A purification device and method for bio-based succinic acid raw material and its application

Abstract

This invention belongs to the field of butanediol production, and relates to a purification device and method for bio-based succinic acid raw materials for preparing green butanediol, as well as its application. The purification device for bio-based succinic acid raw materials includes a bio-based succinic acid raw material source, a low-carbon alcohol solvent source, a mixing container, and an adsorption tower. The adsorption tower contains four layers of adsorbent, including, from top to bottom, an activated carbon layer, a macroporous polysulfonate-based styrene cation exchange resin layer, a polystyrene macroporous strong acid cation exchange resin layer, and a particulate retention material layer. This invention passes the obtained bio-based succinic acid solution into the adsorption tower containing the specific four layers of adsorbent. Through direct adsorption, succinic acid raw materials meeting the requirements for BDO production can be directly obtained from the outlet of the adsorption tower. This reduces the impact of impurities on the activity and lifespan of the esterification reaction catalyst, thus providing a raw material guarantee for obtaining BDO with the required purity.

Description

Technical Field

[0001] This invention belongs to the field of butanediol production, and relates to a purification device and method for bio-based succinic acid raw materials for preparing green butanediol, as well as its application. Background Technology

[0002] 1,4-Butanediol (BDO) is an important organic chemical raw material, mainly used in the production of tetrahydrofuran (THF), polybutylene terephthalate (PBT), γ-butyrolactone, polyurethane (PU), and the biodegradable plastic polybutylene succinate (PBS). The main processes for BDO production include the Reppe process, maleic anhydride hydrogenation process, butadiene process, propylene oxide process, and bioconversion process. Currently, the Huntsman / Davy n-butane-maleic anhydride combined process is considered a relatively advanced route for BDO production.

[0003] There are two methods for producing BDO using biological methods. The first method is direct fermentation, which involves mixing sugars with water, inorganic salts, and microorganisms. Through the fermentation process, the sugars are directly converted into BDO. However, the fermentation products still suffer from low concentration, high impurities, high separation costs, and high water consumption. In addition, biocatalysts, such as enzymes and E. coli, cannot be reused. The second method uses sugars as raw materials to produce succinic acid through fermentation. BDO is then prepared from bio-based succinic acid. This technology has been successfully used by companies such as BASF, Covestro, Toray Industries, and Lanxess in Germany to produce BDO. Compared with the petroleum-based method, it fundamentally avoids dependence on fossil fuels and significantly reduces the greenhouse effect. Compared with the direct fermentation method, it avoids many technical difficulties caused by the immaturity of the process.

[0004] Currently, the main challenge in the process of preparing BDO by further hydrogenating bio-based succinic acid (BDO) from dimethyl succinate produced by esterification with methanol via bio-based succinic acid is that the bio-based succinic acid solution contains various impurities such as ammonia nitrogen, metals, and halide ions before entering the reaction step. The ammonia nitrogen content is 0.3-0.5%, the metal content is 0.002-0.01%, and the halogen content is 0.005-0.05%, which seriously affects the catalyst activity and lifespan, and indirectly affects the quality of the final product, 1,4-butanediol. Therefore, this invention has originally developed a separation and purification technology suitable for bio-based succinic acid solutions.

[0005] For example, existing impurity removal technologies for bio-based succinic acid, such as patent application number 202211159695.9, involve obtaining succinic acid fermentation broth through biological fermentation, first filtering to obtain a filtrate, then using a specific extractant to extract succinic acid from the filtrate, followed by back-extraction with water as a back-extraction agent. The back-extraction solution containing succinic acid is then evaporated, concentrated, and crystallized. After drying the crystals, a succinic acid product with a purity >99.8% is obtained. Although this product produces a light or even colorless PBS during polymerization, meeting the quality requirements for polymerization-grade products, its drawback lies in the complex process and high energy consumption during evaporation, concentration, and crystallization. For instance, patent (patent application number 202210324856.9) uses microwave-UV synergistic technology for pretreatment of bio-based succinic acid. While the process is simple, it cannot accurately remove various impurities such as ammonia nitrogen, metals, and halide ions. All of the above-mentioned existing technologies have unavoidable shortcomings and therefore cannot become proprietary separation and purification technologies for bio-based succinic acid. Summary of the Invention

[0006] To address the technical problems existing in the prior art, this invention provides a purification device and method for preparing bio-based succinic acid raw materials for green butanediol (BDO), as well as its application. This invention mixes bio-based succinic acid raw materials that do not meet the requirements for BDO production with a solvent, and then passes the resulting bio-based succinic acid solution into an adsorption tower containing a specific four-layer adsorbent. Through direct adsorption, succinic acid raw materials meeting the requirements for BDO production can be directly obtained from the outlet of the adsorption tower. The purification process is simpler and does not require high heat consumption, making it more energy-efficient. In the above purification process, the ammonia nitrogen content in the purified bio-based succinic acid solution is ≤0.1 mg / L, and the metal ion content is ≤0. The content of 0.001 wt%, halide ion content ≤0.002 wt%, and activated carbon content ≤0.00001 wt% (based on 100 wt% of bio-based succinic acid) can reduce the impact of the above impurities on the activity and service life of the esterification reaction catalyst, thereby providing a raw material guarantee for obtaining BDO with the required purity. When methanol is used as the preferred solvent for dissolving bio-based succinic acid raw material in this invention, a purified succinic acid solution with methanol as the solvent can be directly obtained from the outlet of the adsorption tower. Both methanol and succinic acid are esterification raw materials for BDO production and can be directly applied to downstream BDO production, which further saves on the production process.

[0007] The inventors believe that the advantages of this invention are due to the following: This invention employs a four-layer adsorbent, comprising, from top to bottom, an activated carbon layer, a macroporous polysulfonate-based styrene cation exchange resin layer, a polystyrene macroporous strong acid cation exchange resin layer, and a particulate retention material layer. By sequentially arranging these four adsorbent layers, impurities are removed in sequence. Specifically, the first layer of adsorbent is activated carbon, which can remove ammonia nitrogen (0.3-0.5%) from the succinic acid solution, thus preventing it from clogging the pores of subsequent adsorbents and also avoiding its impact on the purity of the final product.

[0008] The second adsorbent is a macroporous polysulfonate-based styrene cation exchange resin layer, which removes metal ions (content of 0.002-0.01%) from the succinic acid solution, thus avoiding their influence on the catalyst activity and lifespan.

[0009] The third adsorbent is a polystyrene macroporous strong acid cation exchange resin layer, which removes halogen ions (content of 0.005-0.05%) from the succinic acid solution, mainly iodide ions and chloride ions, to avoid their presence affecting the catalyst activity and lifespan.

[0010] The fourth layer of adsorbent is a particulate-retaining material, which removes the powder particles (such as activated carbon powder) that have fallen off from the aforementioned adsorbent due to long-term continuous operation, thus avoiding the introduction of new impurities in subsequent processes.

[0011] Although the two adsorbent layers in this invention are ion exchange resins, since solvents such as methanol are organic solvents and succinic acid is also an organic compound, the dissolution of succinic acid in methanol is a case of similar solvents dissolving in each other, and does not involve ionization or hydrolysis to produce H+. + or OH - Therefore, the purification process does not affect the adsorption environment of the ion exchange resin adsorbent material, such as pH. In this way, different ion exchange resins can adsorb different impurities, making it possible for this invention to use two different ion exchange resins for impurity removal.

[0012] The purification process of this invention pertains to the adsorption of trace components. It can generally operate continuously for about a year before each layer of adsorbent reaches saturation, resulting in a long continuous operating time.

[0013] The first aspect of the present invention is to provide a purification apparatus for bio-based succinic acid raw materials, the purification apparatus comprising a bio-based succinic acid raw material source, a low-carbon alcohol solvent source, a mixing container, and an adsorption tower;

[0014] The bio-based succinic acid raw material source and the low-carbon alcohol solvent source are respectively connected to the inlet of the mixing container to obtain a bio-based succinic acid solution with low-carbon alcohol as solvent in the mixing container.

[0015] The adsorption tower has a feed inlet at the top and a discharge outlet at the bottom, and the discharge outlet of the mixing container is connected to the feed inlet of the adsorption tower.

[0016] The adsorption tower contains four layers of adsorbent, including, from top to bottom, an activated carbon layer, a macroporous polysulfonate-based styrene cation exchange resin layer, a polystyrene macroporous strong acid cation exchange resin layer, and a particulate retention material layer.

[0017] The adsorption tower is obtained by sequentially filling the four layers of adsorbent into the tower body of the adsorption tower from bottom to top. The adsorbent is protected by setting grids at the top and bottom ends of the four layers of adsorbent and between the layers of adsorbent. The above-mentioned filling of adsorbent and setting of grids are conventional operations in the art and will not be described in detail here.

[0018] According to some preferred embodiments of the present invention, the iodine value of the activated carbon in the activated carbon layer is >1500, and preferably the pressure resistance value of the activated carbon is above 0.3 MPa.

[0019] The iodine value of activated carbon is an important indicator of its adsorption performance. The iodine value refers to the number of grams of iodine that can be absorbed (added) from 100g of a substance, representing the micropore content of the activated carbon relative to the amount of iodine adsorbed from the solution. It reflects the ability of activated carbon to bind with iodine molecules and is a fundamental parameter for measuring the degree of activation and adsorption performance of activated carbon. According to the present invention, preferably, the iodine value of the activated carbon in the activated carbon layer is >1500.

[0020] According to the present invention, the activated carbon has a certain pressure resistance and can maintain the stability of its structure and performance within a certain pressure range. More preferably, the pressure resistance of the activated carbon is above 0.3 MPa.

[0021] According to some preferred embodiments of the present invention, the macroporous polysulfonate-based styrene cation exchange resin in the macroporous polysulfonate-based styrene cation exchange resin layer is selected from at least one of C100S, C160S, C150S, C100H, C160H, C150H, C150, C160, and C100, and preferably the macroporous polysulfonate-based styrene cation exchange resin has a Na content of [missing information]. + The volume exchange capacity is ≥1.8 eq / l, and the particle size distribution is 425-1200 μm, preferably C150S.

[0022] The above-mentioned macroporous polysulfonate styrene cation exchange resins are all commercially available products, such as C150S.

[0023] According to some preferred embodiments of the present invention, the polystyrene macroporous strong acid cation exchange resin in the polystyrene macroporous strong acid cation exchange resin layer is selected from at least one of SGC100X10TLH, NRW1160LS, C100X10DLH, SSTPPC60H, NRW100X10, NRW1160LI7, C100FL / 4821, C100X16MBH, CT-145Ag2244, and SSTC6000E; preferably, the polystyrene macroporous strong acid cation exchange resin is H + / Ag + The silver content is not less than 6.5 wt%, the proportion of particles with a size distribution of 500-1000 μm is more than 94 wt%, and the proportion of particles larger than 1000 μm is less than 5 wt%; more preferably, it is CT-145Ag2244.

[0024] According to the present invention, all of the above-mentioned polystyrene macroporous strong acid cation exchange resins are commercially available products, for example, CT-145Ag2244 is a brand name.

[0025] According to some preferred embodiments of the present invention, the particulate-retaining material in the particulate-retaining material layer is selected from at least one of microfiltration membrane, ultrafiltration membrane, nanofiltration membrane, reverse osmosis membrane, and molecular sieve. The above membrane materials can be, for example, ceramic membrane materials. Preferably, the particulate-retaining material layer is a molecular sieve, and more preferably, at least one of A, X, Y, M and ZSM type molecular sieves.

[0026] According to some preferred embodiments of the present invention, the volume ratio of the activated carbon layer, the macroporous polysulfonate-based styrene cation exchange resin layer, the polystyrene macroporous strong acid cation exchanger layer, and the particulate retention material layer is 1:(0.5-1.5):(0.5-1.5):(0.5-1.5), preferably 1:(0.8-1.2):(0.8-1.2):(0.8-1.2).

[0027] A second aspect of the present invention is to provide a method for purifying bio-based succinic acid raw materials using the purification equipment described in the first aspect, comprising:

[0028] Bio-based succinic acid raw material and low-carbon alcohol solvent are mixed in a mixing container to obtain a bio-based succinic acid solution with low-carbon alcohol as the solvent;

[0029] The bio-based succinic acid solution is passed through the adsorption tower for impurity removal to obtain a purified bio-based succinic acid solution.

[0030] According to some preferred embodiments of the present invention, the bio-based succinic acid raw material contains 0.3-0.5 wt% ammonia nitrogen, 0.002-0.01 wt% metal ions, and 0.005-0.05 wt% halide ions;

[0031] The detection methods for ammonia nitrogen, metal ions, and halide ions in the above-mentioned bio-based succinic acid raw materials are conventional detection methods in this field and belong to the prior art, and will not be described in detail here.

[0032] According to some preferred embodiments of the present invention, the low-carbon alcohol solvent is selected from at least one of methanol, ethanol, and propanol, preferably methanol.

[0033] According to some preferred embodiments of the present invention, the mass ratio of the low-carbon alcohol solvent to the bio-based succinic acid raw material is (5-20):1, preferably (10-20):1. Under the preferred ratio conditions, the purification and impurity removal effect is better.

[0034] According to some preferred embodiments of the present invention, the conditions for impurity removal include:

[0035] Temperature 80–120℃, and / or pressure 0.1–0.4 MPa, and / or flow rate 0.5–1.8 m / s.

[0036] According to some preferred embodiments of the present invention, the purified bio-based succinic acid solution obtained by the present invention has an ammonia nitrogen content ≤0.1mg / L, a metal ion content ≤0.001wt%, a halide ion content ≤0.002wt%, and an activated carbon content ≤0.00001wt%. Based on the mass of bio-based succinic acid as 100wt%, the above detection items can be verified by liquid chromatography characterization.

[0037] A third aspect of the present invention is to provide the application of the purification apparatus described in the first aspect and the purification method described in the second aspect in the field of BDO production.

[0038] According to some preferred embodiments of the present invention, when the low-carbon alcohol solvent is methanol, the purified bio-based succinic acid solution obtained from the purification equipment is used as a raw material for BDO production and directly applied to the production of BDO.

[0039] According to the above technical solution, this invention mixes bio-based succinic acid raw material that cannot meet the requirements for BDO production with a solvent, and then passes the resulting bio-based succinic acid solution into an adsorption tower containing a specific four-layer adsorbent. Through direct adsorption, succinic acid raw material that meets the requirements for BDO production can be directly obtained from the outlet of the adsorption tower. The purification process is simpler and does not require high heat consumption, making it more energy-efficient. In the above purification process, the purified bio-based succinic acid solution contains ≤0.1 mg / L ammonia nitrogen, ≤0.001 wt% metal ion, and ≤0.002 wt% halide ion. The activated carbon content is ≤0.00001wt% (based on 100wt% of bio-based succinic acid), which can reduce the impact of the above impurities on the activity and service life of the esterification reaction catalyst, thus providing a raw material guarantee for obtaining BDO with the required purity. When methanol is used as the preferred solvent for dissolving bio-based succinic acid raw material in this invention, a purified succinic acid solution with methanol as the solvent can be directly obtained from the outlet of the adsorption tower. Both methanol and succinic acid are esterification raw materials for BDO production and can be directly applied to downstream BDO production, which saves more on the production process.

[0040] By using the aforementioned adsorption tower containing a specific four-layer adsorbent, the ammonia nitrogen, metal, and halide ions in the bio-based succinic acid raw material are reduced to a low level, meeting the production requirements of BDO. Furthermore, the adsorbent traps particulates, preventing them from entering the purified bio-based succinic acid raw material. This reduces the impact of the aforementioned impurities on the activity and lifespan of the esterification reaction catalyst, thereby ensuring that the purity of the BDO product meets the requirements.

[0041] Compared with the existing technologies (patent application numbers 202211159695.9 and 202210324856.9) for removing impurities from bio-based succinic acid solutions, which result in incomplete impurity removal, high energy consumption, and complex processes, the purification method and equipment of this invention are simple and have fewer process steps. Compared with existing purification methods, it also has the advantages of energy saving and consumption reduction, and has extremely high value for promotion and application. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the purification equipment for bio-based succinic acid raw materials according to the present invention;

[0043] 1 is a bio-based succinic acid raw material source;

[0044] 2 is a low-carbon alcohol solvent source;

[0045] 3 is a mixing container;

[0046] 4 is the activated carbon layer;

[0047] 5 is a macroporous polysulfonate-based styrene cation exchange resin layer;

[0048] 6 is a layer of polystyrene macroporous strong acid cation exchange resin;

[0049] 7 is the particulate-retaining material layer;

[0050] 8 represents the shell of the adsorption tower. Detailed Implementation

[0051] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0052] like Figure 1 As shown, the purification equipment for bio-based succinic acid raw material of the present invention includes a bio-based succinic acid raw material source 1, a low-carbon alcohol solvent source 2, a mixing container 3, and an adsorption tower.

[0053] The bio-based succinic acid raw material source 1 and the low-carbon alcohol solvent source 2 are respectively connected to the inlet of the mixing container 3 to obtain a bio-based succinic acid solution with low-carbon alcohol as solvent in the mixing container 3.

[0054] The adsorption tower has a feed inlet at the top and a discharge outlet at the bottom, and the discharge outlet of the mixing container is connected to the feed inlet of the adsorption tower.

[0055] The adsorption tower (i.e., the adsorption tower shell 8) is provided with four layers of adsorbent, including, from top to bottom, an activated carbon layer 4, a macroporous polysulfonate-based styrene cation exchange resin layer 5, a polystyrene macroporous strong acid cation exchange resin layer 6, and a particulate retention material layer 7.

[0056] In the following embodiments, the raw material equipment in this invention is as follows:

[0057] The purification equipment has the following structure: Figure 1 As shown, the activated carbon in the activated carbon layer 4 has an iodine value of 1800 and a pressure resistance value of 0.4 MPa or higher.

[0058] The macroporous polysulfonate-based styrene cation exchange resin layer 5 is C150S, purchased from [source missing]. Its polymer backbone is a macroporous polystyrene-divinylbenzene copolymer; its morphology and appearance are spherical particles; the functional group is a sulfonic acid group; the ionic form at the factory is Na. + Volume exchange capacity (Na) + )≥1.8eq / l(39.3Kgr / ft 3 The particle size distribution is 425-1200μm; and the content of particles <425μm is ≤2wt%.

[0059] Polystyrene macroporous strong acid cation exchange resin layer 6 is CT-145Ag2244, purchased from [source missing]. Its polymer matrix is ​​macroporous polystyrene crosslinked with divinylbenzene; its appearance is spherical beads; the functional group is sulfonic acid group; the ionic form (at the time of manufacture) is hydrogen form / silver form H. + / Ag + The total capacity (in sodium ion form) is 1.4 equivalents / liter (minimum); the bead size range (micrometers) is +1000μm <5%, -500μm <1%; the silver content is at least 6.5 grams per 100 grams.

[0060] The particle trapping material layer 7 is a type A molecular sieve.

[0061] In the following examples, the bio-based succinic acid raw material contains 0.4 wt% ammonia nitrogen, 0.005 wt% metal ions, and 0.02 wt% halide ions.

[0062] In the following examples, the method for detecting the impurity content in the purified bio-based succinic acid solution is liquid chromatography.

[0063] Example 1

[0064] Purification methods for bio-based succinic acid raw materials include:

[0065] use Figure 1 The purification equipment described above, wherein the volume ratio of activated carbon layer 4, macroporous polysulfonate-based styrene cation exchange resin layer 5, polystyrene macroporous strong acid cation exchange resin layer 6, and particulate retention material layer 7 is 1:1:1:1.

[0066] The specific steps are as follows:

[0067] Bio-based succinic acid raw material and methanol are mixed in a mixing container to obtain a bio-based succinic acid solution; the mass ratio of methanol to bio-based succinic acid raw material is 15:1.

[0068] The bio-based succinic acid solution is passed into the adsorption tower for impurity removal. The impurity removal conditions include: temperature 100℃, pressure 0.2MPa, and flow rate 1m / s, to obtain a purified bio-based succinic acid solution.

[0069] The purified bio-based succinic acid solution was detected by liquid chromatography, and the results are shown in Table 1.

[0070] Example 2

[0071] The bio-based succinic acid raw material was purified according to the method of Example 1, except that the volume ratio of activated carbon layer 4, macroporous polysulfonate-based styrene cation exchange resin layer 5, polystyrene macroporous strong acid cation exchange resin layer 6 and particulate retention material layer 7 was 1:1.4:1.4:1.4.

[0072] Example 3

[0073] The bio-based succinic acid raw material was purified according to the method in Example 1, except that the mass ratio of methanol to bio-based succinic acid raw material in the bio-based succinic acid solution was 18:1.

[0074] Example 4

[0075] The bio-based succinic acid raw material was purified according to the method in Example 1, except that...

[0076] The volume ratio of activated carbon layer 4, macroporous polysulfonate-based styrene cation exchange resin layer 5, polystyrene macroporous strong acid cation exchange resin layer 6, and particulate retention material layer 7 is 1:0.5:0.5:0.5.

[0077] Example 5

[0078] The bio-based succinic acid raw material was purified according to the method in Example 1, except that the mass ratio of methanol to bio-based succinic acid raw material in the bio-based succinic acid solution was 5:1.

[0079] Comparative Example 1

[0080] The method is the same as in Example 1, except that the filling method of the adsorbent in the adsorption tower is different and the order of the adsorbent in the adsorption tower is changed. Specifically, the adsorption tower (i.e., the adsorption tower shell 8) is provided with four layers of adsorbent, which are arranged from top to bottom as follows: macroporous polysulfonate-based styrene cation exchange resin layer 5, polystyrene macroporous strong acid cation exchange resin layer 6, activated carbon layer 4, and particulate retention material layer 7; other conditions are the same as in Example 1.

[0081] Comparative Example 2

[0082] The method of Example 1 is the same, except that the filling method of the adsorbent in the adsorption tower is different. Specifically, the order of the adsorbent in the adsorption tower is changed. Specifically, the adsorption tower (i.e., the shell 8 of the adsorption tower) is provided with four layers of adsorbent, which are arranged from top to bottom as follows: activated carbon layer 4, polystyrene macroporous strong acid cation exchange resin layer 6, macroporous polysulfonate styrene cation exchange resin layer 5, and particulate retention material layer 7; other conditions are the same as in Example 1.

[0083] Comparative Example 3

[0084] The method is the same as in Example 1, except that the adsorbent filling method in the adsorption tower is different. The default adsorption tower has a particle retention material layer 7. Specifically, the adsorption tower (i.e., the adsorption tower shell 8) is provided with three layers of adsorbent, which are arranged from top to bottom as activated carbon layer 4, macroporous polysulfonate styrene cation exchange resin layer 5, and polystyrene macroporous strong acid cation exchange resin layer 6. The volume ratio of the three layers of adsorbent is 1:1:1, and other conditions are the same as in Example 1.

[0085] Table 1

[0086]

[0087] Compared to Example 1, Comparative Example 1 changed the order of the adsorbents in the adsorption tower to macroporous polysulfonated styrene cation exchange resin layer 5, polystyrene macroporous strong acid cation exchange resin layer 6, activated carbon layer 4, and particulate retention material layer 7. The content of metal impurities and halide ion impurities increased significantly, and the metal impurities and halide ions could not be effectively removed, which could not meet the application requirements of subsequent processes.

[0088] Compared to Example 1, Comparative Example 2 changed the order of the adsorbents in the adsorption tower to activated carbon layer 4, polystyrene macroporous strong acid cation exchange resin layer 6, macroporous polysulfonate styrene cation exchange resin layer 5, and particulate retention material layer 7, which significantly increased the content of halogen ion impurities.

[0089] Compared to Example 1, Comparative Example 3, which uses the default adsorbent 7 in the adsorption tower (i.e., the order of adsorbents in the adsorption tower is activated carbon layer 4, macroporous polysulfonated styrene cation exchange resin layer 5, and polystyrene macroporous strong acid cation exchange resin layer 6), shows a significant increase in the impurity content of the activated carbon.

[0090] As can be seen from the comparison of Examples 1-5 and Comparative Examples 1-3, the present invention mixes bio-based succinic acid raw materials that do not meet the requirements for BDO production with a solvent, and passes the resulting bio-based succinic acid solution into an adsorption tower containing a specific four-layer adsorbent. Through direct adsorption, succinic acid raw materials that meet the requirements for BDO production can be directly obtained from the outlet of the adsorption tower. The purification process is simpler and does not require high heat consumption, making it more energy-efficient. In the above purification process, the purified bio-based succinic acid solution has an ammonia nitrogen content ≤0.1mg / L, a metal ion content ≤0.001wt%, a halide ion content ≤0.002wt%, and an activated carbon content ≤0.00001wt% (based on the mass of bio-based succinic acid as 100wt%). This can reduce the impact of the above impurities on the activity and service life of the esterification reaction catalyst, thereby providing a raw material guarantee for obtaining BDO with the required purity, achieving unexpected technical effects.

[0091] Compared to Example 1, Example 2 changed the volume ratio of the adsorbents to 1:1.4:1.4:1.4. The amount of the latter three adsorbents increased, but the content of the four impurities remained essentially unchanged. (That is, an adsorbent volume ratio of 1:1:1:1 is sufficient to effectively remove the four impurities; preferably, the volume of the latter three adsorbents should not be further increased). Therefore, Example 1, with a volume ratio of 1:(0.8~1.2):(0.8~1.2):(0.8~1.2) for the activated carbon layer 4, macroporous polysulfonate-based styrene cation exchange resin layer 5, polystyrene macroporous strong acid cation exchange resin layer 6, and particulate retention material layer 7, has both superior technical effects and is more economical.

[0092] In Example 3, compared to Example 1, the mass ratio of methanol to bio-based succinic acid raw material was changed to 18:1. The amount of methanol increased, but the content of the four impurities remained essentially unchanged, resulting in comparable effects. Therefore, in this invention, the preferred mass ratio of low-carbon alcohol solvent to bio-based succinic acid raw material is (10-20):1. Low-carbon alcohol solvents, such as methanol, can effectively dissolve succinic acid, thereby effectively removing the four impurities. More preferably, the mass of methanol is further increased, with the mass ratio of low-carbon alcohol solvent to bio-based succinic acid raw material being (10-15):1.

[0093] In Example 4, compared to Example 1, the volume ratio of the adsorbent was changed to 1:0.5:0.5:0.5. The amounts of the latter three adsorbents were reduced to a level outside the preferred range. The content of the first impurity remained essentially unchanged, but the content of the latter three impurities increased. Therefore, compared to Example 4, Example 1, with a volume ratio of 1:(0.8~1.2):(0.8~1.2):(0.8~1.2) for the activated carbon layer 4, macroporous polysulfonate-based styrene cation exchange resin layer 5, polystyrene macroporous strong acid cation exchange resin layer 6, and particulate retention material layer 7, further exhibits superior technical effects.

[0094] In Example 5, compared to Example 1, the mass ratio of methanol to bio-based succinic acid raw material was changed to 5:1. The amount of methanol used was reduced to a level outside the preferred range, and the content of the four impurities increased. It is evident that Example 1, within the preferred mass ratio range of low-carbon alcohol solvent to bio-based succinic acid raw material of this invention, achieved further unexpected technical effects.

[0095] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

[0096] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0097] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0098] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values; such ranges or values ​​should be understood to include values ​​close to them. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In principle, various technical solutions can be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0099] In the context of this specification, except where expressly stated otherwise, any matters or issues not mentioned shall apply directly to those known in the art without any modification.

[0100] Furthermore, any implementation described herein can be freely combined with one or more other implementations described herein, and the resulting technical solutions or technical ideas shall be regarded as part of the original disclosure or original record of the present invention, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider the combination to be obviously unreasonable.

Claims

1. A purification device for bio-based succinic acid raw material, the purification device comprising a bio-based succinic acid raw material source, a low-carbon alcohol solvent source, a mixing container, and an adsorption tower; The bio-based succinic acid raw material source and the low-carbon alcohol solvent source are respectively connected to the inlet of the mixing container to obtain a bio-based succinic acid solution with low-carbon alcohol as solvent in the mixing container. The adsorption tower has a feed inlet at the top and a discharge outlet at the bottom, and the discharge outlet of the mixing container is connected to the feed inlet of the adsorption tower. in, The adsorption tower is equipped with four layers of adsorbent, including, from top to bottom, an activated carbon layer, a macroporous polysulfonate-based styrene cation exchange resin layer, a polystyrene macroporous strong acid cation exchange resin layer, and a particulate retention material layer.

2. The purification equipment according to claim 1, characterized in that: The activated carbon in the activated carbon layer has an iodine value >1500, and preferably the activated carbon has a pressure resistance value of 0.3 MPa or higher; and / or, The macroporous polysulfonate-based styrene cation exchange resin in the macroporous polysulfonate-based styrene cation exchange resin layer is selected from at least one of C100S, C160S, C150S, C100H, C160H, C150H, C150, C160, and C100, and preferably the macroporous polysulfonate-based styrene cation exchange resin has a Na content of [missing information]. + Volume exchange capacity ≥1.8 eq / l, particle size distribution 425-1200 μm.

3. The purification equipment according to claim 1, characterized in that: The polystyrene macroporous strong acid cation exchange resin in the polystyrene macroporous strong acid cation exchange resin layer is selected from at least one of SGC100X10TLH, NRW1160LS, C100X10DLH, SSTPPC60H, NRW100X10, NRW1160LI7, C100FL / 4821, C100X16MBH, CT-145Ag2244, and SSTC6000E; preferably, the polystyrene macroporous strong acid cation exchange resin is H + / Ag + The silver content is not less than 6.5 wt%, the proportion of particles with a particle size distribution of 500-1000 μm is more than 94 wt%, and the proportion of particles larger than 1000 μm is less than 5 wt%; more preferably, it is CT-145Ag2244. And / or, The particulate-retaining material in the particulate-retaining material layer is selected from at least one of microfiltration membranes, ultrafiltration membranes, nanofiltration membranes, reverse osmosis membranes, and molecular sieves, preferably molecular sieves.

4. The purification equipment according to any one of claims 1-3, characterized in that: The volume ratio of the activated carbon layer, the macroporous polysulfonate-based styrene cation exchange resin layer, the polystyrene macroporous strong acid cation exchanger layer, and the particulate retention material layer is 1:(0.5-1.5):(0.5-1.5):(0.5-1.5), preferably 1:(0.8-1.2):(0.8-1.2):(0.8-1.2).

5. A method for purifying bio-based succinic acid raw material using the purification equipment according to any one of claims 1-4, comprising: Bio-based succinic acid raw material and low-carbon alcohol solvent are mixed in a mixing container to obtain a bio-based succinic acid solution with low-carbon alcohol as the solvent; The bio-based succinic acid solution is passed through the adsorption tower for impurity removal to obtain a purified bio-based succinic acid solution.

6. The purification method according to claim 5, characterized in that: The bio-based succinic acid raw material contains 0.3–0.5 wt% ammonia nitrogen, 0.002–0.01 wt% metal ions, and 0.005–0.05 wt% halide ions; and / or, The lower alcohol solvent is selected from at least one of methanol, ethanol, and propanol, preferably methanol; and / or, The mass ratio of the low-carbon alcohol solvent to the bio-based succinic acid raw material is (5-20):1, preferably (10-20):

1.

7. The purification method according to claim 5, characterized in that: The conditions for impurity removal include: Temperature 80–120℃, and / or pressure 0.1–0.4 MPa, and / or flow rate 0.5–1.8 m / s.

8. The purification method according to any one of claims 5-7, characterized in that: The purified bio-based succinic acid solution obtained has an ammonia nitrogen content ≤0.1 mg / L, a metal ion content ≤0.001 wt%, a halide ion content ≤0.002 wt%, and an activated carbon content ≤0.00001 wt%, based on a bio-based succinic acid mass of 100 wt%.

9. The application of the purification equipment according to any one of claims 1-4 and the purification method according to any one of claims 5-8 in the field of BDO production.

10. The application according to claim 9, characterized in that: include: When methanol is used as the low-carbon alcohol solvent, the purified bio-based succinic acid solution obtained from the purification equipment is used as a raw material for butanediol production and is directly applied to the production of butanediol.

Images