylose (C5). Glucose can be used for commercial microbial fermentation, while xylose is a high-value product because its price has been stable at 20,000-25,000 yuan / t for a long time.
[0003] The xylose extraction process is too complicated, with more than a dozen existing process methods, which greatly reduces the engineering fault tolerance rate and increases the floor space and use cost; and there are fewer types of raw materials that can be used, and the non-grain biomass currently used is mostly corn stalks. There is no in-depth research on how to extract xylose from other non-grain biomass such as reeds, sugarcane bagasse, etc., and the existing methods of using non-grain biomass for xylose extraction have low processing efficiency and stability.
[0004] Therefore, how to provide a method for extracting xylose more efficiently by using enzymatic hydrolysates of more types of non-food biomass is of great significance for the reuse of non-food biomass and the production of xylose. Summary of the invention
[0005] The main purpose of the present invention is to provide a method for extracting xylose, so as to solve the problem of low efficiency of xylose extracted from non-food biomass enzymatic hydrolysate in the prior art.
[0006] In order to achieve the above-mentioned purpose, according to the first aspect of the present invention, a method for extracting xylose is provided, which comprises: subjecting non-food biomass to steam explosion treatment and enzymatic hydrolysis treatment in sequence to obtain non-food biomass enzymatic hydrolysate; subjecting the non-food biomass enzymatic hydrolysate to primary ion exchange and secondary ion exchange in sequence to obtain a concentrated solution; and subjecting the concentrated solution to chromatography to obtain xylose.
[0007] Furthermore, the non-food biomass includes non-food biomass containing lignocellulose; preferably, the non-food biomass is selected from any one or more of the following: corn straw, reed, bagasse, wheat straw, rice straw, rape straw or cotton stalk.
[0008] Furthermore, the steam explosion includes: continuous steam explosion or instantaneous ejection steam explosion; preferably, the pressure of the continuous steam explosion is 1.0-1.6MPa; preferably, the pressure of the instantaneous ejection steam explosion is 1.0-1.4MPa; preferably, the time for continuous steam explosion is 5-10min; preferably, the time for instantaneous ejection steam explosion is 2-6min.
[0009] Furthermore, the enzyme used for the enzymatic hydrolysis treatment is hemicellulase and / or cellulase; preferably, the amount of enzyme added is 1-4% of the dry weight of the material after steam explosion treatment, calculated by mass fraction; preferably, the time of the enzymatic hydrolysis treatment is 24-96h; preferably, the temperature of the enzymatic hydrolysis treatment is 40-60°C; preferably, the pH value of the enzymatic hydrolysis treatment is 5-6.
[0010] Furthermore, the types of resins used for primary ion exchange are sodium ion resin and calcium ion resin, preferably sodium ion resin; preferably, the pH value of the primary ion exchange is 4-6; preferably, the feed amount of the primary ion exchange is 120-130 L / d.
[0011] Furthermore, the type of resin used for the secondary ion exchange is a sodium ion resin; preferably, the pH value of the secondary ion exchange is 5-6; preferably, the feed rate of the secondary ion exchange is 50-70 L / d.
[0012] Furthermore, before the primary ion exchange, the extraction method further comprises: subjecting the non-food biomass enzymatic hydrolysate to microfiltration; preferably, the diameter of the filter membrane for microfiltration is 40-70 nm.
[0013] Furthermore, after the primary ion exchange and before the secondary ion exchange, the extraction method further comprises: decolorizing the filtrate after the primary ion exchange; preferably, using a decolorizing agent to decolorize the filtrate after the primary ion exchange; more preferably, the amount of the decolorizing agent added is 3-10‰ of the filtrate after the primary ion exchange, measured by mass fraction.
[0014] Furthermore, after the secondary ion exchange and before the concentrated solution is subjected to chromatography, the extraction method further comprises monitoring the conductivity of the filtrate after the secondary ion exchange, and when the conductivity is less than 50 μs / cm, subjecting the concentrated solution to chromatography.
[0015] Furthermore, after the concentrated solution is subjected to chromatography, the extraction method further comprises: evaporating and crystallizing the xylose solution obtained after the chromatography to obtain xylose crystals, namely xylose; preferably, the flow rate of the concentrated solution during the chromatography process is 50-70 L / d.
[0016] By applying the technical scheme of the present invention, a variety of non-food biomass can be used as raw materials to prepare biomass enzymatic hydrolysate, and the xylose extracted by ion exchange and chromatography has a high purity and yield (purity ≥99.9%, xylose yield ≥70% or more), and the yield of glucose obtained is also ≥70%, which is higher than the yield results of most existing extraction technologies; and the extraction method of the present application is relatively simple, and the process stability is controllable. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:
[0018] Figure 1 A schematic diagram of the process of xylose extraction in the present application is shown. DETAILED DESCRIPTION
[0019] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0020] As mentioned in the background art, the steps of extracting xylose from non-food biomass in the prior art are relatively cumbersome, inefficient, and due to the complexity of the process, the stability of industrial production is also poor. In addition, the prior art is accustomed to using corn stalks to prepare non-food biomass enzymatic hydrolysate, and then extracting xylose, which has not been achieved to be able to utilize a wide range of non-food biomass. Therefore, the present application is to be able to utilize more types of non-food biomass and obtain xylose extracts more efficiently and stably, and proposes the method of extracting xylose from non-food biomass of the present application.
[0021] In a first typical embodiment of the present application, a method for extracting xylose is provided, which comprises: subjecting non-food biomass to steam explosion treatment and enzymatic hydrolysis treatment in sequence to obtain a non-food biomass enzymatic hydrolysate; subjecting the non-food biomass enzymatic hydrolysate to primary ion exchange and secondary ion exchange in sequence to obtain a concentrated solution; and subjecting the concentrated solution to chromatography to obtain xylose.
[0022] The present application decomposes the polysaccharides in the non-food biomass by steam explosion and enzymolysis, thereby improving the degradation and dissolution of the nutrients therein for subsequent recycling. The obtained biomass enzymolysis solution is subsequently subjected to ion exchange separation to remove a large number of ions in the solution, and C5 xylose and C6 glucose are further separated by chromatography, so that a xylose extract with high yield and purity can be obtained, and the process is relatively simple.
[0023] The xylose extraction method of the present application is applicable to any non-food biomass containing lignocellulose. In a preferred embodiment, the non-food biomass is selected from any one or more of the following: corn stalks, reeds, bagasse, wheat stalks, rice straw, rape straw or cotton stalks.
[0024] Any steam explosion method capable of releasing macromolecular substances in non-food biomass is applicable to the present application. In a preferred embodiment, the steam explosion includes: continuous steam explosion or instantaneous ejection steam explosion; preferably, the pressure of the continuous steam explosion is 1.0-1.6MPa; preferably, the pressure of the instantaneous ejection steam explosion is 1.0-1.4MPa; preferably, the time for continuous steam explosion is 5-10min; preferably, the time for instantaneous ejection steam explosion is 2-6min.
[0025] In order to further decompose the cellulose in the biomass after steam explosion decomposition into monosaccharides, in a preferred embodiment, the enzyme used for enzymatic hydrolysis is hemicellulase and / or cellulase; preferably, the amount of enzyme added is 1-4% of the dry weight of the material after steam explosion treatment in terms of mass fraction; preferably, the time of enzymatic hydrolysis is 24-96h; preferably, the temperature of enzymatic hydrolysis is 40-60°C; preferably, the pH value of enzymatic hydrolysis is 5-6.
[0026] The present invention performs ion exchange on the biomass enzymatic hydrolysate to remove ionic impurities in the enzymatic hydrolysate, thereby avoiding the prior art method of first evaporating the Cl - The higher the concentration, the more corrosive the production equipment. In order to remove more than 90% of the SO in the enzymatic hydrolyzate after the primary ion exchange, 4 2- , Ca 2+ Mg 2+ , Cl - Plasma is removed. In a preferred embodiment, the types of resins used for primary ion exchange are sodium ion resin and calcium ion resin, preferably sodium ion resin; preferably, the pH value of the primary ion exchange is 4-6; preferably, the feed amount of the primary ion exchange is 120-130L / d.
[0027] In order to further remove salt ions in the enzymatic hydrolysate, in a preferred embodiment, the type of resin used for secondary ion exchange is sodium ion resin; preferably, the pH value of the secondary ion exchange is 5-6; preferably, the feed rate of the secondary ion exchange is 50-70 L / d. After the secondary ion exchange, the conductivity of the enzymatic hydrolysate is reduced to less than 50 μs / cm.
[0028] In order to preliminarily remove larger impurities in the enzymatic hydrolysate, in a preferred embodiment, before performing primary ion exchange, the extraction method further includes: subjecting the non-food biomass enzymatic hydrolysate to microporous filtration; preferably, the diameter of the filter membrane for microporous filtration is 40-70 nm.
[0029] In order to obtain a xylose extract with higher purity, it is also necessary to remove the pigment impurities in the enzymatic hydrolyzate. In a preferred embodiment, after the primary ion exchange and before the secondary ion exchange, the extraction method further includes: decolorizing the filtrate after the primary ion exchange; preferably, using a decolorizer to decolorize the filtrate after the primary ion exchange; preferably, the amount of the decolorizer added is 3-10‰ of the filtrate after the primary ion exchange, measured by mass fraction.
[0030] When the conductivity is higher than 50μs / cm, it will affect the purity of sugars in the enzymatic hydrolyzate, and further affect the chromatographic separation efficiency. In a preferred embodiment, after the secondary ion exchange and before the concentrated solution is subjected to chromatography, the extraction method further includes monitoring the conductivity of the filtrate after the secondary ion exchange, and when the conductivity is less than 50μs / cm, the concentrated solution is subjected to chromatography.
[0031] In order to obtain a xylose extract that is easy to use or store later, in a preferred embodiment, after the concentrated solution is subjected to chromatography, the extraction method further includes: evaporating and crystallizing the xylose solution obtained after the chromatography to obtain xylose crystals, i.e., xylose; preferably, the flow rate of the concentrated solution during the chromatography process is 50-70 L / d. Among them, a flow rate that is too high will result in a shorter residence time of the enzymatic hydrolyzate in the chromatography system and inability to effectively separate; a flow rate that is too low will result in reduced separation efficiency.
[0032] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.
[0033] The non-food biomass used in this application comes from the Hubei Academy of Agricultural Sciences, the surrounding areas of the Economic Development Zone of Diaobingshan City, Tieling City, Liaoning Province, and Yiyuan Jianhua Farm in Lancang County, Pu'er City, Yunnan Province; cellulase comes from Angel Yeast Enzyme Preparation Company; hemicellulase comes from Angel Yeast Enzyme Preparation Company; sodium ion resin comes from Xi'an Lanxiao Technology; calcium ion resin comes from Xi'an Lanxiao Technology. The pore size of the first-level ion-crossing resin is 320μm, and the pore size of the second-level ion-crossing resin is 280μm, both of which are sodium ion resins.
[0034] Example 1 (using Figure 1 Prepared according to the process shown in the figure)
[0035] Preparation of biomass enzymatic hydrolysate: 1kg of 1-10cm bagasse raw material is moistened with water, the moisture content is controlled to 30%, and then transferred to a continuous steam explosion device for explosion treatment, wherein the continuous steam explosion pressure is 1.6Mpa, and it lasts for 10min. After the reaction is completed, the pressure is quickly released, and the steam-exploded slag-liquid mixture is added to an enzymatic hydrolysis reaction tank, and the steam-exploded slag-liquid mixture is prepared into a mixed liquid with a solid content of 18wt% in the reaction tank with 50°C hot water, and then 1wt% of cellulase (based on the dry matter mass of the mixed liquid) is added, the pH of the mixed liquid is adjusted to 5.0, and enzymolysis is performed at 50°C for 24h; after the enzymatic hydrolysis is completed, the enzymatically hydrolyzed material is put into a horizontal screw centrifuge, and the supernatant is taken after centrifugation and heated to 65°C, and then plate and frame filter pressing is performed to remove the insoluble matter in the sugar solution to obtain the biomass enzymatic hydrolysate.
[0036] Xylose extraction: The biomass enzymatic hydrolysate obtained above was filtered through a 40 nm microfiltration and then subjected to primary ion exchange. The resin type used was a sodium ion resin with a resin loading of 60 kg. The pH of the primary ion exchange was 4.0 and the feed flow rate was 130 L / d. More than 92% of SO in the sugar solution was removed. 4 2- , Ca 2+ Mg 2+ , Cl - Plasma, the filtrate obtained by the primary ion exchange is added with activated carbon of 6‰ of the solution mass and stirred at high temperature for decolorization. The decolorized liquid is subjected to secondary ion exchange to remove the remaining ions. The type of resin used is sodium ion resin, the loading amount of the resin is 50kg, the pH of the secondary ion exchange is 5.0, and the feed flow rate is 50L / d. When the conductivity is 23μs / cm, it enters the chromatography. The flow rate of the concentrate in the sugar separation chromatography is 50L / d. The obtained C5 is concentrated and crystallized to obtain xylose crystals, i.e. xylose, with a xylose purity of 99.9%, a xylose yield of more than 78%, and a glucose yield of 81%.
[0037] Among them, the calculation method of xylose purity is xylose concentration / dry matter concentration; the calculation method of xylose yield is the absolute dry concentration of xylose extract / absolute dry concentration of xylose in biomass enzymatic hydrolysate; the calculation method of glucose yield is the absolute dry concentration of glucose extract / absolute dry concentration of glucose in biomass enzymatic hydrolysate.
[0038] Example 2
[0039] Preparation of biomass enzymatic hydrolysate: 1kg of 1-10cm rape straw is moistened with water, the moisture content is controlled to 40%, and then transferred to the instantaneous ejection steam explosion equipment for explosion treatment, wherein the instantaneous ejection steam explosion controls the pressure to 1.2Mpa and the reaction time is 6min. After the reaction is completed, the pressure is quickly relieved, and the slag liquid mixture after steam explosion is added to the reaction tank, and the slag liquid mixture after steam explosion is prepared into a mixed liquid with a solid content of 15wt% in the reaction tank with 50℃ hot water, 4wt% of cellulase (based on the dry matter mass of the mixed liquid) is added, the pH is adjusted to 6.0, and enzymolysis is carried out at 60℃ for 48h. After the enzymolysis is completed, the material enters the horizontal screw centrifuge, and the supernatant is taken after centrifugation and heated to 65℃, and then plate and frame filter press is performed to remove the insoluble matter in the sugar solution to obtain the biomass enzymatic hydrolysate.
[0040] Xylose extraction: The biomass enzymatic hydrolysate obtained above was filtered through a 46 nm microfiltration and then entered the primary ion exchange. The resin type used was a sodium ion resin with a resin loading of 60 kg. The pH of the primary ion exchange was 5.0 and the feed flow rate was 124 L / d. More than 94% of SO in the sugar solution was removed. 4 2- , Ca 2+ Mg 2+ , Cl - Plasma, the filtrate obtained by primary ion exchange is added with activated carbon of 3‰ of the solution mass and stirred at high temperature for decolorization, and the decolorized liquid is subjected to secondary ion exchange to remove the remaining ions. The type of resin used is sodium ion resin, the loading amount of the resin is 50kg, the pH of the secondary ion exchange is 5.5, and the feed flow rate is 70L / d. When the conductivity is 45μs / cm, it enters the chromatography. The flow rate of the concentrate in the sugar separation chromatography is 60L / d. The obtained C5 is concentrated and crystallized to obtain xylose crystals, i.e. xylose, with a xylose purity of 99.9%, a xylose yield of 78%, and a glucose yield of 85%.
[0041] Example 3
[0042] Preparation of biomass enzymatic hydrolysate: 1kg of 1-10cm wheat straw is moistened with water, the moisture content is controlled to 35%, and then transferred to an instant ejection steam explosion device for explosion treatment, wherein the instant ejection steam explosion controls the pressure to 1.0Mpa and the reaction time is 4min. After the reaction is completed, the pressure is quickly released, and the slag-liquid mixture after steam explosion is added to a reaction tank, and the slag-liquid mixture after steam explosion is prepared into a mixed liquid with a solid content of 10wt% in the reaction tank with hot water, 2wt% of cellulase (based on the dry matter mass of the mixed liquid) is added, the pH is adjusted to 5.5, and enzymolysis is carried out at 40°C for 96h. After the enzymolysis is completed, the material enters a horizontal screw centrifuge, and the supernatant is taken after centrifugation and heated to 65°C, and then plate and frame filter press is performed to remove the insoluble matter in the sugar solution to obtain the biomass enzymatic hydrolysate.
[0043] Xylose extraction: The biomass enzymatic hydrolysate obtained above was filtered through a 46nm microfiltration and then entered the primary ion exchange. The resin type used was a sodium ion resin with a resin loading of 60kg. The pH of the primary ion exchange was 6.0 and the feed flow rate was 121L / d. More than 98% of SO in the sugar solution was removed. 4 2- , Ca 2+ Mg 2+ , Cl - Plasma, the filtrate obtained by the primary ion exchange is added with activated carbon of 4‰ of the solution mass and stirred at high temperature for decolorization. The decolorized liquid is subjected to secondary ion exchange to remove the remaining ions. The type of resin used is sodium ion resin, the loading amount of the resin is 50kg, the pH of the secondary ion exchange is 6.0, and the feed flow rate is 60L / d. When the conductivity is 50μs / cm, it enters the chromatography. The flow rate of the concentrated solution in the sugar separation chromatography is 62L / d. The obtained C5 is concentrated and crystallized to obtain xylose crystals, i.e. xylose, with a xylose purity of 99.9%. And the xylose yield is 81%, and the glucose yield is 83%.
[0044] Example 4
[0045] Preparation of biomass enzymatic hydrolysate: 1kg of 1-10cm cotton stalks are moistened with water, the moisture content is controlled to 35%, and then transferred to an instant ejection steam explosion device for explosion treatment, wherein the instant ejection steam explosion controls the pressure to 1.4Mpa and the reaction time is 2min. After the reaction is completed, the pressure is quickly released, and the slag-liquid mixture after steam explosion is added to a reaction tank, and the slag-liquid mixture after steam explosion is prepared into a mixed liquid with a solid content of 10wt% in the reaction tank with hot water, 2wt% of cellulase (based on the dry matter mass of the mixed liquid) is added, the pH is adjusted to 5.5, and enzymolysis is performed at 40°C for 72h. After the enzymolysis is completed, the material enters a horizontal screw centrifuge, and the supernatant is taken after centrifugation and heated to 65°C, and then plate and frame filter press is performed to remove the insoluble matter in the sugar solution to obtain the biomass enzymatic hydrolysate.
[0046] Xylose extraction: The biomass enzymatic hydrolysate obtained above was filtered through a 70nm microfiltration and then entered the primary ion exchange. The resin type used was a sodium ion resin with a resin loading of 60kg. The pH of the primary ion exchange was 4.5, and the feed flow rate was 124L / d. More than 94% of SO in the sugar solution was removed. 4 2- , Ca 2+ Mg 2+ , Cl -Plasma, the filtrate obtained by primary ion exchange is added with activated carbon with a mass of 10‰ of the solution and stirred at high temperature for decolorization. The decolorized liquid is subjected to secondary ion exchange to remove the remaining ions. The resin type used is sodium ion resin, the resin loading amount is 50kg, the pH of the secondary ion exchange is 5.5, and the feed flow rate is 60L / d. When the conductivity is 45μs / cm, it enters the chromatography. The flow rate of the concentrate in the sugar separation chromatography is 70L / d. The obtained C5 is concentrated and crystallized to obtain xylose crystals, i.e. xylose, with a xylose purity of 99.9%, a xylose yield of 75%, and a glucose yield of 80%.
[0047] Example 5
[0048] Preparation of biomass enzymatic hydrolysate: 1kg of 1-10cm reeds are moistened with water, the moisture content is controlled to 30%, and then transferred to a continuous steam explosion device for explosion treatment, wherein the continuous steam explosion pressure is 1.0Mpa, and the duration is 8min. After the reaction is completed, the pressure is quickly relieved, and the slag-liquid mixture after steam explosion is added to an enzymatic hydrolysis reaction tank, and the slag-liquid mixture after steam explosion is prepared into a mixed liquid with a solid content of 18wt% in the reaction tank with 50°C hot water, and then 1wt% of hemicellulase (based on the dry matter mass of the mixed liquid) is added, and the pH of the mixed liquid is adjusted to 5.0, and enzymolysis is performed at 50°C for 24h; the material after enzymolysis is completed enters a horizontal screw centrifuge, and the supernatant is taken after centrifugation and heated to 65°C, and then plate and frame filter press is performed to remove the insoluble matter in the sugar solution to obtain the biomass enzymatic hydrolysate.
[0049] Xylose extraction: The biomass enzymatic hydrolysate obtained above was filtered through a 40 nm microfiltration and then entered the primary ion exchange. The resin type used was a sodium ion resin with a resin loading of 60 kg. The pH of the primary ion exchange was 6.0 and the feed flow rate was 121 L / d. More than 90% of SO in the sugar solution was removed. 4 2- , Ca 2+ Mg 2+ , Cl - Plasma, the filtrate obtained by primary ion exchange is added with activated carbon of 5‰ of the solution mass and stirred at high temperature for decolorization, and the decolorized liquid is subjected to secondary ion exchange to remove the remaining ions. The type of resin used is sodium ion resin, the loading amount of the resin is 50kg, the pH of the secondary ion exchange is 5.5, and the feed flow rate is 60L / d. When the conductivity is 44μs / cm, it enters the chromatography. The flow rate of the concentrate in the sugar separation chromatography is 60L / d, and the obtained C5 is concentrated and crystallized to obtain xylose crystals, i.e. xylose, with a xylose purity of 99.9%, a xylose yield of 75%, and a glucose yield of 80%.
[0050] Comparative Example 1
[0051] Preparation of biomass enzymatic hydrolysate: 1 kg of 1-10 cm reeds are moistened with water, the moisture content is controlled to 30%, and added to an enzymatic hydrolysis reaction tank, 50°C hot water is used in the reaction tank to prepare a mixture of slag and liquid after steam explosion into a mixed solution with a solid content of 18wt%, and then 1wt% of cellulase (based on the dry matter mass of the mixed solution) is added, the pH of the mixed solution is adjusted to 5.0, and enzymolysis is performed at 50°C for 24 hours; the material after enzymatic hydrolysis enters a horizontal screw centrifuge, the supernatant is taken after centrifugation and the supernatant is heated to 65°C, and then plate and frame filter pressing is performed to remove insoluble matter in the sugar solution to obtain the biomass enzymatic hydrolysate.
[0052] Xylose extraction: The parameters in this stage were the same as those in Example 1. The obtained xylose had a purity of 77%, a xylose yield of 54%, and a glucose yield of 67%.
[0053] Comparative Example 2
[0054] Preparation of biomass enzymatic hydrolysate: The parameters in this stage were the same as those in Example 1 to prepare a biomass enzymatic hydrolysate.
[0055] Xylose extraction: The biomass enzymatic hydrolysate obtained above was filtered through a 40nm microfiltration and then passed through an ion resin for filtration to remove ions. The resin used was a sodium ion resin with a loading capacity of 60kg. The pH of the primary ion exchange was 6.0, and the feed flow rate was 2000L / d. More than 70% of SO in the sugar solution was removed. 4 2- , Ca 2+ Mg 2+ , Cl - Plasma, the filtrate obtained by ion exchange is added with activated carbon with a mass of 5‰ of the solution and stirred at high temperature for decolorization. When the conductivity of the decolorized liquid is 500μs / cm, it enters the chromatographic chromatography. The flow rate of the concentrated liquid in the sugar separation chromatography is 60L / d, and the purity of the obtained C5 xylose is 48%, and the xylose yield is 55%, and the glucose yield is 49%.
[0056] Comparative Example 3
[0057] Preparation of biomass enzymatic hydrolysate: 1 kg of 1-10 cm corn stalks are moistened with water, the moisture content is controlled to 30%, and added to an enzymatic hydrolysis reaction tank. In the reaction tank, the corn stalk mixture is prepared into a mixed solution with a solid content of 18 wt% using 50°C hot water, and then 1 wt% of cellulase (based on the dry matter mass of the mixed solution) is added, the pH of the mixed solution is adjusted to 5.0, and enzymatic hydrolysis is performed at 50°C for 24 hours; the material after enzymatic hydrolysis enters a horizontal screw centrifuge, and after centrifugation, the supernatant is taken and heated to 65°C, and then plate and frame filter pressing is performed to remove insoluble matter in the sugar solution to obtain the biomass enzymatic hydrolysate.
[0058] Xylose extraction: The biomass enzymatic hydrolysate obtained above was filtered through a 50 nm microfiltration and then passed through an ion resin for filtration to remove ions. The resin used was a sodium ion resin with a loading capacity of 60 kg. The pH of the primary ion exchange was 6.0 and the feed flow rate was 1000 L / d. SO was removed from the sugar solution. 4 2- , Ca 2+ Mg 2+ , Cl - When the conductivity is 1000μs / cm, the plasma enters the chromatographic column. The flow rate of the concentrate in the sugar separation chromatography is 60L / d, and the purity of the obtained C5 xylose is 38%, and the xylose yield is 34%, and the glucose yield is 40%.
[0059] From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects: the extraction method of the present application can be used to produce xylose by processing a variety of different non-food biomasses, and the obtained xylose has a high purity and yield (purity ≥ 99.9%, xylose yield ≥ 70% or more), wherein the moisture is below 0.02%, the ash is below 0.001%, and other ions are all below 0.001‰. In addition, the yield of glucose obtained is also ≥ 70%, which is higher than the yield results of most existing extraction technologies. Furthermore, the extraction method of the present application is relatively simple, and the process stability is controllable. At the same time, the removal of ions is relatively thorough, which can extend the service life of production equipment and reduce production costs.
[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A method for extracting xylose, characterized in that: The extraction method comprises: The non-food biomass is subjected to steam explosion treatment and enzymatic hydrolysis treatment in sequence to obtain an enzymatic hydrolyzate of the non-food biomass; The non-food biomass enzymatic hydrolysate is subjected to primary ion exchange and secondary ion exchange in sequence to obtain a concentrated solution; The concentrated solution is subjected to chromatography to obtain the xylose.
2. The extraction method according to claim 1, characterized in that The non-food biomass includes non-food biomass containing lignocellulose; Preferably, the non-food biomass is selected from any one or more of the following: corn straw, reed, bagasse, wheat straw, rice straw, rape straw or cotton stalk.
3. The extraction method according to claim 1, characterized in that The steam explosion includes: continuous steam explosion or instantaneous ejection steam explosion; Preferably, the pressure of the continuous steam explosion is 1.0-1.6 MPa; Preferably, the pressure of the instantaneous ejection steam explosion is 1.0-1.4 MPa; Preferably, the continuous steam explosion is performed for 5-10 minutes; Preferably, the instantaneous ejection steam explosion takes 2-6 minutes.
4. The extraction method according to claim 1, characterized in that The enzyme used in the enzymatic treatment is hemicellulase and / or cellulase; Preferably, the amount of enzyme added is 1-4% by mass of the dry weight of the material after the steam explosion treatment; Preferably, the enzymatic treatment time is 24-96h; Preferably, the temperature of the enzymatic hydrolysis treatment is 40-60°C; Preferably, the pH value of the enzymatic hydrolysis treatment is 5-6.
5. The extraction method according to claim 1, characterized in that The resin type for the primary ion exchange is sodium ion resin and calcium ion resin, preferably sodium ion resin; Preferably, the pH value of the primary ion exchange is 4-6; Preferably, the feed rate of the primary ion exchange is 120-130 L / d.
6. The extraction method according to claim 1, characterized in that The type of resin used for the secondary ion exchange is a sodium ion type resin; Preferably, the pH value of the secondary ion exchange is 5-6; Preferably, the feed rate of the secondary ion exchange is 50-70 L / d.
7. The extraction method according to claim 1, characterized in that Before performing the primary ion exchange, the extraction method further comprises: subjecting the non-food biomass enzymatic hydrolysate to microporous filtration; Preferably, the diameter of the filter membrane for the microfiltration is 40-70 nm.
8. The extraction method according to claim 1, characterized in that After the primary ion exchange and before the secondary ion exchange, the extraction method further comprises: decolorizing the filtrate after the primary ion exchange; Preferably, a decolorizing agent is used to decolorize the filtrate after the primary ion exchange; More preferably, the amount of the decolorizing agent added is 3-10‰ of the filtrate after the primary ion exchange, calculated by mass fraction.
9. The extraction method according to claim 1, characterized in that After the secondary ion exchange and before the concentrated solution is subjected to chromatography, the extraction method further comprises monitoring the conductivity of the filtrate after the secondary ion exchange, and when the conductivity is less than 50 μs / cm, subjecting the concentrated solution to chromatography.
10. The extraction method according to claim 1, characterized in that After the concentrated solution is subjected to chromatography, the extraction method further comprises: evaporating and crystallizing the xylose solution obtained after the chromatography to obtain xylose crystals, namely the xylose; Preferably, the flow rate of the concentrated solution during the chromatography process is 50-70 L / d.