Acid-sugar separation resin and preparation method thereof

Abstract

The present invention discloses an acid-sugar separation resin and a preparation method thereof, belonging to separation resin technology. The resin is formed by modifying sodium styrene sulfonate and a chloride ion type strong alkaline anion exchange resin, and then heating and polymerizing with an azo compound water-soluble free radical initiator. The acid-sugar separation resin provided by the present invention is an amphoteric ion exchange resin, and the functional groups contained in the resin structure: quaternary ammonium salt groups, so that the resin obtains excellent acid-sugar separation effect and improves the acid-sugar separation rate; the sulfonate groups contained can avoid the sulfuric acid tailing phenomenon, avoid the sulfuric acid tailing phenomenon to reduce the concentration of recovered sulfuric acid, thereby increasing the cost of subsequent sulfuric acid concentration.

Description

Technical Field

[0001] The invention relates to the technical field of separation resins, in particular to an acid-sugar separation resin and a preparation method thereof, and further to a resin suitable for separating high-concentration sulfuric acid and sugar and a preparation method thereof. Background Art

[0002] The production of biofuels and bio-based chemicals using agricultural straw biomass as raw materials can solve the problems of high carbon emissions and environmental pollution caused by the consumption of fossil resources. In the production process of biofuels and bio-based chemicals, the core is how to obtain fermentable sugars from the raw materials. Concentrated acid hydrolysis can obtain fermentable sugars under normal pressure and mild conditions. It has the significant advantages of low energy consumption, low toxic byproducts, and no need for cellulase input. Among them, sulfuric acid is the most commonly used. In order to reduce costs and reduce environmental load, sulfuric acid must be recycled and reused, so sulfuric acid and sugar must be separated.

[0003] Simulated moving bed chromatography separation technology is widely used in the separation of various substances. The key to this technology is the separation resin with special functions. However, there are very few studies on the separation of high-concentration sulfuric acid and sugar, and no commercial resin suitable for the separation of high-concentration sulfuric acid and sugar has been found on the market. Summary of the invention

[0004] The present invention aims to provide an acid-sugar separation resin and a preparation method thereof, which solves the problem of acid-sugar separation difficulty.

[0005] The present invention is achieved through the following technical solutions:

[0006] On one hand, the present invention provides a method for preparing an acid-sugar separation resin. The acid-sugar separation resin is prepared by modifying a chloride ion type strong alkaline anion exchange resin with sodium styrene sulfonate and then heating and polymerizing the resin with an azo compound water-soluble free radical initiator.

[0007] Furthermore, in the method for preparing the acid-sugar separation resin, the preparation of the acid-sugar separation resin comprises:

[0008] Adding a sodium styrene sulfonate solution to a chromatographic column filled with a chloride ion type strong basic anion exchange resin to modify the exchange resin, thereby obtaining a styrene sulfonic acid ion type strong basic anion exchange resin;

[0009] The obtained styrene sulfonic acid ion-type strong basic anion exchange resin is transferred, and an azo compound water-soluble free radical initiator is added, and after the initiator is dissolved, intermittent stirring is performed at room temperature for more than 2 days;

[0010] The resin solution after stirring is subjected to heating polymerization reaction to obtain the acid-sugar separation resin.

[0011] Furthermore, in the preparation method of the acid-sugar separation resin, the strong basic anion exchange resin is a resin containing a quaternary ammonium strong basic group.

[0012] Furthermore, in the method for preparing the acid-sugar separation resin, the chromatographic column filled with the chloride ion type strong alkaline anion exchange resin is preliminarily subjected to resin equilibration by alternately adding electrolyte solution and ultrapure water.

[0013] Furthermore, in the preparation method of the acid-sugar separation resin, electrolyte solution and ultrapure water are alternately added to balance the resin, comprising:

[0014] Add 0.5 mol / L to 2 mol / L electrolyte solution and ultrapure water alternately in this order until the ultrapure water completely washes out the electrolyte solution;

[0015] The electrolyte solutions added are NaCl solution, NaOH solution and HCl solution in sequence.

[0016] Furthermore, in the preparation method of the acid-sugar separation resin, the azo compound water-soluble free radical initiator includes: azobiscarboxyethyl-2-isobutylamidine hydrate, azobisisobutyronitrile, azobisisopropylimidazoline, azobisN-hydroxyisobutylamidine hydrate or azobisN,N'cyclobutylisobutylamidine hydrate.

[0017] Furthermore, in the preparation method of the acid-sugar separation resin, the heating polymerization reaction is carried out, comprising:

[0018] Heat at 70°C to 75°C for 1h to 10h, raise the temperature to 80°C to 85°C and heat for polymerization reaction for 1h to 10h.

[0019] Furthermore, in the preparation method of the acid-sugar separation resin, the acid-sugar separation resin is obtained and washed with water, then loaded into a packed column and rinsed with a NaCl solution to replace unreacted styrene sulfonate ions with chloride ions until no styrene sulfonate ions are detected.

[0020] Furthermore, in the preparation method of the acid-sugar separation resin, the molar amounts of sodium styrene sulfonate and azo compound water-soluble free radical initiator used per unit volume (L) of chloride ion type strong alkaline anion exchange resin are 3-8 mol and 0.1-0.5 mol, respectively.

[0021] Another aspect of the present invention provides an acid-sugar separation resin prepared by the preparation method of the acid-sugar separation resin.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] The acid-sugar separation resin provided by the present invention is an amphoteric ion exchange resin. The functional groups contained in the resin structure include: quaternary ammonium salt groups, which enable the resin to obtain excellent acid-sugar separation effect and improve the acid-sugar separation rate; and the sulfonate groups contained can avoid the sulfuric acid tailing phenomenon, thereby avoiding the situation in which the concentration of recovered sulfuric acid is reduced due to the sulfuric acid tailing phenomenon, thereby increasing the cost of subsequent sulfuric acid concentration. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0025] Figure 1 It is the separation chromatogram of DIAION SA10A (modified) resin in the test example of the present invention;

[0026] Figure 2 It is the separation chromatogram of DIAION SA10A resin in the test example of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with examples and drawings. The illustrative embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention. If specific conditions are not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0028] The technical solution of the present invention is:

[0029] The invention discloses a method for preparing an acid-sugar separation resin. The acid-sugar separation resin is prepared by modifying a chloride ion type strong alkaline anion exchange resin with sodium styrene sulfonate and then heating and polymerizing the resin with an azo compound water-soluble free radical initiator.

[0030] The acid-sugar separation resin provided by the present invention is an amphoteric ion exchange resin. The functional groups contained in the resin structure include: quaternary ammonium salt groups, which enable the resin to obtain excellent acid-sugar separation effect and improve the acid-sugar separation rate; and the sulfonate groups contained can avoid the sulfuric acid tailing phenomenon, thereby avoiding the situation in which the concentration of recovered sulfuric acid is reduced due to the sulfuric acid tailing phenomenon, thereby increasing the cost of subsequent sulfuric acid concentration.

[0031] Furthermore, the preparation of the acid-sugar separation resin comprises:

[0032] Adding a sodium styrene sulfonate solution to a chromatographic column filled with a chloride ion-type strongly basic anion exchange resin to modify the exchange resin, thereby obtaining a styrene sulfonic acid ion-type strongly basic anion exchange resin;

[0033] The obtained styrene sulfonic acid ion-type strong basic anion exchange resin is transferred, and an azo compound water-soluble free radical initiator is added, and after the initiator is dissolved, intermittent stirring is performed at room temperature for more than 2 days;

[0034] The resin solution after stirring is subjected to heating polymerization reaction to obtain the acid-sugar separation resin.

[0035] Furthermore, the strong basic anion exchange resin is a resin containing a quaternary ammonium strong basic group. In the present invention, in order to be more suitable for industrialization, the selected resin is an existing commercial resin, such as DIAION SA10A. Strong basic anion exchange resins containing a quaternary ammonium strong basic group on the market all meet the requirements.

[0036] Furthermore, the chromatographic column filled with chloride ion type strong basic anion exchange resin is preliminarily equilibrated by alternately adding electrolyte solution and ultrapure water.

[0037] Further, electrolyte solution and ultrapure water are alternately added to balance the resin, including:

[0038] Add 0.5 mol / L to 2 mol / L electrolyte solution and ultrapure water alternately in this order until the ultrapure water completely washes out the electrolyte solution;

[0039] The electrolyte solutions added are NaCl solution, NaOH solution and HCl solution in sequence.

[0040] The concentrations of the NaCl solution, NaOH solution and HCl solution used can be 0.5 mol / L, 0.75 mol / L, 1 mol / L, 1.25 mol / L, 1.5 mol / L, 1.75 mol / L or 2 mol / L, but are not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0041] Further, the azo compound water-soluble free radical initiator includes: azodicarboxyethyl-2-isobutylamidine hydrate, azobisisobutyronitrile, azobisisopropylimidazoline, azobisN-hydroxyisobutylamidine hydrate or azobisN,N'cyclobutylisobutylamidine hydrate. Preferably, the azo compound water-soluble free radical initiator used in the present invention is azodicarboxyethyl-2-isobutylamidine hydrate.

[0042] Further, the heating polymerization reaction is carried out, comprising:

[0043] Heating at 70°C to 75°C for 1h to 10h, specifically, the heating temperature can be 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, etc., but is not limited to the listed values, and other values ​​not listed in the range are also applicable. The heating time can be 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, etc., but is not limited to the listed values, and other values ​​not listed in the range are also applicable.

[0044] The polymerization reaction is heated at 80°C to 85°C for 1h to 10h. Specifically, the polymerization temperature can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, etc., but is not limited to the listed values. Other values ​​not listed in this range are also applicable. The time can be 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, etc., but is not limited to the listed values. Other values ​​not listed in this range are also applicable.

[0045] Further, the acid-sugar separation resin is washed with water, and then loaded into a packed column and rinsed with a NaCl solution to replace unreacted styrene sulfonate ions with chloride ions until no styrene sulfonate ions are detected. The NaCl solution used can be 0.5 mol / L, 0.75 mol / L, 1 mol / L, 1.25 mol / L, 1.5 mol / L, 1.75 mol / L or 2 mol / L, etc., but is not limited to the listed values, and other values ​​not listed in this range are also applicable.

[0046] Furthermore, the molar amounts of sodium styrene sulfonate and azo compound water-soluble free radical initiator used per unit volume (L) of chloride ion type strong basic anion exchange resin are 3-8 mol and 0.1-0.5 mol, respectively.

[0047] In order to further illustrate the present invention, an acid-sugar separation resin and a preparation method thereof provided by the present invention are described below in conjunction with examples. However, it should be understood that these examples are implemented on the premise of the technical scheme of the present invention, and detailed implementation methods and specific operating processes are given only to further illustrate the features and advantages of the present invention, rather than to limit the claims of the present invention, and the protection scope of the present invention is not limited to the following examples.

[0048] The strongly basic anion exchange resin used in the following examples of the present invention is DIAION SA10A resin purchased from Mitsubishi Chemical Corporation of Japan. DIAION SA10A is a gel-type commercial resin with excellent chemical stability, mechanical strength and adsorption capacity.

[0049] Embodiment 1:

[0050] The preparation method of an acid-sugar separation resin of the present embodiment comprises the following steps:

[0051] Step S1, resin equilibration: electrolyte solution and ultrapure water are added to a chromatographic column (500 ml) containing chloride ion type DIAION SA10A resin in sequence, in the order of 1 M NaCl, ultrapure water, 1 M NaOH, ultrapure water, 1 M HCl and ultrapure water, to carry out resin equilibration, each electrolyte solution is 5 L, and the amount of ultrapure water added is until the electrolyte solution is completely washed out.

[0052] Step S2, resin modification: add 1M sodium styrene sulfonate (2.5 L sodium styrene sulfonate) to a chloride ion type DIAION SA10A resin column (500 ml) to obtain a styrene sulfonate ion type DIAION SA10A resin, and wash with ultrapure water until no styrene sulfonate ions are detected in the effluent.

[0053] Step S3, resin excitation: 1L ultrapure water was used to transfer the styrene sulfonate ion type DIAION SA10A resin into a 2L round bottom reaction bottle. A water-soluble free radical initiator, 2,2'-AZOBIS[N-(2-CARBOXYETHYL)-2-METHYLPROPIONAMIDINE]N-HYDRATE, was added. After the initiator was dissolved, the reaction bottle was stirred intermittently at room temperature for 2 days to allow the initiator to diffuse into the resin.

[0054] The molar amounts of sodium styrene sulfonate and azo compound water-soluble free radical initiator used per unit volume (1 L) of chloride ion type strong basic anion exchange resin are 5 mol and 0.2 mol, respectively.

[0055] Step S4: Polymerization of styrene sulfonic acid: The resin mixture obtained in step S3 was stirred and heated at 72.5° C. for 3 h, and then heated at 82.5° C. for 3 h to polymerize the styrene sulfonic acid in the resin, thereby obtaining an acid-sugar separation resin.

[0056] Step S5: Post-treatment: After cooling, the acid-sugar separation resin was washed with water. Then, the resin was washed with 1M NaCl solution in a packed column to replace the unreacted styrene sulfonate ions with chloride ions. After supplying 1M NaCl for a total of 5 L, no styrene sulfonate ions were detected.

[0057] The acid-sugar separation resin prepared in this example is designated as DIAION SA10A (modified).

[0058] Test example

[0059] The DIAION SA10A (modified) resin and the DIAION SA10A resin prepared in Example 1 were respectively filled into glass chromatography columns (diameter 1.5 cm, length 30 cm, water circulation temperature control 50° C.), with a filling volume of 50.9-53.4 ml.

[0060] The filled resin was first equilibrated with 30wt% sulfuric acid and then washed with water until the pH was neutral. A total of 15 ml of simulated acid-sugar mixture (326 g / L sulfuric acid; 150 g / L glucose) was slowly added to the glass column through a peristaltic pump, and then ultrapure water was pumped in for elution. The peristaltic pump speed was 2 BV (bed volumes) / hour, and every 5 ml (0.1 BV) of the effluent was a sample to measure the concentration of sulfuric acid and glucose. The chromatogram of the separation of DIAION SA10A (modified) resin and DIAION SA10A is shown in Figure 1 and Figure 2 shown.

[0061] from Figure 1 and Figure 2 It can be seen that both DIAION SA10A (modified) resin and DIAION SA10A resin present good acid-sugar separation curves. Due to the resin's adsorption retardation of sulfuric acid, glucose flows out of the chromatographic column first, followed by sulfuric acid, and the two show a clear separation trend. The two resins present similar glucose distribution curves, but the distribution curves of sulfuric acid are significantly different: Figure 1 The maximum concentration of sulfuric acid in the effluent was as high as 252 g / L, and the acid-sugar separation effect was obvious; Figure 2 The maximum sulfuric acid concentration in the effluent is less than 200g / L, which is lower than that of DIAION SA10A (modified) resin, and the acid-sugar separation effect is poor. In addition, it can be clearly seen that Figure 1 The sulfuric acid tailing phenomenon disappears. Figure 2 The sulfuric acid tailing phenomenon occurs.

[0062] Embodiment 2:

[0063] The preparation method of an acid-sugar separation resin of the present embodiment comprises the following steps:

[0064] Step S1, resin equilibration: electrolyte solution and ultrapure water were added to a chromatographic column (500 ml) containing chloride ion type DIAION SA10A resin in sequence, in the order of 0.5 M NaCl, ultrapure water, 0.5 M NaOH, ultrapure water, 0.5 M HCl and ultrapure water, to carry out resin equilibration, each electrolyte solution was 5 L, and the amount of ultrapure water added was until the electrolyte solution was completely washed out.

[0065] Step S2, resin modification: add 2.5 L of 1M sodium styrene sulfonate to a chloride ion type DIAION SA10A resin column (500 ml) to obtain a styrene sulfonate ion type DIAION SA10A resin, and wash with ultrapure water until no styrene sulfonate ions are detected in the effluent.

[0066] Step S3, resin excitation: 1L ultrapure water was used to transfer the styrene sulfonate ion type DIAION SA10A resin into a 2L round bottom reaction bottle. A water-soluble free radical initiator, 2,2'-AZOBIS[N-(2-CARBOXYETHYL)-2-METHYLPROPIONAMIDINE]N-HYDRATE, was added. After the initiator was dissolved, the reaction bottle was stirred intermittently at room temperature for 2 days to allow the initiator to diffuse into the resin.

[0067] The molar amounts of sodium styrene sulfonate and azo compound water-soluble free radical initiator used per unit volume (1 L) of chloride ion type strong basic anion exchange resin are 3 mol and 0.1 mol, respectively.

[0068] Step S4: Styrene sulfonic acid polymerization: The resin mixture obtained in step S3 was stirred while being heated at 70° C. for 10 h, and then heated at 80° C. for 10 h to polymerize the styrene sulfonic acid in the resin, thereby obtaining an acid-sugar separation resin.

[0069] Step S5: Post-treatment: After cooling, the obtained acid-sugar separation resin was washed with water. Then, the resin was washed with 0.5M NaCl solution in a packed column to replace the unreacted styrene sulfonate ions with chloride ions. After supplying 0.5M NaCl for a total of 10L, no styrene sulfonate ions were detected.

[0070] Embodiment 3:

[0071] The preparation method of an acid-sugar separation resin of the present embodiment comprises the following steps:

[0072] Step S1, resin equilibration: electrolyte solution and ultrapure water were added to a chromatographic column (500 ml) containing DIAION SA10A in sequence, in the order of 2 M NaCl, ultrapure water, 2 M NaOH, ultrapure water, 2 M HCl and ultrapure water, to carry out resin equilibration, each electrolyte solution was 5 L, and the amount of ultrapure water added was until the electrolyte solution was completely washed out.

[0073] Step S2, resin modification: add 2.5 L of 1M sodium styrene sulfonate to a chloride ion type DIAION SA10A resin column (500 ml) to obtain a styrene sulfonate ion type DIAION SA10A resin, and wash with ultrapure water until no styrene sulfonate ions are detected in the effluent.

[0074] Step S3, resin excitation: 1L ultrapure water was used to transfer the styrene sulfonate ion type DIAION SA10A resin into a 2L round bottom reaction bottle. A water-soluble free radical initiator, 2,2'-AZOBIS[N-(2-CARBOXYETHYL)-2-METHYLPROPIONAMIDINE]N-HYDRATE, was added. After the initiator was dissolved, the reaction bottle was stirred intermittently at room temperature for 2 days to allow the initiator to diffuse into the resin.

[0075] The molar amounts of sodium styrene sulfonate and azo compound water-soluble free radical initiator used per unit volume (1 L) of chloride ion type strong alkaline anion exchange resin are 8 mol and 0.5 mol, respectively.

[0076] Step S4: Polymerization of styrene sulfonic acid: The resin mixture obtained in step S3 was stirred while being heated at 75° C. for 1 h, and then heated at 85° C. for 1 h to polymerize the styrene sulfonic acid in the resin, thereby obtaining an acid-sugar separation resin.

[0077] Step S5: Post-treatment: After cooling, the obtained acid-sugar separation resin was washed with water. Then, the resin was washed with 2M NaCl solution in a packed column to replace the unreacted styrene sulfonate ions with chloride ions. After supplying 2M NaCl for a total of 5 L, no styrene sulfonate ions were detected.

[0078] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing an acid-sugar separation resin, characterized in that: The acid-sugar separation resin is prepared by modifying a chloride ion type strong alkaline anion exchange resin with sodium styrene sulfonate and then heating and polymerizing with an azo compound water-soluble free radical initiator; The strong basic anion exchange resin is a resin containing a quaternary ammonium strong basic group.

2. The method for preparing the acid-sugar separation resin according to claim 1, wherein The preparation of the acid-sugar separation resin comprises: Adding a sodium styrene sulfonate solution to a chromatographic column filled with a chloride ion type strong basic anion exchange resin to modify the exchange resin, thereby obtaining a styrene sulfonic acid ion type strong basic anion exchange resin; The obtained styrene sulfonic acid ion-type strong basic anion exchange resin is transferred, and an azo compound water-soluble free radical initiator is added, and after the initiator is dissolved, intermittent stirring is performed at room temperature for more than 2 days; The resin solution after stirring is subjected to heating polymerization reaction to obtain the acid-sugar separation resin.

3. The method for preparing the acid-sugar separation resin according to claim 1 or 2, characterized in that, The chromatographic column filled with chloride ion type strong basic anion exchange resin is preliminarily equilibrated by alternately adding electrolyte solution and ultrapure water.

4. The method for preparing the acid-sugar separation resin according to claim 3, characterized in that: Alternately add electrolyte solution and ultrapure water to equilibrate the resin, including: Add 0.5mol / L~2mol / L electrolyte solution and ultrapure water alternately in this order until the ultrapure water completely washes out the electrolyte solution; The electrolyte solutions added are NaCl solution, NaOH solution and HCl solution in sequence.

5. The method for preparing the acid-sugar separation resin according to claim 1 or 2, characterized in that: The azo compound water-soluble free radical initiator includes: azobiscarboxyethyl-2-isobutylamidine hydrate, azobisisobutyronitrile, azobisisopropylimidazoline, azobisN-hydroxyisobutylamidine hydrate or azobisN,N'cyclobutylisobutylamidine hydrate.

6. The method for preparing the acid-sugar separation resin according to claim 1 or 2, characterized in that: The thermal polymerization reaction is carried out, comprising: Heat at 70℃~75℃ for 1h~10h, then heat to 80℃~85℃ and carry out polymerization reaction for 1h~10h.

7. The method for preparing the acid-sugar separation resin according to claim 1 or 2, characterized in that: The acid-sugar separation resin is obtained and washed with water, then loaded into a packed column and rinsed with a NaCl solution to replace unreacted styrene sulfonate ions with chloride ions until no styrene sulfonate ions are detected.

8. The method for preparing the acid-sugar separation resin according to claim 1 or 2, characterized in that: The molar amounts of sodium styrene sulfonate and azo compound water-soluble free radical initiator used per unit volume of chloride ion type strong alkaline anion exchange resin are 3-8 mol and 0.1-0.5 mol, respectively.

9. An acid-sugar separation resin, characterized in that The acid-sugar separation resin is prepared by the preparation method of the acid-sugar separation resin according to any one of claims 1 to 8.

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