Production process for preparing C4 saturated polyol by hydrogenation of C4 dibasic acid and / or ester thereof

Abstract

The invention provides a production process for preparing C4 saturated polyol by hydrogenation of C4 dibasic acid and / or ester thereof, which adopts a slurry bed or / and fixed bed one-section to three-section series hydrogenation reaction process and a multifunctional hydrogenation catalyst. According to the method, maleic acid, fumaric acid, succinic acid, butynedioic acid, methylmalonic acid or methylene malonic acid and esters thereof or substituted acids thereof and unsaturated bonds or / and carboxyl groups or / and ester groups in ester molecules thereof are subjected to efficient hydrogenation to prepare 1, 4-butanediol or 2-methyl-1, 3-propylene glycol or substituted polyols thereof. According to the production process disclosed by the invention, the C4 saturated polyols such as BDO and the like are generated in one step through efficient hydrogenation of the C4 dibasic acid and / or the ester thereof, the process flow is simplified, the material consumption and the energy consumption are reduced, the production cost can be further greatly reduced, and the technology has universality and can be used for producing series C4 saturated polyols.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical intermediates, and particularly relates to a production process for preparing C 4 saturated polyols by hydrogenating C 4 dicarboxylic acids and / or their esters. Background Art

[0002] C 4 Saturated polyols, including 1,4-butanediol and 2-methyl-1,3-propanediol, and their substituted polyols such as trimethylolmethane, 1,2,4-butanetriol, 1,2,3,4-butanetetraol, 2-chloro-1,4-butanediol or 2,2,3,3-tetrafluoro-1,4-butanediol, etc., are all important organic chemical and fine chemical raw materials, with wide application fields and great development potential.

[0003] For example, 1,2,4-butanetriol is a raw material for the production of drugs such as ezetimibe and rosuvastatin, and its nitrate ester is a high-quality rocket fuel. 1,2,3,4-butanetetraol (erythritol) is a low-calorie sweetener and humectant, widely used in the fields of medicine and health care, cosmetics and personal care, and food, beverage and feed, etc. 2-methyl-1,3-propanediol (MPO) is a diol with a unique methyl-branched structure. It has low volatility and good solubility at room temperature, and has the characteristics of low melting point, low toxicity, high boiling point and colorless transparency, making the polyester products prepared from it have low viscosity, low melting point, low temperature resistance, weather resistance, chemical resistance, bending resistance, tensile resistance, non-crystallinity, flexibility, and good stability and high strength. It is an ideal raw material for the production of unsaturated polyester resins, saturated polyester resins, polyester polyols, and coil coating resins; MPO has a variety of industrial applications, such as as a solvent, wetting agent and plasticizer, and can be used to manufacture unsaturated polyesters, liquid saturated polyesters, thermoplastic polyester resins (PET and PBT modification), alkyd resins, polyurethane resins, diester plasticizers, lubricants, etc., as raw materials for inks, insulating paints, cosmetics, flavors, etc., and is also used in industries such as coatings, pesticides, fungicides, and pharmaceuticals.

[0004] 1,4-Butanediol (BDO), as an important organic chemical raw material and polyester monomer, is widely used in fields such as medicine, chemical industry, textile, paper-making, automotive, and daily chemical industry. From BDO, polybutylene terephthalate (PBT), polybutylene succinate (PBS), tetrahydrofuran (THF), γ-butyrolactone (GBL), polyurethane (PU), coatings, plasticizers, etc. can be produced, and it can also be used as a solvent and a brightening agent in the electroplating industry. BDO is the basic raw material for producing PBT engineering plastics and PBT fibers; it is also the main monomer for producing a series of biodegradable plastics such as PBS, poly(butylene succinate-co-adipate) (PBSA), poly(butylene succinate-co-terephthalate) (PBST), and poly(butylene adipate-co-terephthalate) (PBAT); it is also the main raw material for producing THF. THF is an important organic solvent, and the resulting polytetramethylene glycol (PTMEG) after polymerization is the basic raw material for producing highly elastic spandex (Lycra fiber), block polyurethane, or the soft segment of block polyether polyester. In addition, pyrrolidone and N-methylpyrrolidone (NMP) produced from the downstream product GBL of BDO are polar aprotic solvents with strong selectivity and good stability, and are widely used as extractants for aromatics, olefins, and acetylene, solvents for lubricating oil refining and syngas desulfurization, polymerization solvents for poorly soluble engineering plastics (such as polyphenylene sulfide, polyimide, polyvinylidene fluoride), and aramid fibers, cleaning agents for lithium-ion batteries, insulating materials, integrated circuits, and circuit boards, and cleaning agents for deoiling, degreasing, dewaxing, polishing, rust prevention, and paint stripping; a series of high-value-added products derived from pyrrolidone such as N-vinylpyrrolidone (NVP) and polyvinylpyrrolidone (PVP) are widely used in fields such as pesticides, medicine, coatings, and cosmetics.

[0005] Currently, MPO is a by-product of the production of BDO by the hydroformylation of allyl alcohol obtained by the isomerization of propylene oxide. There are many production methods for BDO, including the Reppe process (condensing acetylene with formaldehyde to form butynediol, and then butynediol is obtained by two-step hydrogenation via butenediol), the butadiene process (butadiene acetoxylation process: obtained by hydrogenation and hydrolysis of diacetoxylated butene produced by the acetoxylation reaction of butadiene; butadiene chlorination process: obtained by hydrolysis and hydrogenation of 1,4-dichlorobutene produced by the chlorination of butadiene), the allyl alcohol process, and the maleic anhydride process, etc. Among them, in the allyl alcohol process, allyl alcohol is first prepared by the isomerization of propylene oxide or the hydrolysis of allyl acetate, and then the 4-hydroxybutyraldehyde obtained by the hydroformylation of allyl alcohol and the by-produced 2-hydroxymethyl propionaldehyde are hydrogenated to obtain BDO and by-produced MPO at the same time. For the preparation of BDO using maleic anhydride as the raw material, there are mainly three process routes: maleic anhydride hydrolysis hydrogenation method, maleic anhydride esterification hydrogenation method, and maleic anhydride direct hydrogenation method.

[0006] Preparation of BDO and MPO by hydroformylation of allyl alcohol: US Leander Chemical Patent CN104302609B discloses an improved method for the hydroformylation rate and selectivity of allyl alcohol. In a reaction kettle under a pressure of 35 - 50 psi, in the presence of a catalyst system of rhodium complex and ligand trans-1,2-bis[bis(3,5-di-n-alkylphenyl)phosphinomethyl]cyclobutane, allyl alcohol reacts with CO / H 2 to occur, with the selectivity of BDO greater than 86.6% and the selectivity of MPO greater than 12.05%, and the n / i ratio greater than 7.19. When 2,3-O-isopropylidene-2,3-dihydroxy-1,4-bis[bis(3,5-di-n-alkylphenyl)phosphinomethyl]cyclobutane is used as the ligand, the equivalent yield of BDO is increased to more than 98.65%; CN113874382B describes a highly linear selective ligand for the hydroformylation of allyl alcohol, which is trans-1,2-bis(bis(3,4,5-tri-n-alkylphenyl)phosphinomethyl)cyclobutane, and preferably the n-alkyl group is methyl and ethyl; the solvent used is selected from C 5 -C 20 aliphatic hydrocarbons, C 6 -C 12 aromatic hydrocarbons, ethers, alcohols and their mixtures, preferably toluene, cyclohexane, methylcyclohexane, methyl tert-butyl ether and their mixtures; CN111801312B discloses a method for producing BDO by hydroformylation of allyl alcohol prepared from glycerol, including the hydroformylation products of 4-hydroxybutyraldehyde (HBA) and 3-hydroxy-2-methylpropionaldehyde (HMPA) produced by the hydroformylation of allyl alcohol derived from glycerol with syngas, and BDO and MPO products produced by hydrogenating at least a part of the hydroformylation products. The hydroformylation is carried out in an anhydrous toluene solution containing a rhodium catalyst Rh(CO) 2 (acac) and a phosphine ligand. The molar ratio of Rh(CO) 2 (acac) to the diphosphine ligand is 0.1:1 - 1:5, the pressure is 20 - 600 psig, the temperature is 35 - 120 °C, and the syngas composition CO / H 2 = 0.5:1.5 - 1.5:0.5. The by-products include n-propanol, propionaldehyde and their compositions, and the total amount of by-products ≤ 0.5 mol%. Wanhua Chemical Patent CN113996347A discloses a hydroformylation catalyst composition and a method for preparing hydroxybutyraldehyde by the hydroformylation reaction of allyl alcohol. The catalyst composition includes a solvent and a complex formed in the solvent, which contains a first ligand (monophosphine), a second ligand (diphosphine) and a metal active component. The metal active component is rhodium, and the first ligand is a composition of one or more in monophosphine ligands.

[0007] Preparation of BDO by hydrolysis and hydrogenation of maleic anhydride: Maleic anhydride is first hydrogenated in aqueous phase or maleic acid is hydrogenated to obtain succinic acid, and then succinic acid is hydrogenated in aqueous phase to prepare BDO. Patent CN111689845B reported a method for the one-step aqueous-phase hydrogenation of maleic anhydride to produce succinic acid, with a maleic anhydride conversion rate > 99.6% and a succinic acid selectivity > 99.8%; a fixed-bed reactor is used, the reactor inlet temperature is 30 - 100 °C, the reactor outlet temperature is 50 - 200 °C, the reaction pressure is 0.5 - 5.0 MPa, and the mass space velocity is 0.1 - 10 h -1 , and the hydrogen-oil volume ratio is 50 - 1000; the catalyst used is Ni, Cu, Co, Mo, W, Cr, Ru, Rh, Pd, Pt, Au, Ag, B, Al, Ga, P, Bi and other metals supported on an acid-resistant carrier, and the mass percentage content of the active component is 0.3 - 30%. The acid-resistant carrier is one of activated carbon, α-alumina, silica or silicon carbide. CN109453763A discloses a Ru / SiO 2 -TiO 2 catalyst (the mass contents of Ru, SiO 2 and TiO 2 are 10 - 30%, 40 - 70% and 10 - 40% respectively). Using an aqueous succinic acid solution with a mass concentration of 10 - 30% as the raw material in an autoclave, the hydrogenation reaction is carried out at a pressure of 4 - 6 MPa and a temperature of 150 - 250 °C for 2 - 4 h, with a succinic acid conversion rate > 96% and a BDO selectivity > 90%.

[0008] Preparation of BDO by esterification and hydrogenation of maleic anhydride: First, maleic anhydride reacts with a lower monohydric alcohol (mostly C 1 - C 4 alkanol) to form a maleic acid diester, and then the maleic acid diester is hydrogenated in multiple steps to obtain BDO, and GBL and THF are co-produced. CN110563933B and CN113512183A disclose a method for preparing BDO by two-step esterification and three-step hydrogenation of maleic anhydride: Maleic anhydride is successively subjected to monoesterification to form maleic acid monoester, diesterification to form maleic acid diester, hydrogenation of maleic acid diester to form succinic acid diester, and two-step hydrogenation of succinic acid diester to prepare BDO and co-produce GBL and THF. CN112694602B reported a method for preparing BDO by three-step hydrogenation and one-step esterification of maleic anhydride: Maleic anhydride is hydrogenated to form succinic anhydride, succinic anhydride is esterified with methanol to form dimethyl succinate (DMS), DMS is hydrogenated to form GBL, and GBL is hydrogenated to form BDO and co-produce THF. CN103946201B provides a method for producing BDO by two-stage tandem hydrogenation of dialkyl maleate in a mixed liquid / gas phase, and an adiabatic fixed-bed reactor is used in both cases. In the first stage, a Pd / C or Pd / Al 2 O 3 catalyst is used, and the liquid hourly space velocity of the feed liquid is 0.5 - 2.0 h -1At a temperature of 80 - 130 °C, a hydrogen / ester molar ratio of 30 - 60, and a system pressure of 30 - 80 bar, dialkyl maleate is hydrogenated to produce dialkyl succinate, with a conversion rate of dimethyl maleate (DMM) of 100% and a selectivity of DMS of ~99%; in the second stage, a copper chromite or copper-zinc oxide catalyst containing 2 - 15 wt% BaO or MnO 2 is used, and at a feed space velocity of 0.1 - 0.3 h -1 and a temperature of 160 - 190 °C, a hydrogen / ester molar ratio of 30 - 60, and a pressure of 30 - 80 bar, dialkyl succinate is hydrogenated to produce BDO and by-products GBL and THF, with a conversion rate of DMS of 97.6 - 97.8%, a selectivity of BDO of 77.0 - 84.0%, a selectivity of THF of 6.3 - 13.1%, and a selectivity of GBL of 4.8 - 5.3%, and the total selectivity of the three is 95.0 - 95.6%.

[0009] Direct hydrogenation of maleic anhydride to prepare BDO: Generally, maleic anhydride is first hydrogenated to GBL, and then GBL is hydrogenated to BDO, with the co-production or by-production of succinic anhydride and THF. CN114181038B provides a method for producing BDO by hydrogenating maleic anhydride with the co-production of succinic anhydride. Maleic anhydride is used as a raw material to obtain BDO through two-step hydrogenation. In the first step, maleic anhydride is hydrogenated to produce GBL, succinic anhydride, THF, and water. In the second step, GBL is hydrogenated to produce BDO, and at the same time, a small amount of THF, n-butanol, and acetal are generated; both steps of hydrogenation use Cu-Ni-Al 2 O 3 / SiO 2 catalyst. In the first step, the molar ratio of hydrogen to maleic anhydride in the feed is 20 - 200, the reaction temperature is 200 - 300 °C, the reaction pressure is 0.1 - 1.0 MPa, and the mass space velocity of maleic anhydride is 0.05 - 1.00; in the second step, the molar ratio of hydrogen to GBL in the feed is 20 - 300, the reaction temperature is controlled at 120 - 200 °C, the reaction pressure is controlled at 2 - 8 MPa, and the mass space velocity of GBL is 0.05 - 2.00. CN114920913B discloses a method for preparing BDO by two-step hydrogenation of maleic anhydride. The THF solution of maleic anhydride is hydrogenated to produce succinic anhydride and GBL, and the THF solution of GBL is further hydrogenated to obtain BDO. CN114656331A provides a method for producing BDO with high yield by three-step hydrogenation of maleic anhydride. The GBL solution of maleic anhydride is hydrogenated to produce succinic anhydride, and an Al 2 O 3 loaded with one or more of 10 - 45 wt% Cu, Co, Mo, Ni, W, Ag, Pd, Pt, or Ru is used 2 or ZrO 2 or SiO -1Under the condition, the conversion rate of maleic anhydride is 100%, and the selectivity of succinic anhydride is greater than 97%; the GBL solution of succinic anhydride is hydrogenated to produce GBL and a small amount of THF, using ZrO 2 or SiO 2 catalyst loaded with one or more of Co, Mo, Ni, W, Ag, Pd, Pt or Ru at 20-55 wt%, at a molar ratio of hydrogen to succinic anhydride of 2-3:1, a GBL recycle molar ratio of 3-10:1, a reaction temperature of 130-140 °C, a reaction pressure of 4-5 MPa and a succinic anhydride space velocity of 0.3-0.7 h -1 Under the condition, the conversion rate of succinic anhydride is 76-82%, the selectivity of GBL is 99.1-99.4%, and the selectivity of THF is 0.6-0.9%; the hydrogenation of GBL produces BDO and THF, using a Cu-Zn-Al-M-O catalyst (M is one or two of Cr, Mn, Co, Mo, Ni or W) with an active metal content of 45-75 wt%, at a molar ratio of hydrogen to GBL of 150-350:1, a reaction temperature of 170-200 °C, a reaction pressure of 5-6 MPa, and a GBL space velocity of 0.2-0.3 h -1 Under the condition, the conversion rate of GBL is 92-95%, the selectivity of BDO is 94.3-95.9%, and the selectivity of THF is 3.9-5.1%.

[0010] In summary, C 4 Saturated polyols, especially MPO and BDO, have wide applications and broad development prospects. However, MPO is only a by-product of the hydroformylation of allyl alcohol to produce BDO, and both the alkynal method and the butadiene method for producing BDO have high energy consumption and serious environmental pollution. Existing process technologies for preparing BDO by hydrogenation starting from maleic anhydride: whether it is the two-step aqueous-phase hydrogenation process of maleic anhydride via succinic acid, the esterification and two-step hydrogenation process via DMM and DMS, or the two-step or three-step hydrogenation process via GBL, the reaction selectivity for preparing BDO is relatively low, and a large amount of GBL and THF are produced as by-products, resulting in a long process flow for producing BDO, high consumption of maleic anhydride raw materials, and high energy consumption in the process. Therefore, developing new raw material routes, new process technologies and high-performance catalysts to efficiently hydrogenate C 4 dicarboxylic acid esters to prepare the corresponding C 4 saturated polyols is of practical significance for reducing the production cost of C 4 saturated polyols such as BDO. Summary of the Invention

[0011] In view of this, the present invention provides a production process for hydrogenating C 4 dicarboxylic acids and / or their esters to prepare C 4 saturated polyols.

[0012] To achieve the above object, the technical solution of the present invention is specifically as follows:

[0013] A kind of C 4 Production process of preparing C-saturated polyhydric alcohol by hydrogenation of dicarboxylic acid and / or its ester, wherein the raw material C 4 Dicarboxylic acid and / or its ester are subjected to catalytic hydrogenation reaction in the presence of a multifunctional hydrogenation catalyst to prepare C 4 Saturated polyhydric alcohol. The hydrogenation reaction adopts a one-stage or two-stage series or three-stage series hydrogenation reaction process, and the hydrogenation reactor used for the hydrogenation reaction is a slurry bed reactor or / and a fixed bed reactor; wherein, 4 When the hydrogenation reaction adopts a one-stage hydrogenation reaction material external circulation process, the process includes the following operation flow: hydrogen and C

[0014] Dicarboxylic acid and / or its ester solution are mixed and preheated to 120-180 °C, and then sent into a slurry bed or fixed bed reactor filled with a pre-reduced and activated catalyst together with the recycled material for catalytic hydrogenation reaction; the hydrogenation reaction process conditions are: the concentration of the raw material C 4 Dicarboxylic acid and / or its ester solution is 10-100 wt%, the total feed weight hourly space velocity (new material + recycled material) is 0.10-1.50 h 4 -1, the liquid-phase hydrogenation material circulation ratio is 0-5.0, the reaction temperature is 150-250 °C, the system pressure is 3.0-8.0 MPa, and the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 20-200; or, -1 When the hydrogenation reaction adopts a two-stage series hydrogenation reaction process, the process includes the following operation flow: hydrogen and C

[0015] Dicarboxylic acid and / or its ester solution are mixed and preheated to 120-180 °C, and first sent into the first-stage slurry bed or fixed bed filled with a pre-reduced and activated catalyst for hydrogenation reaction, and then the first-stage hydrogenation material is sent into the second-stage slurry bed or fixed bed filled with a pre-reduced and activated catalyst in series for continuous hydrogenation reaction. The hydrogenation catalysts in the first stage and the second stage are the same or different. The two-stage series reactor is a reactor containing two beds in the first stage and the second stage or two reactors in series; the hydrogenation reaction process conditions are: the same feed space velocity and system pressure are adopted in the two-stage hydrogenation reaction, and the feed C 4 Dicarboxylic acid and / or its ester solution concentration is 10-100 wt%, the feed weight hourly space velocity is 0.10-1.00 h 4 -1, the system pressure is 3.0-8.0 MPa, the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 20-200, the reaction temperature in the first stage is 150-230 °C, and the reaction temperature in the second stage is 170-260 °C; or, -1 When the hydrogenation reaction adopts a three-stage series hydrogenation reaction process, the process includes the following operation flow: hydrogen and C

[0016] When the hydrogenation reaction adopts a three-stage series hydrogenation reaction process, its process includes the following operation flow: The three-stage series hydrogenation reaction process includes the following operation flow: Mix hydrogen and C 4 dicarboxylic acid and / or its ester solution, preheat to 120 - 180 °C, and then send them successively into a slurry bed or fixed bed filled with pre-reduced and activated catalyst in series for three-stage hydrogenation reaction. The catalysts for the three-stage reactions can be the same or different. The three-stage series reactor is one reactor containing three beds, namely the first bed, the second bed, and the third bed, or three reactors in series; The hydrogenation reaction process conditions are: The same feed space velocity and system pressure are adopted for all three-stage hydrogenation reactions. The concentration of the feed C 4 dicarboxylic acid and / or its ester solution is 10 - 100 wt%, the weight hourly space velocity of the feed is 0.15 - 1.50 h -1 , the system pressure is 3.0 - 8.0 MPa, the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 20 - 200, the reaction temperature of the first stage is 150 - 220 °C, the reaction temperature of the second stage is 170 - 240 °C, and the reaction temperature of the third stage is 190 - 260 °C.

[0017] The production process provided by the present invention is to hydrogenate and saturate the C = C bond or C≡C bond in the C 4 dicarboxylic acid and its ester molecules and hydrogenate the carboxyl group or / and ester group to hydroxyl group to prepare C 4 saturated polyol.

[0018] The present invention is further configured such that when the hydrogenation reaction adopts a one-stage hydrogenation reaction material external circulation process, the hydrogenation reaction process conditions are: The concentration of the raw material C 4 dicarboxylic acid and / or its ester solution is 15 - 75 wt%, the total feed weight hourly space velocity (new material + recycled material) is 0.20 - 1.00 h -1 , the liquid-phase hydrogenation material circulation ratio is 0 - 2.5, the reaction temperature is 160 - 230 °C, the system pressure is 4.0 - 7.0 MPa, and the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 35 - 150;

[0019] Preferably, the hydrogenation reaction process conditions are: The concentration of the raw material C 4 dicarboxylic acid and / or its ester solution is 20 - 50 wt%, the total feed weight hourly space velocity is 0.40 - 0.75 h -1 , the liquid-phase hydrogenation material circulation ratio is 0.5 - 2.0, the reaction temperature is 170 - 210 °C, the system pressure is 4.5 - 6.5 MPa, and the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 50 - 100.

[0020] In the above production process, the hydrogenation reaction material external circulation process is a reaction process in which part of the material obtained from the hydrogenation reaction is recycled back to the reactor. On the one hand, the unreacted raw material C 4The dibasic acid and its ester, as well as intermediate products such as γ-butyrolactone, are further hydrogenated to produce the target product C 4 Saturated dihydric alcohols are obtained to improve the conversion rate of raw materials and the selectivity of products. On the other hand, the externally circulated material can dilute the raw materials and remove the reaction heat, acting as a diluent and a heat removal agent, preventing excessive heat accumulation in the bed layer and temperature runaway, thereby avoiding the occurrence of side reactions such as deep hydrogenation, dehydration, and polymerization of the target product, as well as avoiding sintering deactivation of the catalyst, achieving the purpose of improving the selectivity of the target product and extending the service life of the catalyst, and at the same time reducing the use of hydrogen circulation equipment and energy consumption. The circulation ratio refers to the ratio of the amount of the material obtained from the hydrogenation reaction that is circulated back to the reactor to the amount output to the subsequent system

[0021] The present invention is further configured such that when the hydrogenation reaction adopts a two-stage series hydrogenation reaction process, the hydrogenation reaction process conditions are: feed C 4 The concentration of the dibasic acid and / or its ester solution is 25-80 wt%, the weight hourly space velocity of the feed is 0.20-0.75 h -1 -1, the system pressure is 4.0-7.0 MPa, the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 35-150, the reaction temperature of the first stage is 160-210 °C, and the reaction temperature of the second stage is 180-240 °C

[0022] Preferably, the hydrogenation reaction process conditions are: feed C 4 The concentration of the dibasic acid and / or its ester solution is 40-60 wt%, the weight hourly space velocity of the feed is 0.30-0.60 h -1 -1, the system pressure is 4.5-6.5 MPa, the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 50-100, the reaction temperature of the first stage is 170-190 °C, and the reaction temperature of the second stage is 190-220 °C

[0023] The present invention is further configured such that when the hydrogenation reaction adopts a three-stage series hydrogenation reaction process, the hydrogenation reaction process conditions are: feed C 4 The concentration of the dibasic acid and / or its ester solution is 25-90 wt%, the weight hourly space velocity of the feed is 0.20-1.00 h -1 -1, the system pressure is 4.0-7.0 MPa, the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 35-150, the reaction temperature of the first stage is 160-210 °C, the reaction temperature of the second stage is 180-230 °C, and the reaction temperature of the third stage is 200-250 °C

[0024] Preferably, the hydrogenation reaction process conditions are: feed C 4 The concentration of the dibasic acid and / or its ester solution is 40-80 wt%, the weight hourly space velocity of the feed is 0.30-0.75 h -1, system pressure 4.5 - 6.5 MPa, molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) 50 - 100, reaction temperature of the first stage 170 - 200 °C, reaction temperature of the second stage 190 - 220 °C, reaction temperature of the third stage 210 - 240 °C.

[0025] The present invention is further configured such that the slurry bed reactor is selected from a fully - mixed external - circulation cooling heat - exchange slurry bed reactor or a fully - mixed jacket - medium heat - transfer slurry bed reactor; the fixed - bed reactor is selected from a plug - flow inter - stage quenching heat - exchange adiabatic fixed - bed reactor or a plug - flow shell - and - tube medium - heat - transfer isothermal fixed - bed reactor.

[0026] The present invention is further configured such that the C 4 solvent of the binary acid and / or its ester solution is selected from 1,4 - butanediol, C 4 saturated alcohol of the corresponding by - product of the hydrogenation of the binary acid ester, tetrahydrofuran or water.

[0027] The present invention is further configured such that the multifunctional hydrogenation catalyst includes: a dual - active component composed of a noble metal and a non - noble metal, a dual - support composed of a high - specific - surface - area porous material and a high - thermal - conductivity material, and a metal - oxide structural promoter and an electronic promoter; wherein, the noble metal is selected from at least one of Ru, Os, Rh, Ir, Pd or Pt, the non - noble metal is selected from at least one of Cr, Mn, Fe, Co, Ni or Cu; the metal - oxide structural promoter is at least one of oxides of Ga, In, Sn, Nb, Mo, W, Re, Al, Ti, Zr or Zn, the electronic promoter is selected from at least one of alkaline - earth or rare - earth metal oxides, the high - specific - surface - area porous material is selected from at least one of alumina, silica, titanium oxide, zirconium oxide, zeolite molecular sieve or clay, and the high - thermal - conductivity material is selected from α - Al 2 O 3 、Si、α - SiO 2 、SiC、Mo 2 C or at least one of BN.

[0028] The present invention is further configured such that in the composition of the multifunctional hydrogenation catalyst, the noble metal is selected from one or two of Ru, Pd or Pt, the non - noble metal is selected from one or two of Mn, Ni or Cu, the metal - oxide structural promoter is selected from at least one of oxides of Ga, In, Sn, Mo, W, Re, Al, Ti, Zr or Zn, the electronic promoter is selected from one or two of oxides of Sc, Y, Mg, Ba, La or Ce, and the high - specific - surface - area porous material is selected from γ - Al 2 O 3 、mesoporous alumina, SiO 2 、mesoporous silica, TiO 2 、ZrO 2, one or two of MCM-41, MCM-48, SBA-15, hydroxyapatite (HAP) or diatomite, and the high thermal conductivity material is selected from α-Al 2 O 3 , Si, α-SiO 2 or SiC.

[0029] The present invention is further configured such that in the multifunctional hydrogenation catalyst, the proportion of the non-precious metal component is 35-60 wt%, the proportion of the precious metal component is 0.1-7.5 wt%, the proportion of the structural assistant is 5.0-35.0 wt%, the proportion of the electronic assistant is 1.0-7.5 wt%, the proportion of the high specific surface area support is 10-30 wt%, and the proportion of the high thermal conductivity support is 2.0-15.0 wt%;

[0030] Preferably, the proportion of the non-precious metal component is 40-55 wt%, the proportion of the precious metal component is 0.5-5.5 wt%, the proportion of the structural assistant is 10-30 wt%, the proportion of the electronic assistant is 2.0-5.0 wt%, the proportion of the high specific surface area support is 15-25 wt%, and the proportion of the high thermal conductivity support is 5.0-10.0 wt%.

[0031] The present invention is further configured such that the metal oxide structural assistant includes a first structural assistant and a second structural assistant, the first structural assistant is selected from at least one of Al, Ti, Zr or Zn, and the second structural assistant is selected from at least one of Ga, In, Sn, Re.

[0032] The present invention is further configured such that the precious metal is selected from one or two of Ru, Pd or Pt, and the content is 0.5-5.0 wt%; the non-precious metal is selected from Cu or a combination of Cu and Mn or Ni, and the content is 40-55 wt%, wherein the content of Cu accounts for 40-50 wt% of the total mass of the catalyst; the first structural assistant is selected from one or two of Al, Ti, Zr or Zn, and the content is 10-25 wt%; the second structural assistant is selected from Re or Sn, and the content is 1.0-5.0 wt%.

[0033] The present invention is further configured such that the multifunctional catalyst is prepared by a deposition precipitation - equal volume impregnation method, and includes the following steps:

[0034] A1. According to the metering ratio, add the high specific surface area pore material and the high thermal conductivity material into a ball mill, ball mill and screen to obtain a composite carrier powder with a particle size of 100-250 nm;

[0035] A2. According to the metering ratio, respectively prepare an aqueous solution of the precursor compound of the non-precious metal active component and the electronic assistant, and an aqueous solution or an alcohol solution of the precursor compound of the structural assistant;

[0036] A3. According to the stoichiometric ratio, add the composite carrier powder prepared in step A1 into the synthesis kettle. While stirring, simultaneously add the aqueous solution of the precursor compound of the non-noble metal active component, the aqueous solution of the precursor compound of the electronic promoter, and the aqueous solution of the precursor compound of the first structural promoter prepared in step A2 into the synthesis kettle. Adjust the pH value to 8.0 - 9.0, and then carry out steaming and aging at 75 - 85 °C for 1.0 - 3.0 h;

[0037] A4. Filter the material in step A3, wash it with water until the pH is 7.0 - 8.0, dry it at 120 - 150 °C, then crush the cake, and then calcine it in an air stream at 300 - 350 °C for 3 - 5 h and at 550 - 650 °C for 5 - 8 h to obtain a supported non-noble metal powder catalyst prepared by the deposition-precipitation method;

[0038] A5. Add 5.0 - 10.0 wt% of binder sesbania powder or methyl cellulose to the powder catalyst prepared in step A4, moisten it with water, and then form it into clover-shaped particles with a diameter of 1.6 - 3.0 mm and a length of 2 - 5 mm or cylindrical particles with a diameter of 1.6 - 3.0 mm and a length of 2 - 3 mm by extrusion or tabletting. Then calcine it in an air stream at 300 - 350 °C for 2 - 3 h and at 500 - 600 °C for 3 - 5 h to obtain a supported non-noble metal particle catalyst;

[0039] A6. According to the stoichiometric ratio, prepare an aqueous solution of the precursor compound of the second structural promoter, and impregnate the supported non-noble metal powder catalyst prepared in step A4 or the supported non-noble metal particle catalyst prepared in step A5 with it for 0.5 - 2.0 h by equal volume. Then dry it at 120 - 150 °C for 1.0 - 3.0 h, and then calcine it in an air stream at 300 - 350 °C for 1.0 - 3.0 h and at 500 - 550 °C for 3.0 - 5.0 h to obtain a non-noble metal powder catalyst or particle catalyst supported with a structural promoter respectively;

[0040] A7. According to the stoichiometric ratio, prepare a dilute hydrochloric acid aqueous solution of the precursor compound of the noble metal active component, and impregnate the non-noble metal powder catalyst or particle catalyst supported with a structural promoter prepared in step A6 with it for 0.5 - 2.0 h by equal volume. Then dry it at 120 - 150 °C for 1.0 - 3.0 h, and then calcine it in an air stream at 300 - 350 °C for 1.0 - 3.0 h and at 550 - 600 °C for 3.0 - 5.0 h to obtain a finished powder hydrogenation catalyst or a finished particle hydrogenation catalyst containing noble metal and non-noble metal active components respectively.

[0041] The present invention is further configured such that the noble metal precursor compound is one or more selected from ruthenium trichloride, osmium trichloride, rhodium trichloride, iridic acid, palladium dichloride or chloroplatinic acid; the non-noble metal precursor compound is one or more selected from chromium nitrate, manganese acetate, iron nitrate, cobalt nitrate, nickel nitrate or copper nitrate; the structure promoter precursor compound is one or more selected from gallium nitrate, indium nitrate, stannous dichloride, niobium oxalate, ammonium paramolybdate, ammonium tungstate, rhenium heptoxide, aluminum nitrate, tetrabutyl titanate, zirconium nitrate or zinc acetate; the precursor compound of the electronic promoter is at least one selected from nitrates of alkaline earth or rare earth elements.

[0042] The present invention is further configured such that the prepared finished powder catalyst or finished particle catalyst needs to be activated before the hydrogenation reaction; wherein, when the slurry bed reaction process is selected for the hydrogenation reaction process, the prepared finished powder hydrogenation catalyst is loaded into a tubular furnace, and hydrogen is introduced for programmed temperature rise and pressure reduction reduction activation of the catalyst until no more water is generated, and the activated hydrogenation catalyst is transferred to a slurry bed reactor for catalytic hydrogenation reaction; when the fixed bed reaction process is selected for the hydrogenation reaction process, the prepared finished particle hydrogenation catalyst in step A7 is loaded into a fixed bed reactor, and hydrogen is introduced for in-situ programmed temperature rise and pressure reduction reduction activation of the catalyst until no more water is generated, and the catalyst activation is completed for subsequent hydrogenation reaction;

[0043] Among them, the reduction activation conditions of the hydrogenation catalyst are: temperature 150 - 450 °C, hydrogen gas volume space velocity 10 - 200 h -1 , hydrogen pressure 0.5 - 6.0 MPa; preferably temperature 180 - 430 °C, hydrogen gas volume space velocity 30 - 150 h -1 , hydrogen pressure 1.0 - 5.5 MPa; more preferably temperature 210 - 410 °C, hydrogen gas volume space velocity 50 - 100 h -1 , hydrogen pressure 1.5 - 5.0 MPa.

[0044] The present invention is further configured such that the C 4 dicarboxylic acid and / or its ester includes maleic acid, fumaric acid, succinic acid, acetylenedicarboxylic acid, methylmalonic acid, methylenemalonic acid or / and their substituted dicarboxylic acids, and esters of these dicarboxylic acids with fatty alcohols, alicyclic alcohols, aromatic alcohols or heterocyclic alcohols.

[0045] Preferably, the C 4 dicarboxylic acid and / or its ester includes maleic acid, fumaric acid, succinic acid, acetylenedicarboxylic acid, methylmalonic acid, methylenemalonic acid, 2-hydroxymethylmalonic acid, malic acid, tartaric acid, 2-mercaptosuccinic acid, 2,3-dimercaptosuccinic acid, 2-chlorosuccinic acid, 2,3-dichlorosuccinic acid, 2-fluorosuccinic acid, 2,2-difluorosuccinic acid or tetrafluorosuccinic acid, and esters of these dicarboxylic acids with monohydric or dihydric C1 ~C 8 fatty alcohol, C 5 ~C 9 alicyclic alcohol, C 7 ~C 9 aromatic alcohol or C 3 ~C 7 monoester, diester or / and polyester of heterocyclic alcohol.

[0046] More preferably, the C 4 dicarboxylic acid and / or its ester include maleic acid, fumaric acid, succinic acid, acetylenedicarboxylic acid, methylmalonic acid, methylenemalonic acid, 2-hydroxymethylmalonic acid, malic acid, tartaric acid, 2-chlorosuccinic acid or tetrafluorosuccinic acid, and mono- or / and diesters of these dicarboxylic acids with methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, pentanol, isopentanol, neopentanol, hexanol, heptanol, octanol, isooctanol, or allyl alcohol, methallyl alcohol, crotyl alcohol, isopentenol, propargyl alcohol, butynol, or cyclopentanol, cyclohexanol, 4-methylcyclohexanol, cyclohexylmethanol, cyclohexylpropanol, or 2-chloroethanol, 3-chloropropanol, 4-chlorobutanol, 2,2,2-trifluoroethanol, or benzyl alcohol, α-phenethyl alcohol, β-phenethyl alcohol, α-methylphenethyl alcohol, hydrocinnamyl alcohol, cinnamyl alcohol, or glycidol, tetrahydrofurfuryl alcohol, furfuryl alcohol, nicotinyl alcohol, 2-pyridinemethanol, 4-piperidinemethanol or 2-thiophenemethanol, and monoester, diester or / and polyester with ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, 1,2-propanediol, dipropylene glycol, polypropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 1,4-butenediol, 1,4-butynediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, o-phthalyl alcohol, m-phthalyl alcohol, p-phthalyl alcohol, 2,5-furandimethanol or 2,6-pyridinedimethanol.

[0047] The present invention is further configured such that the C 4 saturated polyhydric alcohol includes 1,4-butanediol or 2-methyl-1,3-propanediol or their substituted polyhydric alcohols; preferably, the C 4The saturated polyols include 1,4-butanediol, 2-methyl-1,3-propanediol, 2-hydroxymethyl-1,3-propanediol (trimethylolmethane), 1,2,4-butanetriol, 1,2,3,4-butanetetrol, 2-mercapto-1,4-butanediol, 2,3-dimercapto-1,4-butanediol, 2-chloro-1,4-butanediol, 2,3-dichloro-1,4-butanediol, 2-fluoro-1,4-butanediol, 2,2-difluoro-1,4-butanediol or 2,2,3,3-tetrafluoro-1,4-butanediol; more preferably, the C 4 The saturated polyol is 1,4-butanediol, 2-methyl-1,3-propanediol, trimethylolmethane, 1,2,4-butanetriol, 1,2,3,4-butanetetrol, 2-chloro-1,4-butanediol or 2,2,3,3-tetrafluoro-1,4-butanediol.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] (1) The present invention provides C 4 Preparation of C by Hydrogenation of Dibasic Acids and Their Esters 4 The new process technology for saturated polyols adopts one to three-stage series reaction process, and a fully mixed flow slurry bed reactor (external circulation cooling heat exchange or jacket medium heat transfer) or / and adiabatic fixed bed or isothermal fixed bed reactor with rapid cooling heat exchange between plug flow stages or shell-and-tube medium heat transfer, to efficiently remove the reaction heat, and control the conversion rate and hydrogenation depth by controlling the reaction temperature and the actual amount of materials involved in the reaction (the one-stage reaction process adopts a partial material circulation strategy; the two-stage or three-stage reaction process adopts a strategy of lower temperature and high load in the first stage, higher temperature and lower load in the second stage, or higher temperature and lower load in the third stage), to achieve C 4 Highly active and selective hydrogenation of dibasic acids and their esters into C 4 Saturated polyols.

[0050] (2) The present invention provides C 4 A novel method for preparing BDO or MPO or their substituted polyols by direct hydrogenation of dibasic acids and their esters, by using a multi-component multifunctional catalyst and simultaneously 4 The unsaturated bonds in the dibasic acid and its ester molecules are hydrogenated to saturate and the carboxyl group and / or ester group are hydrogenated to hydroxyl groups, and the corresponding C 4 Saturated polyols. The prior art uses multiple catalysts and multi-step reactions, which require each step to hydrogenate and saturate unsaturated bonds, hydrogenate one carboxyl group or ester group to a hydroxyl group, and then hydrogenate another carboxyl group or ester group to a hydroxyl group. In the process, a large amount of cyclic byproducts γ-butyrolactone and tetrahydrofuran are generated, and the yield of the target product is low.

[0051] (3) The present invention provides C 4 Preparation of C by Hydrogenation of Dibasic Acids and Their Esters 4High-efficiency catalyst for saturated polyols and its preparation method. By simultaneously introducing pore materials and heat-conducting materials, especially introducing mesoporous materials with high specific surface area and new materials with high thermal conductivity as composite carriers, and adopting a method combining deposition precipitation and incipient wetness impregnation, a new multi-component and multi-functional catalyst with excellent performance containing noble metal and non-noble metal active components, structural promoters and electronic promoters, and double carriers is prepared.

[0052] (4) By adopting the above new method, new catalyst and new process technology, the present invention realizes the efficient hydrogenation of C 4 dicarboxylic acid and its esters to directly produce C 4 saturated polyols such as BDO in one step, simplifies the process flow, saves equipment investment, reduces material and energy consumption, and thus can greatly reduce the production cost and improve the market competitiveness of C 4 saturated polyol products. In addition, the technology provided by the present invention has generality and universality, and a series of C 4 saturated polyols can be produced by using this technology. Detailed implementation manners

[0053] The following further describes the present invention in conjunction with specific embodiments. It should be noted that the embodiments described in this part are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0054] Symbol and calculation description:

[0055] Abbreviations of substance names: TFSA is tetrafluorosuccinic acid, MMS is monomethyl succinate, MBM is monobutyl maleate, MBF is monobutyl fumarate, MOM is monoisooctyl maleate, MCF is monocyclohexyl fumarate, MPS is monobenzyl succinate; DMM is dimethyl maleate, DEM is diethyl maleate, DBM is dibutyl maleate, DAM is diallyl maleate, DEF is diethyl fumarate, DAF is diallyl fumarate, DMS is dimethyl succinate, DOS is diisooctyl succinate, DCS is dicyclohexyl succinate, DMAD is dimethyl acetylenedicarboxylate, DMMP is dimethyl methylmalonate, DMMM is dimethyl methylenemalonate, DMHB is dimethyl malate, DET is diethyl tartrate; MBS is monobutylene glycol monosuccinate, DBS is dibutylene glycol disuccinate, BDS is dibutylene glycol bis(monosuccinate), DXM is dibutylene glycol dimaleate, MQM is monobutyne glycol monomaleate; MPO is 2-methyl-1,3-propanediol, BDO is 1,4-butanediol, GBL is γ-butyrolactone, THF is tetrahydrofuran.

[0056] Abbreviations of reaction process names: P1 is the first-stage reaction process, P2 is the second-stage reaction process, and P3 is the third-stage reaction process; CSR is a continuous stirred tank reactor with external circulation cooling and heat exchange, JSR is a continuous stirred tank reactor with jacket medium heat removal, AFR is a plug flow adiabatic fixed bed reactor with inter-stage quenching and heat exchange, and IFR is a plug flow isothermal fixed bed reactor with shell-and-tube medium heat removal.

[0057] Reaction material circulation ratio = Circulation amount of liquid-phase material obtained in the reaction ÷ Output amount of liquid-phase material obtained in the reaction;

[0058] H 2 / Group molar ratio = Amount of hydrogen in moles ÷ (Amount of moles of the sum of unsaturated bonds, carboxyl groups, and ester groups in the dicarboxylic acid and its ester molecules); 4

[0059] Raw material C 4 Conversion rate of dicarboxylic acid and its ester = (Feed amount of dicarboxylic acid and its ester - Residual amount of dicarboxylic acid and its ester in the product) ÷ Feed amount of dicarboxylic acid and its ester × 100%; 4 4 4

[0060] Target product C 4 Selectivity of polyol = Amount of moles of polyol in the product ÷ (Feed molar amount of dicarboxylic acid and its ester - Residual molar amount of dicarboxylic acid and its ester in the product) × 100%. 4 4 4

[0061] Examples 1 - 10

[0062] Prepare the catalyst according to the catalyst composition and content shown in Table 1. The specific steps are as follows:

[0063] A1. Add high specific surface area carriers γ-Al 2 O 3 , MA (mesoporous alumina), SiO 2 , MS (mesoporous silica) or SBA-15 powder and high thermal conductivity carriers Si or SiC powder into a ball mill in proportion. After ball milling and sieving, obtain composite carriers γ-Al 2 O 3 -Si, MA-SiC, MS-Si, SiO 2 -SiC or SBA-15-Si powder with a particle size of 100 - 200 nm;

[0064] A2. Prepare aqueous solutions of non-noble metal active component precursors such as manganese acetate, nickel nitrate or copper nitrate, and aqueous solutions of electron promoter precursor compounds such as barium nitrate or cerium nitrate, and aqueous solutions of the first structural promoter precursor compounds such as aluminum nitrate, zirconium nitrate or zinc acetate, or alcoholic solutions of tetrabutyl titanate;

[0065] A3. Add the composite support γ-Al 2 O 3 -Si, MA-SiC, MS-Si, SiO 2 -SiC or SBA-15-Si powder into the synthesis kettle. While stirring, simultaneously add the aqueous solution of the non-noble metal active component precursor compound, the aqueous solution of the electron promoter precursor compound, and the aqueous solution of the first structural promoter precursor compound prepared in step A2 into the synthesis kettle. Adjust the pH to about 8.5 with dilute nitric acid or sodium carbonate aqueous solution, and then steam-cook and age at 80 °C for 2.0 h;

[0066] A4. Filter the material in step A3, wash it with softened water until the pH is about 8.0, dry it at 120 °C, then crush the cake, and then calcine it in an air stream at 350 °C for 3 h and at 600 °C for 5.0 h to obtain the supported non-noble metal powder catalyst CuZnAlBa / γ-Al 2 O 3 -Si, CuZnNiCe / MA-SiC, CuZnMnCe / MS-Si, CuZnTiCe / SiO 2 -SiC or CuZnZrCe / SBA-15-Si prepared by the deposition-precipitation method;

[0067] A5. Add 8.0 wt% of the binder methyl cellulose to the supported non-noble metal powder catalyst prepared in step A4, moisten it with water and extrude it into clover-shaped particles with a diameter of 2.2 mm and a length of 3 - 5 mm, and then calcine it in an air stream at 350 °C for 2.0 h and at 600 °C for 5.0 h to obtain the supported non-noble metal particle catalyst CuZnAlBa / γ-Al 2 O 3 -Si, CuZnNiCe / MA-SiC, CuZnMnCe / MS-Si, CuZnTiCe / SiO 2 -SiC or CuZnZrCe / SBA-15-Si;

[0068] A6. Prepare an aqueous solution of the second structural promoter precursor compound, tin dichloride or rhenium heptoxide, in proportion, and impregnate the supported non-noble metal powder catalyst prepared in step A4 or the supported non-noble metal particle catalyst prepared in step A5 with it for 1.0 h in an equal volume, then dry at 150 °C for 2.0 h, and then calcine in an air stream at 300 °C for 1.0 h and at 500 °C for 3.0 h to obtain the supported promoter non-noble metal powder catalyst or particle catalyst respectively;

[0069] A7. Prepare a dilute hydrochloric acid aqueous solution of the noble metal active component precursor compound, ruthenium trichloride, palladium dichloride or chloroplatinic acid, in proportion, and impregnate the supported promoter non-noble metal powder catalyst or particle catalyst prepared in step A6 with it for 2.0 h in an equal volume, then dry at 120 °C for 2.0 h, and then calcine in an air stream at 350 °C for 3.0 h and at 600 °C for 5.0 h to obtain the finished powder catalyst or finished particle catalyst containing noble metal and non-noble metal active components PtSn-CuZnAlBa / γ-Al 2 O 3 -Si, PdRe-CuZnNiCe / MA-SiC, PtRuSn-CuZnMnCe / MS-Si, PtRe-CuZnTiCe / SiO 2 -SiC or RuRe-CuZnZrCe / SBA-15-Si.

[0070] The mass percentage contents and their numbers of the catalysts, each component and the carrier prepared above are listed in Table 1. The catalysts in Table 1 have not been reduced and activated yet. The noble metal component content is the content percentage of the metal, and the non-noble metal components are all the content percentages of their oxides:

[0071] Table 1C 4 Catalysts for hydrogenation of dibasic acids and their esters to C 4 Saturated polyhydric alcohols and their numbers

[0072]

[0073]

[0074] Before using the catalysts Cat-1 to Cat-10, the prepared multifunctional catalyst needs to be activated. The specific activation process is as follows:

[0075] For the slurry bed reaction process: Load the finished powder catalyst prepared in step A7 above into a tubular furnace, and introduce hydrogen for programmed temperature and pressure reduction activation of the catalyst until no more water is generated; The reduction activation conditions are: temperature 420 °C, hydrogen volume space velocity 50 h -1 -1, hydrogen pressure 1.0 MPa. When in use, transfer the activated catalyst to a slurry bed reactor.

[0076] For the fixed-bed reaction process: The finished particulate catalyst prepared in the above step A7 is loaded into a fixed-bed reactor, and hydrogen is introduced for programmed temperature rise in-situ pressure reduction activation of the catalyst until no more water is generated; the reduction activation conditions are: temperature 350 °C, hydrogen volumetric space velocity 50 h -1 ⁻¹, hydrogen pressure 5.0 MPa. Subsequently, the temperature, hydrogen space velocity, and pressure of the fixed-bed reactor are adjusted to the set values for catalytic hydrogenation reaction.

[0077] Examples 11 - 16

[0078] C 4 Hydrogenation of a dicarboxylic acid or its substituted dicarboxylic acid to C 4 saturated polyol, and the specific process is as follows:

[0079] Mix hydrogen with an aqueous solution of C 4 dicarboxylic acid or its substituted dicarboxylic acid and preheat to 150 °C, then feed it into a slurry bed or fixed-bed reactor filled with pre-reduced and activated catalyst in series with one or two stages for hydrogenation reaction to prepare the corresponding C 4 polyol. Among them, when using a one-stage hydrogenation process, the raw material is fed into the hydrogenation reactor together with hydrogen and recycled material, and the recycle ratio is 1.0.

[0080] The hydrogenation reaction conditions are: raw material C 4 dicarboxylic acid and / or its substituted dicarboxylic acid solution concentration 10 - 60 wt%, total feed weight hourly space velocity 0.30 - 1.00 h -1 ⁻¹, reaction temperature 170 - 210 °C, system pressure 5.0 - 5.5 MPa, hydrogen / (ester group + carboxyl group + unsaturated bond) molar ratio 50 - 100. The C 4 polyols prepared by the hydrogenation reactions in Examples 11 - 16 are in turn: BDO, BDO, 1,2,4-butanetriol, 1,2,4-butanetriol, 1,2,3,4-butanetetraol, 2,2,3,3-tetrafluoro-1,4-butanediol.

[0081] The specific reaction process, reactor form, catalyst, reaction process conditions, and catalytic reaction results are listed in Table 2 respectively. Note: In Table 2, for example, in Example 11, a two-stage series hydrogenation reaction process is adopted. "P2-CSR-IFR" indicates the use of a two-stage series hydrogenation process, and the first and second hydrogenation reactors use CSR and IFR respectively. "Cat-4 / -9" indicates that the catalyst used in the first-stage hydrogenation reaction is the catalyst numbered Cat-4, and the catalyst used in the second-stage hydrogenation reaction is the catalyst numbered Cat-9. The reaction temperature of "160 / 220" °C means that the reaction temperatures of the first and second-stage hydrogenation reactions are 160 °C and 200 °C respectively. For other examples, it can be inferred by analogy.

[0082] Comparative Example 1

[0083] The preparation of 1,4 - butanediol by one - step hydrogenation of succinic acid in a kettle is as follows:

[0084] Referring to the method of Patent CN109453763A, hydrogenation of aqueous succinic acid solution was carried out to prepare BDO. The Ru / SiO 2 -TiO 2 catalyst (the mass contents of Ru, SiO 2 and TiO 2 are 15%, 55% and 30% respectively) was reduced and activated at 220 °C and 1.0 MPa, and then transferred to an autoclave. An aqueous succinic acid solution with a concentration of 20 wt% was added, and the hydrogenation reaction was carried out at a pressure of 5.5 MPa and a temperature of 210 °C for 4.0 h. The conversion rate of succinic acid was 99.3%, and the selectivity of BDO was 90.8%. The reaction results are listed in Table 2.

[0085] Table 2 Catalysts, process conditions and reaction results for hydrogenation of C4 dicarboxylic acids and their esters to C 4 Saturated polyhydric alcohols

[0086]

[0087] According to the results in Table 2, it can be seen that for the hydrogenation of C 4 dicarboxylic acids and their substituted dicarboxylic acids to prepare the corresponding C 4 saturated polyhydric alcohols, under the conditions of one - stage or two - stage hydrogenation reaction process and the corresponding reactors, catalysts and process conditions, the conversion rate is 95.6 - 100%, and the selectivity of the corresponding C 4 saturated polyhydric alcohol is 91.2 - 94.2%. Comparing Examples 13, 14 and Comparative Example 1, it can be seen that in this invention, the multi - component RuRe - CuZnZrCe / (SBA - 15) - Si catalyst and the one - stage isothermal fixed - bed material circulation (circulation ratio 1.0) process (Example 14) and the two - stage jacket heat - transfer slurry bed - inter - stage heat - exchange adiabatic fixed - bed reactor series process are adopted. The conversion rates of succinic acid are 98.2% and 98.8% respectively, and the selectivities of BDO are 93.7% and 94.2% respectively, which are significantly higher than the selectivity of 90.8% of the prior art (Comparative Example 1) using a single noble metal catalyst and a one - step process without material circulation. Obviously, adopting a multi - component catalyst and a one - stage material circulation process or a two - stage series reaction process can improve the selectivity of the target product. In particular, the multi - stage series reaction process can also adapt to higher - concentration raw materials and higher space velocities.

[0088] Examples 17 - 22

[0089] C 4 Hydrogenation of monohydric alcohol monoesters of straight - chain dicarboxylic acids to 1,4 - butanediol:

[0090] Mix the hydrogen gas with a solution of a monohydric alcohol monoester of a C4 linear dibasic acid and preheat it to 150 °C, then feed it into a slurry bed or fixed bed reactor filled with a pre-reduced and activated catalyst in series with one or two stages to carry out a hydrogenation reaction to prepare 1,4-butanediol. Among them, when adopting a one-stage hydrogenation process, the raw materials, hydrogen gas and recycled materials are fed into the hydrogenation reactor together, and the recycle ratio is 0.5.

[0091] The hydrogenation reaction conditions are as follows: the raw material C 4 The concentration of the solution of the linear dibasic acid monoester is 15-50 wt%, the total feed weight hourly space velocity is 0.40-0.75 h -1 , the reaction temperature is 180-210 °C, the system pressure is 5.0-6.0 MPa, and the molar ratio of hydrogen gas / (ester group + carboxyl group + unsaturated bond) is 75-100.

[0092] The specific reaction process, reactor form, catalyst, raw materials, reaction process conditions and catalytic reaction results are listed in Table 3 respectively.

[0093] Table 3 C 4 Catalyst, process conditions and reaction results for the hydrogenation of dibasic acids and their esters to saturated polyols 4

[0094]

[0095] According to Table 3, it can be seen that for the hydrogenation of the linear dibasic acid monoester to prepare BDO, under the conditions of adopting a one-stage or two-stage hydrogenation reaction process and the corresponding reactor, catalyst and process conditions, the conversion rate is 95.7-100%, and the selectivity of BDO is 92.5-95.2%. 4

[0096] Examples 23-36

[0097] C 4 Hydrogenation of the dihydric alcohol diester of dibasic acid to C 4 Saturated polyols:

[0098] Mix the solution of the linear dibasic acid diester or the solution of the branched dibasic acid diester or the solution of the substituted dibasic acid diester with hydrogen gas, preheat it to 150 °C, and feed it into a slurry bed or fixed bed series reactor filled with a pre-reduced and activated catalyst. Adopt a two-stage or three-stage hydrogenation process to carry out a hydrogenation reaction to prepare the corresponding C 4 4 4 4 Saturated polyols: 1,4-butanediol (BDO), 2-methyl-1,3-propanediol (MPO), and 1,2,4-butanetriol or 1,2,3,4-butanetetraol.

[0099] The hydrogenation reaction conditions are as follows: the raw material C 4The concentration of the diester solution of the dibasic acid is 40-100 wt%, the total feed weight hourly space velocity is 0.25-0.50 h -1 , the reaction temperature is 170-240 °C, the system pressure is 5.0-6.5 MPa, and the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 75-100.

[0100] The specific reaction process, reactor form, catalyst, reaction process conditions and catalytic reaction results are listed in Table 4 respectively.

[0101] Comparative Example 2

[0102] Preparation of 1,4-butanediol by two-step hydrogenation of dimethyl maleate:

[0103] Referring to the method provided in Patent CN103946201B, BDO was prepared by two-step hydrogenation of dimethyl maleate (DMM). The catalysts for the first-step reaction with a diameter of 2.2 mm and a length of 3-5 mm in the shape of a clover were prepared by the impregnation method and the co-precipitation method, respectively, with 0.5 wt% Pd / Al 2 O 3 and the catalyst for the second-step reaction was 62% CuO-30% ZnO-8% BaO (CuZnBa). The two catalysts were respectively loaded into two series-connected adiabatic fixed-bed reactors, and hydrogen was introduced to reduce and activate them at 250 °C, 5.0 MPa and 350 °C, 5.0 MPa, respectively. Then, at a concentration of 50 wt% of the THF solution of DMM, a feed liquid hourly space velocity of 0.4 h -1 , a hydrogen / ester molar ratio of 50 and a system pressure of 5.0 MPa, the first-step reaction of hydrogenating DMM to prepare DMS and the second-step reaction of hydrogenating DMS to prepare BDO were carried out at 90 °C and 190 °C, respectively.

[0104] In the first-step reaction, the conversion rate of DMM was 100%, and the selectivity of DMS was 98.0%; in the second-step reaction, the conversion rate of DMS was 98.2%, the selectivity of BDO was 76.8%, THF was 13.5% and GBL was 5.2%. The overall results of the two-step reaction: the conversion rate of DMM was 100%, the selectivity of BDO was 73.9%, THF was 13.0% and GBL was 5.0%.

[0105] Comparative Examples 3-5

[0106] Preparation of 1,4-butanediol by two-step hydrogenation of dimethyl maleate:

[0107] The reduction activation of the catalyst and the hydrogenation reaction process and operating conditions of DMM were the same as those in Example 23, except that: in Comparative Example 3, the catalysts for both steps of the reaction were loaded with the noble metal catalyst Pd / Al of Comparative Example 2 2 O 3, for Comparative Example 4, the catalysts for the two-step reaction were both loaded with the copper-based catalyst CuZnBa of Comparative Example 2. For the first step of Comparative Example 5, the noble metal catalyst Pd / Al of Comparative Example 2 was loaded. 2 O 3 For the second step, the copper-based catalyst CuZnBa of Comparative Example 2 was loaded. The results are shown in Table 4. The DMM conversion rates of Comparative Examples 3-5 were all 100%, and the BDO selectivities were 12.6%, 6.8% and 85.5% respectively. Obviously, when using a single noble metal catalyst or a single copper-based catalyst, the main product formed by the hydrogenation reaction is not BDO, and mainly the hydrogenation incomplete products are formed.

[0108] Table 4C 4 Catalyst, process conditions and reaction results for hydrogenating dibasic acids and their esters to C 4 saturated polyhydric alcohols

[0109]

[0110] From the results in Table 4, it can be seen that for C 4 hydrogenating dibasic acid diesters to prepare the corresponding C 4 saturated polyhydric alcohols, under the conditions of using a two-stage or three-stage hydrogenation reaction process and the corresponding reactor, catalyst and process conditions, the conversion rate is 96.3-100%, and the C 4 saturated polyhydric alcohol selectivity is 91.2-94.8%.

[0111] By comparing Example 23 with Comparative Example 2, it can be found that: the present invention uses two series-connected reactors of an external circulation heat exchange slurry bed - isothermal fixed bed, and the same multi-component multifunctional catalyst PtSn-CuZnAlBa / Al in the forms of powder and clover particles 2 O 3 -Si to prepare BDO by one-step hydrogenation of DMM, hydrogenating the C=C double bond and two ester groups in the DMM molecule simultaneously, and achieving good reaction results, with a DMM conversion rate of 100% and a BDO selectivity of 94.1%; while the prior art uses two catalysts for two-step reactions to hydrogenate the functional groups in the DMM molecule one by one, that is, using the noble metal catalyst Pd / Al 2 O 3 to first hydrogenate the double bond of DMM to prepare DMS, and then use the copper-based catalyst CuZnBa to hydrogenate the two ester groups of DMS to prepare BDO, with a large amount of BGL and THF by-produced at the same time, resulting in a BDO selectivity of only 73.9%.

[0112] Comparing Example 23 with Comparative Examples 3-5, it can be found that the multi-component multifunctional catalyst developed by the present invention, which consists of noble metal and non-noble metal active components, structural promoters and electronic promoters, high specific surface area pore materials and high thermal conductivity materials, and the two-stage series reaction process have high activity and selectivity for the one-step hydrogenation of DMM to prepare BDO; while using the prior art noble metal catalysts with extremely poor thermal conductivity prepared by impregnation method using traditional pore materials such as Al 2 O 3 etc. as carriers, or bulk copper-based catalysts with relatively small specific surface area prepared by co-precipitation method, and the combined catalysts using these two catalysts, the activity and selectivity of DMM hydrogenation to prepare BDO are both poor.

[0113] Examples 37-41

[0114] Hydrogenation of maleic acid or succinic acid diol mono / diester to 1,4-butanediol

[0115] Mix hydrogen with the BDO solution of maleic acid or succinic acid diol monoester or diester, preheat to 150 °C, and feed it into a slurry bed or fixed bed series reactor filled with a catalyst pre-reduced and activated in advance. Adopt a two-stage or three-stage hydrogenation process to carry out the hydrogenation reaction to prepare BDO.

[0116] The reaction conditions are as follows: the concentration of the raw material C 4 dicarboxylic acid diester solution is 40-60 wt%, the total feed weight hourly space velocity is 0.30-0.50 h -1 , the reaction temperature is 170-250 °C, the system pressure is 5.0-7.0 MPa, and the molar ratio of hydrogen / (ester group + carboxyl group + unsaturated bond) is 50-100. The specific reaction process, reactor form, catalyst, reaction process conditions and catalytic reaction results are listed in Table 5 respectively.

[0117] Table 5 C 4 Catalyst, process conditions and reaction results for hydrogenation of dicarboxylic acid and its ester to C 4 saturated polyhydric alcohol

[0118]

[0119] As can be seen from the results shown in Table 5, for the hydrogenation of maleic acid or succinic acid diol ester to prepare BDO, under the conditions of using a two-stage or three-stage hydrogenation reaction process and the corresponding reactor, catalyst and process conditions, the conversion rate is 98.5-100%, and the BDO selectivity is 90.5-95.3%.

[0120] In summary, the following conclusions can be drawn:

[0121] 1) The present invention provides C 4 direct hydrogenation of dicarboxylic acid and its ester to prepare C 4New method for saturated polyols, hydrogenating multiple functional groups (unsaturated bonds, carboxyl groups or / and ester groups) in dibasic acids and their esters simultaneously to generate corresponding C 4 saturated polyols in one step, with high activity and selectivity; existing technologies use multiple catalysts and multiple steps of reactions (catalysts and reactions for hydrogenating unsaturated bonds, carboxyl groups or ester groups in one or two steps), resulting in low selectivity of the target product. 4

[0122] 2) The present invention provides a C 4 high-efficiency catalyst for hydrogenating dibasic acids and their esters to prepare C 4 saturated polyols. By introducing a composite support of a pore material with a high specific surface area and a heat-conducting material with a high thermal conductivity, and using a method combining deposition precipitation and incipient wetness impregnation, a new multi-component and multi-functional catalyst containing both noble metal and non-noble metal active components, containing structural promoters and electronic promoters, and containing a dual support is prepared.

[0123] 3) The present invention provides a C 4 new process for hydrogenating dibasic acids and their esters to prepare C 4 saturated polyols, adopting a one-stage to three-stage series reaction process (one reactor with 1 - 3 beds or 2 - 3 series reactors), and an external circulation cooling or jacket heat removal slurry bed reactor or / and inter-stage quenching adiabatic fixed bed or shell-and-tube heat removal isothermal fixed bed reactor, and controlling the conversion rate and hydrogenation depth by controlling the reaction temperature, so that C 4 dibasic acids and their esters are converted into C 4 saturated polyols with high activity and high selectivity.

[0124] 4) By adopting the above new method, new catalyst and new process, the present invention realizes the efficient hydrogenation of C 4 dibasic acids and their esters in one step to generate C 4 saturated polyols, simplifies the process flow, saves equipment investment, reduces material and energy consumption, and thus can significantly reduce production costs. The technology provided by the present invention has generality and universality, and a series of C 4 saturated polyols, such as BDO, MPO, 1,2,4 - butanetriol, etc., can be produced using this technology.

[0125] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.​

Claims

1. A production process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or their esters, characterized in that: The raw material C4 dibasic acid and / or its ester is subjected to catalytic hydrogenation reaction in the presence of a multifunctional hydrogenation catalyst to prepare C4 saturated polyol, wherein the hydrogenation reaction adopts a one-stage, two-stage or three-stage series hydrogenation reaction process, and the hydrogenation reactor used for the hydrogenation reaction is a slurry bed reactor or / and a fixed bed reactor; wherein, When the hydrogenation reaction adopts a one-stage hydrogenation reaction material external circulation process, the process includes the following operation flow: hydrogen and C4 dibasic acid and / or its ester solution are mixed and preheated to 120-180° C., and sent together with the circulating material into a slurry bed or fixed bed reactor filled with a pre-reduced activated catalyst to carry out a catalytic hydrogenation reaction; the hydrogenation reaction process conditions are: the concentration of the raw material C4 dibasic acid and / or its ester solution is 10-100wt%, the total feed weight hourly space velocity (new material + circulating material) is 0.10-1.50h -1 , liquid phase hydrogenation material circulation ratio 0-5.0, reaction temperature 150-250°C, system pressure 3.0-8.0MPa, hydrogen / (ester group+carboxyl group+unsaturated bond) molar ratio 20-200; or, When the hydrogenation reaction adopts a two-stage series hydrogenation reaction process, the process includes the following operation flow: hydrogen and C4 dibasic acid and / or its ester solution are mixed and preheated to 120-180°C, first sent to a first-stage slurry bed or fixed bed filled with a pre-reduced activated catalyst for hydrogenation reaction, and the first-stage hydrogenation material is then sent to a second-stage slurry bed or fixed bed filled with a pre-reduced activated catalyst in series to continue hydrogenation reaction, the first-stage and second-stage hydrogenation catalysts are the same or different, and the two-stage series reactor is a reactor containing two beds of the first and second stages or two reactors in series; the hydrogenation reaction process conditions are: the two-stage hydrogenation reactions adopt the same feed space velocity and system pressure, the feed C4 dibasic acid and / or its ester solution concentration is 10-100wt%, the feed weight hourly space velocity is 0.10-1.00h -1 , system pressure 3.0-8.0 MPa, hydrogen / (ester group+carboxyl group+unsaturated bond) molar ratio 20-200, first stage reaction temperature 150-230°C, second stage reaction temperature 170-260°C; or, When the hydrogenation reaction adopts a three-stage series hydrogenation reaction process, the process includes the following operation flow: the three-stage series hydrogenation reaction process includes the following operation flow: hydrogen and C4 dibasic acid and / or its ester solution are mixed and preheated to 120-180°C, and then sequentially fed into a series of slurry beds or fixed beds filled with pre-reduced activated catalysts for three-stage hydrogenation reactions, the catalysts of the three-stage reactions are the same or different, and the three-stage series reactor is a reactor containing three beds of the first stage, the second stage and the third stage or three reactors in series; the hydrogenation reaction process conditions are: the three-stage hydrogenation reactions all adopt the same feed space velocity and system pressure, the feed C4 dibasic acid and / or its ester solution concentration is 10-100wt%, the feed weight hourly space velocity is 0.15-1.50h -1 , system pressure 3.0~8.0MPa, hydrogen / (ester group+carboxyl group+unsaturated bond) molar ratio 20~200, first stage reaction temperature 150~220℃, second stage reaction temperature 170~240℃, third stage reaction temperature 190~260℃.

2. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or their esters according to claim 1, characterized in that: When the hydrogenation reaction adopts a one-stage hydrogenation reaction material external circulation process, the hydrogenation reaction process conditions are: the concentration of the raw material C4 dibasic acid and / or its ester solution is 15-75wt%, the total feed weight hourly space velocity (new material + circulating material) is 0.20-1.00h -1 , liquid phase hydrogenation material circulation ratio 0-2.5, reaction temperature 160-230°C, system pressure 4.0-7.0MPa, hydrogen / (ester group+carboxyl group+unsaturated bond) molar ratio 35-150; Preferably, the hydrogenation reaction process conditions are: the concentration of the raw material C4 dibasic acid and / or its ester solution is 20-50wt%, the total feed weight hourly space velocity is 0.40-0.75h -1 , liquid phase hydrogenation material circulation ratio 0.5-2.0, reaction temperature 170-210°C, system pressure 4.5-6.5MPa, hydrogen / (ester group+carboxyl group+unsaturated bond) molar ratio 50-100.

3. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or esters thereof according to claim 1, characterized in that: When the hydrogenation reaction adopts a two-stage series hydrogenation reaction process, the hydrogenation reaction process conditions are: the feed C4 dibasic acid and / or its ester solution concentration is 25-80wt%, the feed weight hourly space velocity is 0.20-0.75h -1 , system pressure 4.0-7.0 MPa, hydrogen / (ester group+carboxyl group+unsaturated bond) molar ratio 35-150, first stage reaction temperature 160-210°C, second stage reaction temperature 180-240°C; Preferably, the hydrogenation reaction process conditions are: the feed C4 dibasic acid and / or its ester solution concentration is 40-60wt%, the feed weight hourly space velocity is 0.30-0.60h -1 , system pressure 4.5-6.5 MPa, hydrogen / (ester group + carboxyl group + unsaturated bond) molar ratio 50-100, first stage reaction temperature 170-190°C, second stage reaction temperature 190-220°C.

4. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or their esters according to claim 1, characterized in that: When the hydrogenation reaction adopts a three-stage series hydrogenation reaction process, the hydrogenation reaction process conditions are: the feed C4 dibasic acid and / or its ester solution concentration is 25-90wt%, the feed weight hourly space velocity is 0.20-1.00h -1 , system pressure 4.0-7.0 MPa, hydrogen / (ester group+carboxyl group+unsaturated bond) molar ratio 35-150, first stage reaction temperature 160-210°C, second stage reaction temperature 180-230°C, third stage reaction temperature 200-250°C; Preferably, the hydrogenation reaction process conditions are: the feed C4 dibasic acid and / or its ester solution concentration is 40-80wt%, the feed weight hourly space velocity is 0.30-0.75h -1 , system pressure 4.5-6.5 MPa, hydrogen / (ester group + carboxyl group + unsaturated bond) molar ratio 50-100, first stage reaction temperature 170-200°C, second stage reaction temperature 190-220°C, third stage reaction temperature 210-240°C.

5. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or esters thereof according to claim 1, characterized in that: The slurry bed reactor is selected from a fully mixed flow external circulation cooling and heat exchange slurry bed reactor or a fully mixed flow jacket medium heat transfer slurry bed reactor; the fixed bed reactor is selected from a plug flow inter-stage rapid cooling heat exchange adiabatic fixed bed reactor or a plug flow shell and tube medium heat transfer isothermal fixed bed reactor.

6. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or their esters according to claim 1, characterized in that: The multifunctional hydrogenation catalyst comprises: a dual active component consisting of a noble metal and a non-noble metal, a dual carrier consisting of a high specific surface porous material and a high thermal conductivity material, and a metal oxide structural additive and an electronic additive; wherein the noble metal is selected from at least one of Ru, Os, Rh, Ir, Pd or Pt, and the non-noble metal is selected from at least one of Cr, Mn, Fe, Co, Ni or Cu; the metal oxide structural additive is at least one of Ga, In, Sn, Nb, Mo, W, Re, Al, Ti, Zr or Zn oxides, the electronic additive is selected from at least one of alkaline earth or rare earth metal oxides, the high specific surface porous material is selected from at least one of aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, zeolite molecular sieve or clay, and the high thermal conductivity material is selected from at least one of α-Al2O3, Si, α-SiO2, SiC, Mo2C or BN.

7. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or their esters according to claim 6, characterized in that: In the composition of the multifunctional hydrogenation catalyst, the precious metal is selected from one or two of Ru, Pd or Pt, the non-precious metal is selected from one or two of Mn, Ni or Cu, the metal oxide structural additive includes a first structural additive and a second structural additive, and the first structural additive is selected from at least one of Al, Ti, Zr or Zn, and the second structural additive is selected from at least one of Ga, In, Sn, Re; the electronic additive is selected from one or two of Sc, Y, Mg, Ba, La or Ce oxides, the high specific surface area pore material is selected from one or two of γ-Al2O3, mesoporous alumina, SiO2, mesoporous silica, TiO2, ZrO2, MCM-41, MCM-48, SBA-15, hydroxyapatite or diatomaceous earth, and the high thermal conductivity material is selected from α-Al2O3, Si, α-SiO2 or SiC.

8. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or their esters according to claim 6 or 7, characterized in that: In the multifunctional hydrogenation catalyst, the non-precious metal component accounts for 35-60wt%, the precious metal component accounts for 0.1-7.5wt%, the structural additive accounts for 5.0-35.0wt%, the electronic additive accounts for 1.0-7.5wt%, the high specific surface area carrier accounts for 10-30wt%, and the high thermal conductivity carrier accounts for 2.0-15.0wt%; Preferably, non-precious metal components account for 40-55wt%, precious metal components account for 0.5-5.5wt%, structural additives account for 10-30wt%, electronic additives account for 2.0-5.0wt%, high specific surface area carriers account for 15-25wt%, and high thermal conductivity carriers account for 5.0-10.0wt%.

9. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or esters thereof according to claim 1, characterized in that: C4 dibasic acids and esters thereof include maleic acid, fumaric acid, succinic acid, butynedioic acid, methylmalonic acid, methylenemalonic acid or / and substituted dibasic acids thereof, and esters of these dibasic acids with aliphatic alcohols, alicyclic alcohols, aromatic alcohols or heterocyclic alcohols; Preferably, the C4 dibasic acid and its ester include maleic acid, fumaric acid, succinic acid, acetylenedioic acid, methylmalonic acid, methylenemalonic acid, 2-hydroxymethylmalonic acid, malic acid, tartaric acid, 2-mercaptosuccinic acid, 2,3-dimercaptosuccinic acid, 2-chlorosuccinic acid, 2,3-dichlorosuccinic acid, 2-fluorosuccinic acid, 2,2-difluorosuccinic acid or tetrafluorosuccinic acid, and monoesters, diesters or / and polyesters of these dibasic acids with mono- or di-basic C1-C8 fatty alcohols, C5-C9 alicyclic alcohols, C7-C9 aromatic alcohols or C3-C7 heterocyclic alcohols; More preferably, the C4 dibasic acid and its esters include maleic acid, fumaric acid, succinic acid, acetylenedioic acid, methylmalonic acid, methylenemalonic acid, 2-hydroxymethylmalonic acid, malic acid, tartaric acid, 2-chlorosuccinic acid or tetrafluorosuccinic acid, and the esters of these dibasic acids and methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, amyl alcohol, isopentanol, neopentyl alcohol, hexanol, heptanol, octanol, isobutyl alcohol, tert-butyl alcohol, pentyl alcohol, isopentanol, neopentyl alcohol, hexanol, heptanol, octanol, isobutyl alcohol, tert- ... Octanol, or allyl alcohol, methylallyl alcohol, crotyl alcohol, isopentenol, propargyl alcohol, butynol, or cyclopentanol, cyclohexanol, 4-methylcyclohexanol, cyclohexylmethanol, cyclohexylpropanol, or 2-chloroethanol, 3-chloropropanol, 4-chlorobutanol, 2,2,2-trifluoroethanol, or benzyl alcohol, α-phenylethanol, β-phenylethanol, α-methylphenylethanol, hydrocinnamic alcohol, cinnamic alcohol, or glycidol, tetrahydrofurfuryl alcohol, Mono- or / and diesters of furfuryl alcohol, nicotinic alcohol, 2-pyridinemethanol, 4-piperidinylmethanol or 2-thiophenemethanol, and mono- or / and diesters thereof with ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, 1,2-propylene glycol, dipropylene glycol, polypropylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 2,3-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-1, Monoesters, diesters or / and polyesters of 3-propylene glycol, neopentyl glycol, 1,4-butenediol, 1,4-butynediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, o-phthalic alcohol, m-phthalic alcohol, p-phthalic alcohol, 2,5-furan dimethanol or 2,6-pyridine dimethanol.

10. The process for preparing C4 saturated polyols by hydrogenating C4 dibasic acids and / or their esters according to claim 1, characterized in that: The C4 saturated polyol includes 1,4-butanediol or 2-methyl-1,3-propanediol or a substituted polyol thereof; Preferably, the C4 saturated polyol includes 1,4-butanediol, 2-methyl-1,3-propanediol, trimethylolmethane, 1,2,4-butanetriol, 1,2,3,4-butanetetrol, 2-mercapto-1,4-butanediol, 2,3-dimercapto-1,4-butanediol, 2-chloro-1,4-butanediol, 2,3-dichloro-1,4-butanediol, 2-fluoro-1,4-butanediol, 2,2-difluoro-1,4-butanediol or 2,2,3,3-tetrafluoro-1,4-butanediol; More preferably, the C4 saturated polyol is 1,4-butanediol, 2-methyl-1,3-propanediol, trimethylolmethane, 1,2,4-butanetriol, 1,2,3,4-butanetetrol, 2-chloro-1,4-butanediol or 2,2,3,3-tetrafluoro-1,4-butanediol.

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