Method for preparing succinate from maleic anhydride

Abstract

The invention provides a method for preparing succinate from maleic anhydride, which comprises the following steps of: performing esterification reaction on maleic anhydride and alcohol serving as raw materials in the presence of an esterification catalyst to prepare maleic acid monoester or / and diester; under the action of a hydrogenation catalyst, maleic acid monoester or / and diester is subjected to double-bond selective hydrogenation to prepare succinic acid monoester or / and diester, and the esterification reaction and the hydrogenation reaction are subjected to two-step series connection or one-step coupling to prepare succinic acid ester; the esterification catalyst is selected from halogenated carboxylic acid or anhydride with a structural formula of RCOOH or (RCOO) 2O, or halogenated sulfonic acid, alkyl sulfonic acid or halogenated alkyl sulfonic acid or ester, salt or anhydride thereof with a structural formula of R 'SO3M or (R' SO2) 2O, or dihalogenated sulfimide or dihalogenated alkyl sulfimide or salt thereof with a structural formula of [(R 'SO2) 2N] mM, the hydrogenation catalyst is selected from a supported monometal or bimetallic catalyst with a structural formula of aA1-bA2 / (cZ1 + dZ2). The esterification catalyst is high in reaction efficiency, small in usage amount and easy to recycle; the hydrogenation catalyst is mild in reaction condition and high in activity and selectivity.

Description

Technical Field

[0001] The invention belongs to the field of chemical intermediates, and in particular relates to a method for preparing succinate esters by using maleic anhydride. Background Art

[0002] Succinates are important organic synthesis intermediates and material monomers, and are mainly used in the fields of drug synthesis, organic pigments, functional materials, etc. Among them, succinic acid monoesters include C1-C4 low-carbon monohydric alcohol esters, C8 and above high-carbon monohydric alcohol esters and C2-C4 polyhydric alcohol esters, as well as special esters such as L-menthyl ester, florfenicol ester, probucol ester, oleanolic acid ester and diosgenin ester, which are mainly used as fine chemical raw materials or directly as drugs, surfactants, etc.; succinic acid diesters mainly include C1-C8 monohydric fatty alcohol and aromatic alcohol esters, C2-C4 dihydric fatty alcohol esters, etc., which are widely used in flavors, coatings, food, medicine, plastics, rubber and other industries.

[0003] There are many methods for synthesizing succinic esters, such as direct esterification of succinic acid and alcohol, ring-opening esterification of succinic anhydride and alcohol, maleic ester hydrogenation, maleic anhydride hydrogenation esterification, maleic anhydride esterification reduction, etc.

[0004] Succinic anhydride obtained by hydrogenation of maleic anhydride and alcohol ring-opening esterification are used to prepare succinic acid monoesters and diesters. For example, CN104557536B discloses a method for preparing monomethyl succinate, wherein succinic anhydride and methanol are passed into a static mixer for monoesterification reaction, and the reaction effluent is then passed into an ultra-gravity reactor for reaction, and water vapor is passed into the ultra-gravity reactor at the same time. After the reaction, the liquid phase material is cooled and separated to obtain monomethyl succinate, and the optimized process conditions are succinic anhydride and methanol molar ratio 1:1.5-2.5, reaction temperature 90-120°C, reaction pressure 0.2-2.0MPa (ensuring that the reaction material is liquid phase), residence time 1-2h and material cooling temperature 10-15°C. CN110256244B discloses a method for synthesizing diisopropyl succinate, wherein succinic anhydride and isopropanol are used as raw materials, and acidic resin and solid superacid are used as catalysts for segmented catalytic continuous production of diisopropyl succinate.

[0005] Succinate is prepared by hydrogenating maleic acid ester obtained by esterification of maleic anhydride. For example, CN102001939B discloses a method for preparing succinic acid dicarboxylate, wherein hydrogen and maleic acid dicarboxylate are mixed and passed through a fixed bed reactor equipped with a hydrogenation catalyst, and the generated succinic acid dicarboxylate is partially used as a circulating dilution heat transfer material, the hydrogenated material is separated by gas and liquid, and the hydrogen is recycled, and the purity of the product succinic acid dicarboxylate exceeds 99.6%. CN101979139B provides a catalyst for preparing succinic acid dicarboxylate by hydrogenating maleic acid dicarboxylate and a preparation method thereof. The catalyst is prepared by an impregnation method, wherein the content of nickel in the active component is 5 to 25 wt%, the content of Na, K, Ca, Mg, Mn, Ba or Cu in the auxiliary agent is 0.5 to 8 wt%, and the rest is a carrier of alumina, silicon oxide, silicon-alumina composite oxide or activated carbon. The maleic acid dicarboxylate suitable for hydrogenation by the catalyst is a C1 to C5 carboxylate, and a fixed bed reaction process is adopted, the conversion rate of maleic acid dicarboxylate is 100%, and the selectivity of succinic acid dicarboxylate is above 99.6%. CN101745396B discloses a catalyst for hydrogenating dialkyl maleate to prepare dialkyl succinate, which is prepared by a coprecipitation method, wherein the main active component copper oxide accounts for 40-60%, the auxiliary agent zinc oxide accounts for 20-50% and aluminum oxide accounts for 10-20%; the catalyst is reduced in a hydrogen flow at 300°C for 4 hours before use, and then heated to room temperature at a reaction temperature of 100°C, a hydrogen pressure of 5MPa, a hydrogen-ester molar ratio of 100 and a liquid hourly space velocity of 0.2h -1 CN101747189B provides a method for preparing dialkyl succinate by hydrogenating dialkyl maleate (C1-C5 alkyl ester), wherein a CuZnAl catalyst is loaded into a fixed bed reactor, hydrogen is introduced at 230°C, normal pressure, and a flow rate of 500ml / min for 12 hours for reduction, and then a raw material containing dialkyl maleate is introduced for hydrogenation reaction, and the liquid product is cooled and separated to obtain the target product; the hydrogenation reaction temperature is 80-120°C, the pressure is 0.1-7MPa, and the dialkyl maleate space velocity is 0.1-10h -1 , hydrogen ester molar ratio 5 to 250:1.

[0006] Maleic anhydride esterification hydrogenation or esterification electrolytic reduction is used to prepare succinate. For example, CN102070448B discloses a method for preparing dimethyl succinate, using maleic anhydride and methanol as raw materials, using acidic cation exchange resin catalyst and fixed bed catalytic distillation process to synthesize dimethyl maleate, and then using Al2O3, SiO2, TiO2, ZrO2 or activated carbon as carriers to load Pd catalyst and fixed bed reaction process to hydrogenate dimethyl maleate to prepare dimethyl succinate, maleic anhydride esterification conversion rate 100% and dimethyl maleate selectivity greater than 99%, dimethyl maleate hydrogenation conversion rate and dimethyl succinate selectivity are both greater than 99.8%. CN115745772A synthesizes succinate diester by two-step reaction of maleic anhydride esterification and maleic diester hydrogenation, maleic anhydride esterification conversion rate greater than 99.5%, maleic diester hydrogenation conversion rate greater than 99.5%, and succinate diester selectivity exceeds 99.7%. CN102863335B provides a method for preparing succinic acid diester, which uses maleic anhydride, alcohol and hydrogen as raw materials, carbon dioxide as solvent and acid catalyst, and one-step esterification and hydrogenation under the action of hydrogenation catalyst to prepare succinic acid diester, and the yield is greater than 99%. CN101824627B synthesizes dimethyl maleate through three steps of monoesterification, diesterification and re-esterification of maleic anhydride and anhydrous methanol, and then prepares dimethyl succinate through electrochemical reduction, and then cools and crystallizes in water and recrystallizes in methanol or ethanol solvent to obtain dimethyl succinate product, wherein monoesterification does not require catalyst, and diesterification and re-esterification both use sulfuric acid or hydrochloric acid catalyst.

[0007] Obviously, the current mainstream production route of succinate esters is to use maleic anhydride as the starting material, and then obtain purified product succinic anhydride or succinic acid by hydrogenation esterification of maleic anhydride, that is, first obtain purified product succinic anhydride or succinic acid, and then synthesize by esterification reaction with alcohol, or by esterification hydrogenation of maleic anhydride, that is, first obtain purified maleic ester by esterification with alcohol, and then synthesize by double bond catalytic hydrogenation. Starting from the product maleic anhydride, succinate esters are prepared by a multi-step refining process with at least two steps of reaction and intermediates that need to be separated and purified. There are few processes that use a one-step coupling reaction of esterification-hydrogenation or a two-step direct series reaction process of esterification and hydrogenation without separation and purification of intermediate products. There is even less attention paid to the overall integrated process starting from gaseous crude maleic anhydride and reducing the manufacturing cost of starting raw material maleic anhydride, resulting in limited reduction in the production cost of succinate esters. At present, the investment and production cost of maleic anhydride industrial equipment are mainly consumed in the solvent absorption and analysis of the gas phase maleic anhydride logistics of the oxidation reaction product, the separation and refining of crude maleic anhydride, and the purification and recovery of solvents. In addition, in the existing synthesis technology of succinate esters, the esterification catalyst mainly uses liquid acids such as sulfuric acid and hydrochloric acid, which are highly corrosive, polluting, and in large quantities, or solid acids such as acidic ion exchange resins and solid superacids, which are inefficient; the hydrogenation catalyst basically uses supported copper-based and nickel-based catalysts with low reaction activity and harsh use conditions, or precious metal catalysts with high loading and high price. Therefore, it is of great significance to design a new method for producing succinate esters from maleic anhydride via esterification-hydrogenation. Summary of the invention

[0008] In view of this, the present invention provides a method for producing succinate esters by using maleic anhydride including product maleic anhydride or gaseous crude maleic anhydride as raw materials through an esterification-hydrogenation one-step coupling reaction or an esterification and hydrogenation two-step series reaction.

[0009] To achieve the above purpose, the technical solution of the present invention is specifically as follows:

[0010] A method for preparing succinate esters from maleic anhydride comprises the following steps: using maleic anhydride and alcohol as raw materials, carrying out an esterification reaction in the presence of an esterification catalyst to prepare maleic acid monoesters or / and diesters; then, in the presence of a hydrogenation catalyst, selectively hydrogenating double bonds to prepare succinate esters or / and diesters, and the esterification reaction and the hydrogenation reaction are carried out in two steps in series or in one step in coupling to prepare succinate esters;

[0011] The esterification catalyst is selected from a halogenated carboxylic acid or anhydride of the structural formula RCOOH or (RCOO)2O, or a halogenated sulfonic acid, alkyl sulfonic acid or halogenated alkyl sulfonic acid or its ester, salt or anhydride of the structural formula R′SO3M or (R′SO2)2O, or a halogenated sulfonic acid of the structural formula [(R″SO2)2N] m M is a dihalogenated sulfonyl imide or a dihalogenated hydrocarbon sulfonyl imide or a salt thereof; R is a halogenated hydrocarbon group, R′ is a halogen, a hydrocarbon group or a halogenated hydrocarbon group, M is hydrogen, a hydrocarbon group or an ammonium, metal, pyridine, piperidine, guanidine, or imidazolium ion, R″ is a halogen or a halogenated hydrocarbon group, and m is an integer from 1 to 4;

[0012] The hydrogenation catalyst is selected from a supported monometallic or bimetallic catalyst with a structural formula of aA1-bA2 / (cZ1+dZ2), wherein A1 is a first active component noble metal, A2 is a second active component noble metal or transition metal, Z1 is a first carrier porous material, Z2 is a second carrier thermal conductive material, a, b, c and d are respectively the mass fractions of A1, A2, Z1 and Z2 in the catalyst, a=0.01-5.00%, b=0-10.00%, c=50.00-99.99%, d=0-49.99%.

[0013] The present invention is further configured that the esterification catalyst is selected from a halogenated carboxylic acid or anhydride with a structural formula of RCOOH or (RCOO)2O, an alkyl sulfonic acid, aryl sulfonic acid or anhydride with a structural formula of R′SO3H or (R′SO2)2O, or a n F 2n+ 1SO2)2O perfluorosulfonic anhydride, or a perfluorosulfonic anhydride having a structural formula of C n F 2n+1 SO3M perfluorosulfonic acid or its ester or salt, or the structural formula [(C n F 2n+ 1SO2)2N] m At least one of the bisperfluorosulfonyl imide or salt thereof of M; wherein R is a chlorinated or fluorinated C1-C3 alkyl group, and R′ is a C1-C3 alkyl group or a C6-C 10 Aryl, M is hydrogen, C1-C4 alkyl or ammonium, metal, pyridine, piperidine, guanidine or imidazole ion, n is an integer of 0-4, and m is an integer of 1-4.

[0014] The present invention is further configured that the esterification catalyst is selected from at least one of trichloroacetic acid, trifluoroacetic acid, perfluoropropionic acid, methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid or β-naphthalenesulfonic acid or their anhydrides, or fluorosulfonic acid or trifluoromethanesulfonic acid or their anhydrides or methyl esters or ethyl esters, or bis(trifluoromethanesulfonyl)imide or bis(trifluoromethanesulfonyl)imide, or salts of fluorosulfonic acid, trifluoromethanesulfonic acid, bis(trifluoromethanesulfonyl)imide of Li, Na, K, Ag, Mg, Ca, Sr, Ba, Ni, Cu, Zn, Al, In, Fe, Bi, Zr, Sn or rare earth or pyridine, piperidine, guanidine, imidazolium ions;

[0015] Preferably, the esterification catalyst is selected from at least one of trifluoroacetic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, fluorosulfonic acid, trifluoromethanesulfonic acid, trifluoromethanesulfonic anhydride, methyl fluorosulfonate, methyl trifluoromethanesulfonate, bis(trifluoromethanesulfonyl)imide, or a salt of Li, Mg, Cu, Zn, Al, In, Fe, Bi, Zr, Sn, Sc, La, Ce, Pr, Nd, Sm, Yb, or pyridine, N-butylpyridine sulfonate, N-alkylpyridine, piperidine, 1-ethyl-2-methylpiperidine, guanidine, imidazole, 1-alkylimidazole, 1-alkyl-3-methylimidazole with fluorosulfonic acid, trifluoromethanesulfonic acid, bis(trifluoromethanesulfonyl)imide or bis(trifluoromethanesulfonyl)imide.

[0016] The present invention is further configured that, in the hydrogenation catalyst, A1 is selected from Ru, Os, Rh, Pd or Pt, A2 is selected from Re, Ru, Ir, Cr, Mn, Fe, Co, Ni or Cu; Z1 has a specific surface area greater than 50m 2 / g porous material, selected from at least one of activated carbon, mesoporous carbon, carbon nanotubes, graphene, SiO2, γ-Al2O3, θ-Al2O3, mesoporous Al2O3, SiO2-Al2O3, TiO2, ZrO2, HM, HHEU, Hβ, HZSM-5, HZSM-22, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-56, SBA-15, ZEO-1, ZEO-3 or KIT-6; Z2 is a thermal conductivity greater than 5W / cm 2 The thermally conductive material is selected from graphite, Si, BeO, MgO, α-Al2O3, α-SiO2, ZrO2, BN, AlN, SiC, ZrC, Mo2C, W2C or WC; a=0.05-3.00%, b=0-7.50%, c=55.00-99.95%, d=0-44.95%;

[0017] Preferably, A1 is Ru, Pd or Pt, A2 is Ru, Co, Ni or Cu, and Z1 is a metal with a specific surface area greater than 100 m 2 / g activated carbon, SiO2, γ-Al2O3, SiO2-Al2O3, TiO2, ZrO2, HM, Hβ, HZSM-5, HMCM-22, HMCM-41 or SBA-15, Z2 is a thermal conductivity greater than 10W / cm 2 Graphite, Si, α-Al2O3, α-SiO2 or SiC, a = 0.10 ~ 2.00%, b = 0 ~ 5.00%, c = 60.00 ~ 99.90%, d = 0 ~ 39.90%;

[0018] More preferably, A1 is Ru, Pd or Pt, A2 is Ru or Ni, and Z1 is a metal with a specific surface area greater than 200 m 2 / g activated carbon, SiO2, γ-Al2O3, HM, HZSM-5 or SBA-15, Z2 is thermal conductivity greater than 20W / cm 2 Graphite, Si or SiC, a=0.20~1.00%, b=0~5.00%, c=65.00~99.80%, d=0~34.80%.

[0019] The present invention is further configured that the preparation method of the hydrogenation catalyst comprises the following steps: 1) preparing an aqueous solution or a dilute acid aqueous solution of a metal element Ru, Os, Rh, Pd or Pt compound corresponding to component A1; 2) preparing an aqueous solution or a dilute acid aqueous solution of a metal element Re, Ru, Ir, Cr, Mn, Fe, Co, Ni or Cu compound corresponding to component A2; 3) placing the porous material Z1 or the powder of Z1 and the thermal conductive material Z2 in a synthesis reactor according to a stoichiometric ratio, and using the prepared solution of the metal element compound corresponding to component A1 or the prepared solution of components A1 and A2 corresponding to the metal element compound; The metal element compound solution is immersed in equal volume at 30-50°C for 15-45 minutes, evaporated to dryness, and the cake is crushed, then calcined at 300-350°C for 1-3 hours and 500-600°C for 3-5 hours to obtain a powder catalyst; 4) 3-10wt% of methyl cellulose, 1-3wt% of graphite and an appropriate amount of water are added to the powder catalyst, mixed evenly and extruded into a shape, and then calcined at 300-350°C for 1-3 hours and 500-600°C for 3-5 hours to obtain a granular catalyst with a particle size of 1.6-3.0 mm and a length of 2.5-5.0 mm.

[0020] The present invention is further configured to use hydrogen to reduce the powder catalyst offline before use, and to reduce the particle catalyst online in situ, and the reduction conditions are: hydrogen space velocity 10 to 100 h -1 , temperature 120~350℃, reduction time 2~6h, preferably hydrogen space velocity 20~50h -1 , temperature 150 ~ 300 ℃, reduction 3 ~ 5h.

[0021] The present invention is further configured that the esterification reaction uses liquid maleic anhydride or solid maleic anhydride and alcohol for esterification, or uses alcohol to absorb gaseous maleic anhydride for absorption esterification;

[0022] When liquid maleic anhydride or solid maleic anhydride is used to carry out esterification reaction with alcohol, the esterification reaction includes the following process: firstly, the product maleic anhydride is mixed with alcohol and esterification catalyst according to the stoichiometric ratio and heated to dissolve, and then sent to a batch or continuous kettle reactor with or without an internal reflux condensing device, or sent to a tubular reactor, to carry out esterification reaction, and obtain an esterification reaction liquid containing maleic acid ester;

[0023] The process conditions are: raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (1.00-10.00): (0-0.001), reaction temperature 50-120° C., reaction pressure 0.10-2.00 MPa, intermittent reaction time or continuous reaction residence time 0.20-5.00 h; preferably, raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (1.02-5.00): (0-0.0005), reaction The temperature is 55-105°C, the reaction pressure is 0.10-1.50 MPa, and the intermittent reaction time or the continuous reaction residence time is 0.50-2.50 h; more preferably, the raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (1.05-2.00): (0-0.0001), the reaction temperature is 60-90°C, the reaction pressure is 0.10-1.00 MPa, and the intermittent reaction time or the continuous reaction residence time is 0.75-1.50 h;

[0024] Alternatively, alcohol is used to absorb gaseous maleic anhydride for absorption esterification, and the absorption esterification reaction includes the following process: a maleic anhydride gas stream generated by oxidation of benzene or butane which has been quenched is sent from the bottom to an absorption tower, and an alcohol absorbent containing an esterification catalyst is sprayed from the top of the tower, and the maleic anhydride gas stream and the absorbent are operated in countercurrent, and an absorption esterification liquid containing maleic ester is obtained by spraying absorption or bubbling absorption;

[0025] The process conditions are as follows: the absorption tower adopts a spray absorption tower or a bubbling absorption tower, the temperature of the maleic anhydride gas flow is 55-120°C and the pressure is 0.11-1.00 MPa, the temperature of the alcohol absorbent is 25-85°C, the concentration of the esterification catalyst in the absorbent is 0-0.0005wt%, the residence time of the absorbent is 0.20-2.00h, and the temperature of the absorption liquid is 50-90°C; preferably, the temperature of the maleic anhydride gas flow is 60-105°C and the pressure is 0.13-0.75MP ... and the temperature of the alcohol absorbent is 35-75°C, esterification catalyst concentration in the absorbent is 0-0.0002wt%, absorbent residence time is 0.30-1.50h, and absorption liquid temperature is 55-85°C; more preferably, maleic anhydride gas flow temperature is 65-90°C and pressure is 0.15-0.50MPa, alcohol absorbent temperature is 45-65°C, esterification catalyst concentration in the absorbent is 0-0.0001wt%, absorbent residence time is 0.50-1.00h, and absorption liquid temperature is 60-80°C. The present invention is further configured to prepare maleic acid diester by ring-opening esterification of liquid maleic anhydride or solid maleic anhydride and alcohol, and the esterification reaction includes the following process: first, maleic anhydride product is mixed with alcohol and esterification catalyst according to the stoichiometric ratio and heated to dissolve, and then sent to an intermittent or continuous autoclave reactor with an internal reflux condensing device to carry out esterification reaction to obtain an esterification reaction liquid containing maleic acid ester;

[0026] The process conditions are: raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (2.00-10.00): (0.0005-0.10), reaction temperature 70-150° C., reaction pressure 0.1-2.0 MPa, intermittent reaction time or continuous reaction residence time 0.50-10.00 h; preferably, raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (2.10-5.00): (0.001-0.05) , reaction temperature 75 ~ 135 ℃, reaction pressure 0.1 ~ 1.0 MPa, intermittent reaction time or continuous reaction residence time 0.75 ~ 5.00h; More preferably, the raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (2.25 ~ 3.00): (0.002 ~ 0.02), reaction temperature 80 ~ 120 ℃, reaction pressure 0.1 ~ 0.5 MPa, intermittent reaction time or continuous reaction residence time 1.00 ~ 2.50h;

[0027] Alternatively, maleic acid diester is prepared by alcohol absorption and ring-opening esterification of maleic anhydride gas stream, wherein the esterification reaction comprises the following steps: a maleic anhydride gas stream generated by oxidation of benzene or butane and subjected to rapid cooling is fed into an absorption tower from the bottom, an alcohol absorbent containing an esterification catalyst is sprayed from the top of the tower, and the maleic anhydride gas stream and the absorbent are operated in countercurrent, and an absorption esterification liquid containing maleic acid ester is obtained by spraying absorption or bubbling absorption;

[0028] The process conditions are as follows: the absorption tower adopts a spray absorption tower or a bubbling absorption tower, the temperature of the maleic anhydride gas flow is 70-180°C and the pressure is 0.11-1.00 MPa, the temperature of the alcohol absorbent is 45-90°C, the concentration of the esterification catalyst in the absorbent is 0.0005-0.05wt%, the residence time of the absorbent is 0.50-5.00h, and the temperature of the absorption liquid is 60-150°C; preferably, the temperature of the maleic anhydride gas flow is 80-150°C and the pressure is 0.13-0.75 MPa, the temperature of the alcohol absorbent is 5 0~85℃, the esterification catalyst concentration in the absorbent is 0.001~0.02wt%, the absorbent residence time is 0.75~3.00h, and the absorption liquid temperature is 70~135℃; more preferably, the maleic anhydride gas flow temperature is 90~135℃ and the pressure is 0.15~0.50MPa, the alcohol absorbent temperature is 55~80℃, the esterification catalyst concentration in the absorbent is 0.005~0.01wt%, the absorbent residence time is 1.00~2.00h, and the absorption liquid temperature is 80~120℃.

[0029] The present invention is further configured that the maleic acid monoester or / and diester for double bond selective hydrogenation is selected from purified maleic acid monoester or / and diester, or maleic anhydride esterification product that has not been separated and purified, and the hydrogenation reactor used for the hydrogenation reaction is a slurry bed reactor or a fixed bed reactor;

[0030] When the hydrogenation reactor is an intermittent reactor or a continuous slurry bed reactor, the specific operation includes the following process: the esterification reaction liquid of the esterification reaction of liquid or solid maleic anhydride and alcohol or the absorption esterification liquid of gaseous crude maleic anhydride is fed into the hydrogenation reactor as the feed liquid, and the double bond hydrogenation reaction is carried out in the presence of a supported metal powder hydrogenation catalyst to prepare succinate; the hydrogenation reaction process conditions are: feed temperature 50-150°C, hydrogen pressure 0.2-5.0MPa, hydrogen to feed double bond molar ratio 2-50, interval The intermittent reaction time or the continuous reaction residence time is 0.2 to 10.0 h; preferably, the feed temperature is 55 to 120 ° C, the hydrogen pressure is 0.5 to 3.0 MPa, the molar ratio of hydrogen to feed double bonds is 5 to 30, and the intermittent reaction time or the continuous reaction residence time is 0.4 to 4.0 h; more preferably, the feed temperature is 60 to 90 ° C, the hydrogen pressure is 1.0 to 2.0 MPa, the molar ratio of hydrogen to feed double bonds is 10 to 20, and the intermittent reaction time or the continuous reaction residence time is 0.5 to 2.0 h;

[0031] Alternatively, when a continuous fixed-bed hydrogenation reactor is used, the specific operation includes the following process: the esterification reaction liquid of maleic anhydride and alcohol esterification reaction or the absorption esterification liquid of gaseous crude maleic anhydride is fed into a fixed-bed reactor, and double bonds are hydrogenated to prepare succinate in the presence of a supported metal particle hydrogenation catalyst; the hydrogenation reaction process is: the feed liquid and hydrogen enter the fixed-bed reactor in parallel or countercurrent, the feed temperature is 50-150°C, the hydrogen pressure is 0.2-5.0MPa, the molar ratio of hydrogen to feed double bonds is 2-50, and the feed liquid weight hourly space velocity is 0.10-5.00h -1 Preferably, a trickle bed reactor is used, and the feed liquid and hydrogen are fed in parallel from the top of the reactor, or a bubbling bed reactor is used, and the feed liquid is fed from the top of the reactor and the hydrogen is fed in countercurrent from the bottom or the feed liquid and hydrogen are fed in parallel from the bottom of the reactor, the feed temperature is 55-120°C, the hydrogen pressure is 0.5-3.0MPa, the molar ratio of hydrogen to feed double bonds is 5-30, and the feed liquid weight hourly space velocity is 0.25-2.5h -1 More preferably, a trickle bed reactor is used, the feed liquid and hydrogen are fed in parallel from the top of the reactor, the feed temperature is 60-90°C, the hydrogen pressure is 1.0-2.0 MPa, the molar ratio of hydrogen to feed double bonds is 10-20, and the feed liquid weight hourly space velocity is 0.5-2.0 h -1 .

[0032] The present invention is further configured that the esterification reaction and the hydrogenation reaction are coupled in one step to prepare succinate, which specifically includes the following process: maleic anhydride, alcohol and esterification catalyst are mixed in a stoichiometric ratio and heated to dissolve, and then sent to an esterification-hydrogenation intermittent reactor or a continuous slurry bed reactor to form a slurry with a supported metal powder hydrogenation catalyst, or sent to a fixed bed esterification-hydrogenation reactor filled with a supported metal particle hydrogenation catalyst to carry out maleic anhydride esterification-hydrogenation coupling reaction to prepare succinate; the materials after the reaction are separated into gas and liquid, and the hydrogen is recycled, and the liquid materials of the intermittent reactor or continuous slurry bed reaction are filtered or centrifuged to recover the hydrogenation catalyst and then sent to a separation and refining system, and the liquid materials of the fixed bed reaction are directly sent to a separation and refining system; or,

[0033] The esterification reaction and the hydrogenation reaction are connected in two steps in series to prepare succinic acid ester, which specifically includes the following process: maleic anhydride, alcohol and esterification catalyst are mixed uniformly according to the stoichiometric ratio and heated to dissolve, and then sent to an intermittent or continuous kettle reactor with or without an internal reflux condensing device, or sent to a tubular reactor, and the esterification reaction is carried out to obtain an esterification liquid containing maleic acid ester; then the esterification liquid is directly sent to an intermittent kettle or continuous slurry bed hydrogenation reactor, and forms a slurry with a supported metal powder hydrogenation catalyst, and an intermittent or continuous double bond hydrogenation reaction is carried out to prepare succinic acid ester, and the materials after the reaction are separated from gas and liquid, and the hydrogen is recycled, and the liquid is filtered or centrifuged to recover the hydrogenation catalyst and then sent to a separation and refining system; or, the esterification liquid is directly sent to a fixed bed hydrogenation reactor filled with a supported metal particle catalyst, and double bond hydrogenation is carried out to prepare succinic acid ester, and the materials after the reaction are separated from gas and liquid, and the hydrogen is recycled, and the liquid is sent to a separation and refining system.

[0034] The present invention is further configured that the esterification reaction and the hydrogenation reaction are coupled in one step to prepare succinate. When an intermittent kettle type or a continuous slurry bed reactor is selected, the specific operation includes the following process: the maleic anhydride esterification-hydrogenation coupling reaction raw material liquid, including maleic anhydride, alcohol and esterification catalyst, is fed into the hydrogenation reactor as a feed liquid, and the maleic anhydride continuous esterification-hydrogenation coupling reaction is carried out in the presence of a supported metal powder hydrogenation catalyst; the reaction process conditions are: feed temperature 50-150°C, hydrogen pressure 0.2-5.0MPa, hydrogen and feed Preferably, the feed temperature is 55-120°C, the hydrogen pressure is 0.5-3.0 MPa, the hydrogen to feed double bond molar ratio is 5-30, the intermittent reaction time or the continuous reaction residence time is 0.4-4.0 h; more preferably, the feed temperature is 60-90°C, the hydrogen pressure is 1.0-2.0 MPa, the hydrogen to feed double bond molar ratio is 10-20, the intermittent reaction time or the continuous reaction residence time is 0.5-2.0 h;

[0035] Alternatively, when a continuous fixed-bed hydrogenation reactor is used, the specific operation includes the following process: the raw material liquid of maleic anhydride esterification-hydrogenation coupling reaction, including maleic anhydride, alcohol and esterification catalyst, is fed into the fixed-bed reactor as feed liquid, and maleic anhydride is continuously esterified-hydrogenated coupling reaction is carried out in the presence of a supported metal particle hydrogenation catalyst to prepare succinate, and the reaction process is: the feed liquid and hydrogen enter the fixed-bed reactor in parallel or countercurrent, the feed temperature is 50-150° C., the hydrogen pressure is 0.2-5.0 MPa, the molar ratio of hydrogen to feed double bonds is 2-50, and the feed liquid weight hourly space velocity is 0.10-5.00 h -1 Preferably, a trickle bed reactor is used, and the feed liquid and hydrogen are fed in parallel from the top of the reactor, or a bubbling bed reactor is used, and the feed liquid is fed from the top of the reactor and the hydrogen is fed in countercurrent from the bottom or the feed liquid and hydrogen are fed in parallel from the bottom of the reactor, the feed temperature is 55-120°C, the hydrogen pressure is 0.5-3.0MPa, the molar ratio of hydrogen to feed double bonds is 5-30, and the feed liquid weight hourly space velocity is 0.25-2.5h -1 More preferably, a trickle bed reactor is used, the feed liquid and hydrogen are fed in parallel from the top of the reactor, the feed temperature is 60-90°C, the hydrogen pressure is 1.0-2.0 MPa, the molar ratio of hydrogen to feed double bonds is 10-20, and the feed liquid weight hourly space velocity is 0.5-2.0 h -1 .

[0036] The present invention is further configured that when a slurry bed reactor is used for hydrogenation reaction, the amount of the hydrogenation catalyst is 1.0 to 5.0 wt% of the total amount of maleic anhydride and alcohol, for example, 1.0 wt%, 2.0 wt% or 3.0 wt%.

[0037] In the technical solution of the present invention, the alcohol in the raw material is used as both the alcohol participating in the esterification reaction and the absorbent for absorbing the alcohol in the esterification reaction.

[0038] The present invention is further configured that the alcohol in the raw material is selected from at least one of aliphatic alcohols, aromatic alcohols, heterocyclic alcohols and substituted alcohols thereof; preferably, selected from C1 to C 22 Fatty monohydric alcohol, dihydric alcohol or polyhydric alcohol, C6~C 20 Aromatic monohydric alcohol, dihydric alcohol or polyhydric alcohol, C3~C 18 Heterocyclic monohydric alcohols or dihydric alcohols, or substituted alcohols thereof;

[0039] More preferably, it is selected from methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, amyl alcohol, isopentanol, tert-amyl alcohol, hexanol, heptanol, octanol, 2-ethylhexanol, nonanol, isononanol, decanol, lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, cyclopentanol, cyclohexanol, methylcyclohexanol, tert-butylcyclohexanol, cyclopentylmethanol, cyclohexylmethanol, cyclohexylpropanol, dicyclohexylmethanol, decahydronaphthol, allyl alcohol, methylallyl alcohol, 2-butenol, 2-pentenol, isopentenol, 2-hexenol, 2-octenol, myrcenol, oleyl alcohol, 3-cyclohexylallyl alcohol, 2-cyclohexenol, propargyl alcohol, 2-Butynol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1,4-butylene glycol, 2-methyl-1,3-propanediol, 1,2-pentanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, glycerol, trimethylolethane, trimethylolpropane, 1,2,6-hexanetriol, erythritol, pentaerythritol, mannitol, sorbitol, butenediol, butynediol, benzyl alcohol, α-phenylethanol, β-phenylethanol, 3-phenylpropanol, p-toluene alcohol, p-tert-butylbenzyl alcohol, p-methoxybenzyl alcohol, o-hydroxybenzyl alcohol, benzhydrol, cinnamyl alcohol, o-phthalic acid alcohol, m-phthalic acid alcohol, p-phthalic acid alcohol, 1,4-naphthalene dimethanol, 2,6-naphthalene dimethanol, 1,8-naphthalene dimethanol, 2,2′-biphenyl dimethanol, 4,4′-biphenyl dimethanol, phenyl glycol, glycidol, 2,3-butylene oxide, furfuryl alcohol, tetrahydrofurfuryl alcohol, 2-pyranol, 2-thiophene ethanol, Nicotinic alcohol, 2-piperidinol, 2,5-furan dimethanol, chloroethanol, dichloroethanol, trichloroethanol, 2-chloropropanol, 3-chloropropanol, 4-chlorobutanol, monofluoromethanol, trifluoromethanol, trifluoroethanol, pentafluoropropanol, heptafluorobutanol, p-chlorobenzyl alcohol, pentafluorobenzyl alcohol, p-nitrobenzyl alcohol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polybutylene glycol, polyvinyl alcohol, polyester polyols, phenoxyethanol, 3-phenoxypropanol, triethanolamine, triisopropanolamine, diethylaminopropanol, N-hydroxyethyl pyrrolidone, glycolic acid, methyl glycolate, lactic acid, methyl lactate, 3-hydroxypropionic acid or 4-hydroxybutyric acid.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] (1) The present invention provides a method for producing succinate esters using maleic anhydride as a raw material, comprising using liquid or solid refined maleic anhydride or gaseous crude maleic anhydride as a raw material, and preparing succinate esters through a one-step coupling reaction of esterification-hydrogenation or a two-step series reaction of esterification and hydrogenation. The esterification catalyst has high reaction efficiency, small usage amount and is easy to separate and recover; the hydrogenation catalyst has mild reaction conditions, high activity selectivity and low metal loading, especially a hydrogenation catalyst using a dual carrier with high specific surface area and high thermal conductivity, which has excellent maleic ester double bond hydrogenation performance.

[0042] (2) The metal hydrogenation catalyst supported on the composite carrier of the porous material and the thermally conductive material provided by the present invention has strong tolerance to raw materials and wide applicability. It has a large specific surface area and high low-temperature and low-pressure catalytic activity, high thermal conductivity and good double bond hydrogenation selectivity, and also has excellent anti-sintering ability and long service life. It can be directly used for the double bond hydrogenation of maleic anhydride esterification reaction liquid without separation or crude maleic ester containing impurities. DETAILED DESCRIPTION

[0043] The present invention is further described below in conjunction with specific embodiments. It should be noted that the embodiments described in this section are only a part of the embodiments of the present invention, not all. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0044] Explanation of symbols: BDO is 1,4-butanediol, PTSA is p-toluenesulfonic acid, TfOH is trifluoromethanesulfonic acid, TFSI is bis(trifluoromethanesulfonyl)imide, MTFSI is bis(trifluoromethanesulfonyl)imide, TBMA-TFSI is tributylmethylammonium bis(trifluoromethanesulfonyl)imide, Py is pyridine, MEP is piperidine, EMI is 1-ethyl-3-methylimidazole, CsHPA is cesium heteropolyacid Cs 2.5 H 0.5 PW 12 O 40 .

[0045] Catalyst Description: All esterification catalysts used in the following examples are commercial products. Among the hydrogenation catalysts, except for 1.0wt% Pd / C, 2.0wt% Pd / C, 3.0wt% Ru / C, 5.0wt% Ru / C and 1.0wt% Pt / C, which are commercial products, the preparation process of other hydrogenation catalysts is as follows:

[0046] Step 1. Prepare an aqueous solution of RuCl3·3H2O, PdCl2, H2PtCl6 or Ni(NO3)2·6H2O;

[0047] Step 2. According to the stoichiometric ratio, the powders of porous material Z1 (including activated carbon, γ-Al2O3, SiO2, HM, HZSM-5 or SBA-15) or Z1 and thermal conductive material Z2 (including graphite, Si or SiC) are placed in a synthesis reactor, and one or two of the aqueous solutions of compounds containing Ru, Pd, Pt or Ni elements prepared in step 1 are used for equal volume impregnation at 40°C for 30 minutes. After evaporation and crushing of the cake, it is calcined at 300°C for 2 hours and 550°C for 5 hours to obtain powder catalysts loaded with 0.5wt% Pd, 1.0wt% Pd, 2.0wt% Ru, 0.3wt% Pt-3.0wtRu, 0.5wt% Pd-2.0wt% Ru, 0.2wt% Pd-5.0wt% Ni (see Tables 2 to 5).

[0048] Step 3. Add 5wt% of methyl cellulose, 2wt% of graphite and an appropriate amount of water to the powder catalyst prepared in step 2, mix well and extrude, then calcine at 300°C for 1h and 500°C for 3h to obtain a granular catalyst with a particle size of 2.2mm and a length of 2.5-3.0mm;

[0049] Step 4: Before use, use hydrogen to reduce the powder catalyst offline and the particle catalyst online in situ, with a hydrogen space velocity of 50h -1 , temperature 220℃ (350℃ for Ni catalyst), reduction time 5h.

[0050] Examples 1 to 6

[0051] Preparation of maleic acid monoester by esterification of commercial maleic anhydride and alcohol (batch or continuous batch reaction)

[0052] According to the conditions shown in Table 1, the commercial maleic anhydride is measured with a molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (1.10 ~ 1.25): (0 ~ 0.0002), and the commercial maleic anhydride is mixed with methanol, ethanol, isopropanol, n-butanol, benzyl alcohol or lauryl alcohol, without or with esterification catalyst methyl trifluoromethanesulfonate, trifluoroacetic acid or PTSA, stirred evenly and heated to dissolve, and then sent to an intermittent reactor to react at a temperature of 70 ~ 85 ° C and a pressure of 0.1 ~ 1.0 MPa for 0.5 ~ 2.0 hours, or sent to a continuous reactor to react at a temperature of 90 ~ 95 ° C, a pressure of 0.15 MPa and a residence time of 1.5 ~ 2.5 hours to obtain an esterification liquid containing maleic acid monoester as the main component. Maleic anhydride conversion rate is 96.3 ~ 100%, and maleic acid monoester selectivity is 96.6 ~ 99.8%. The catalyst, reaction mode and conditions, and reaction results corresponding to each embodiment are listed in Table 1.

[0053] Embodiments 7 to 12

[0054] Preparation of maleic acid diester by esterification of commercial maleic anhydride and alcohol (batch or continuous batch reaction)

[0055] The product maleic anhydride is measured at a molar ratio of maleic anhydride:alcohol:esterification catalyst = 1.00:2.25-2.50:0.01-0.02, and the commercial maleic anhydride is mixed with methanol, ethanol, isopropanol, n-butanol or allyl alcohol and the esterification catalyst 1-ethyl-3-methylimidazole bistrifluoromethanesulfonyl imide salt (EMI-TFSI), trifluoromethanesulfonic acid pyridinium salt (Py-TfOH), piperidine bistrifluoromethanesulfonyl imide salt (MEP-TFSI), tributylmethylammonium bistrifluoromethanesulfonyl imide salt (TBMA-TFSI), PTSA or TfOH, heated and dissolved, and then fed into a kettle reactor with an internal reflux condenser device, and reacted at a temperature of 75-115° C. and a pressure of 0.5-1.0 MPa for 1.5-2.5 hours in an intermittent operation, and reacted at a temperature of 65-75° C., a pressure of 0.5 MPa and a residence time of 2.5 hours in a continuous operation to obtain an esterification liquid mainly containing maleic acid diester. The conversion rate of maleic anhydride was 100%, and the selectivity of maleic diester was 98.5-99.7%. The catalysts, reaction conditions and results corresponding to each example are listed in Table 1.

[0056] Comparative Example 1

[0057] Preparation of dimethyl maleate by esterification of commercial maleic anhydride with methanol (intermittent reaction)

[0058] The commercial maleic anhydride, methanol and 40% sulfuric acid were mixed evenly according to the molar ratio of maleic anhydride: methanol: sulfuric acid = 1.00: 2.50: 0.02, heated and dissolved, and then fed into an intermittent kettle reactor with an internal reflux condenser, and reacted at a temperature of 75°C and a pressure of 1.0 MPa for 2.0 hours to obtain an esterification liquid mainly containing dimethyl maleate. The maleic anhydride conversion rate was 100%, and the dimethyl maleate selectivity was 98.5%.

[0059] Comparative Example 2

[0060] Preparation of methyl maleate by esterification of commercial maleic anhydride with methanol (continuous batch reaction)

[0061] The commercial maleic anhydride and methanol were heated and dissolved in a molar ratio of maleic anhydride:methanol:catalyst = 1.00:2.25:0.050, and then the catalyst WO3 / ZrO2 was added and stirred evenly, and then continuously fed into a kettle reactor with an internal reflux condenser, and reacted at a temperature of 65°C and a pressure of 0.5MPa for 2.5h to obtain a mixed esterification liquid of monomethyl maleate and dimethyl maleate. The maleic anhydride conversion rate was 100%, and the selectivity of monomethyl maleate and dimethyl maleate was 23.5% and 76.5% respectively.

[0062] Embodiments 13 to 16

[0063] Preparation of maleic acid esters by esterification of commercial maleic anhydride and alcohol (continuous tubular reaction)

[0064] The commercial maleic anhydride is measured at a molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: 1.20-2.10: 0.0001-0.02, and the commercial maleic anhydride is mixed with 4-methylcyclohexanol, tetrahydrofurfuryl alcohol, ethylene glycol or 1,4-butanediol and esterification catalyst TFSI respectively, and then heated and dissolved and continuously fed into a tubular reactor, and reacted at a temperature of 105-150° C., a pressure of 0.20-0.75 MPa and a material residence time of 1.0-2.0 h to obtain a mixed esterification liquid. The maleic anhydride conversion rate is 100%, the selectivity of the monoesterification reaction to generate maleic acid monoester is greater than 92.1%, and the selectivity of the diester reaction to generate maleic acid diester is more than 81.6%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 1.

[0065] Examples 17 to 20

[0066] Preparation of maleic acid esters by absorption esterification of gaseous maleic anhydride alcohol (continuous absorption esterification process)

[0067] The maleic anhydride gas stream cooled to 90-120°C is continuously fed into a spray or bubbling absorption tower from the bottom, and an alcohol absorbent containing an esterification catalyst at a temperature of 50-70°C is continuously sprayed from the top of the tower, and an absorption liquid mainly containing maleic diester is obtained through absorption and esterification. Among them, the esterification catalyst is aluminum trifluoromethanesulfonate, copper, ytterbium or neodymium, and the alcohol absorbent is ethylene glycol, 1,4-butanediol, 2-ethylhexanol or hydrocinnamyl alcohol. The absorption conditions are controlled as follows: maleic anhydride: alcohol: esterification catalyst = 1.00: (2.25-2.50): 0.020 (molar ratio), temperature 75-95°C, pressure 0.11MPa and material residence time 2.0h. Maleic anhydride conversion rate is 100%, and maleic diester selectivity is 98.5-99.5%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 1.

[0068] Table 1 Catalysts, reaction conditions and results for the esterification of commercial maleic anhydride and alcohol to prepare maleic esters

[0069]

[0070]

[0071] As can be seen from Examples 1 to 20 in Table 1, whether an intermittent or continuous esterification process is used, a reactor type, a pipeline reactor or a fixed bed reactor is used, or commercial liquid or solid maleic anhydride is used as a raw material or gaseous crude maleic anhydride is used as a raw material to prepare maleic acid monoesters or diesters, organic halogenated carboxylic acids or organic sulfonic acids and their derivatives (such as amides, esters or salts) are used as catalysts, and good results are obtained under low catalyst concentrations (less than 0.5wt%) and mild reaction conditions (temperature 65 to 150°C, pressure 0.1 to 1.0MPa, reaction or residence time 0.5 to 2.5h), with maleic anhydride esterification conversion of 96.3 to 100%, selectivity of monoesterification to generate maleic acid monoesters of 92.1 to 99.8%, and selectivity of diesters to generate maleic acid diesters of 81.6 to 99.7%. By comparing Example 7 with Comparative Example 1 and Example 11 with Comparative Example 2, it can be seen that: when inorganic liquid acid (40% sulfuric acid) is used as catalyst, even when the catalyst dosage is higher and the reaction time is longer, the selectivity of maleic anhydride and methanol diesterification reaction is 98.5%, which is still lower than 99.7% when organic acid (EMI-TFSI) is used as catalyst; when inorganic solid acid (WO3 / ZrO2) is used as catalyst, under the same catalyst dosage and process conditions, the selectivity of dimethyl maleate is 76.5%, which is significantly lower than 98.8% when organic acid (PTSA) is used. Obviously, organic halogenated carboxylic acid or organic sulfonic acid and its derivatives are a class of esterification catalysts with excellent catalytic performance, which are superior to the inorganic acid catalysts used in the prior art.

[0072] Examples 21 to 24

[0073] Preparation of succinate by hydrogenation of maleate (intermittent reaction)

[0074] The maleic anhydride esterification liquid obtained in Examples 1, 7 or 4, 10 (mainly monomethyl maleate, dimethyl maleate or mono-n-butyl maleate, di-n-butyl maleate, respectively) was added to an intermittent reactor hydrogenation reactor equipped with a supported powder catalyst 2.0wt% Pd / C or 1.0wt% Pd / γ-Al2O3, and the maleic ester double bond hydrogenation reaction was carried out for 2 hours at a catalyst addition amount of 2.0wt% maleic anhydride esterification liquid, a hydrogen ester molar ratio of 5, a reaction temperature of 70°C and a hydrogen pressure of 2.0MPa. The maleic ester conversion rate was 100%, and the selectivity of double bond hydrogenation to form succinate (monoester + diester) was 100%. The catalysts, reaction conditions and results corresponding to each example are listed in Table 2.

[0075] Embodiments 25 to 28

[0076] Preparation of succinates by hydrogenation of maleates (continuous slurry bed reaction)

[0077] The maleic anhydride esterification liquid obtained in Example 6, 9, 15 or 16 (mainly monolauryl maleate, diisopropyl maleate, ethylene glycol ester, 1,4-butanediol ester, respectively) was continuously fed into a slurry bed hydrogenation reactor equipped with a supported powder catalyst of 1.0wt% Pt / C, 5.0wt% Ru / C, 0.3wt% Pt-3.0wt% Ru / HM or 0.5wt% Pd / SBA-15, and maleic ester double bond hydrogenation reaction was carried out under the conditions of 2.0wt% of maleic anhydride esterification liquid, hydrogen ester molar ratio of 20, reaction temperature of 80°C, hydrogen pressure of 1.5MPa and material residence time of 2.5h. The maleic ester conversion rate was greater than 98.8%, and the selectivity of double bond hydrogenation to form succinate (monoester + diester) was 100%. The catalysts, reaction conditions and results corresponding to each example are listed in Table 2.

[0078] Examples 29 to 32

[0079] Preparation of succinates by hydrogenation of maleates (continuous fixed bed reaction)

[0080] Purified mono-tert-butyl maleate, di-n-butyl maleate, monoisopropyl maleate or diisopropyl maleate are continuously fed into a trickle bed or bubbling bed hydrogenation reactor loaded with a supported particle catalyst 1.0wt% Pd / γ-Al2O3-graphite, 0.5wt% Pd-2.0wt% Ru / γ-Al2O3-Si, 0.2wt% Pd-5.0wt% Ni / SiO2-SiC or 1.0wt% Pd / SBA-15-Si, and the maleate double bond hydrogenation reaction is carried out at a hydrogen-ester molar ratio of 20, a reaction temperature of 65°C, a hydrogen pressure of 1.0MPa and a material residence time of 1.0h. The maleate conversion rate is 100%, and the selectivity of the double bond hydrogenation to generate succinate (monoester+diester) is greater than 99.5%. The catalyst, reaction conditions and results corresponding to each embodiment are listed in Table 2.

[0081] Comparative Example 3

[0082] Preparation of succinates by hydrogenation of maleates (continuous fixed bed reaction)

[0083] Purified di-n-butyl maleate was continuously fed into a trickle bed hydrogenation reactor filled with CuZnAl granular catalyst, and double bond hydrogenation of di-n-butyl maleate was carried out at a hydrogen-ester molar ratio of 100, a reaction temperature of 100°C, a hydrogen pressure of 5.0 MPa and a material residence time of 5.0 h. The conversion rate of di-n-butyl maleate was 98.6%, and the selectivity of double bond hydrogenation to succinate was 95.2%.

[0084] Embodiments 33 to 36

[0085] Preparation of succinates by hydrogenation of gaseous maleic anhydride absorption liquid (continuous fixed bed reaction)

[0086] The maleic anhydride gas stream cooled to 90°C is sprayed and absorbed by ethylene glycol or triethylene glycol containing catalyst PTSA at 50°C according to maleic anhydride: alcohol: PTSA = 1.00:2.25:0.020 (molar ratio), or the maleic anhydride gas stream cooled to 90°C is bubbled and absorbed by 1,4-butanediol or β-phenylethanol at 50°C according to maleic anhydride: alcohol = 1.00:1.50 (molar ratio), and the absorption liquid temperature is controlled at 65°C and the residence time is 2h; and the absorption liquid is continuously fed into a trickle bed or bubbling bed hydrogenation reactor filled with a granular catalyst of 1.0wt% Pd / HZSM-5, 1.0wt% Pd / HM-SiC, 1.0wt% Pd / SiO2-Si or 1.0wt% Pd / SiO2, and the maleic anhydride absorption liquid is hydrogenated at a hydrogen-to-ester molar ratio of 10, a reaction temperature of 60°C, a hydrogen pressure of 2.0MPa and a material residence time of 1.5h. The conversion rate of maleic acid ester hydrogenation was 100%, and the selectivity of double bond hydrogenation to succinate ester (monoester + diester) was 100%. The catalysts, reaction conditions and results corresponding to each example are listed in Table 2.

[0087] Table 2 Catalysts, process conditions and results for preparing succinates by hydrogenation of maleic acid esters and gaseous maleic anhydride absorption liquid

[0088]

[0089]

[0090] It can be seen from Examples 21 to 36 in Table 2 that, regardless of whether an intermittent or continuous hydrogenation reaction process is adopted, or a kettle or fixed bed reactor is adopted, the catalyst with a porous material as a carrier or a composite of a porous material and a heat conductive material as a carrier to load a precious metal (single metal or double metal active component), the hydrogenation of maleic acid monoester or / and diester to prepare succinic acid monoester or / and diester has excellent low-temperature catalytic activity. Under mild reaction conditions (temperature 60 to 80° C., pressure 1.0 to 2.0 MPa, hydrogen-ester ratio 5 to 20, reaction time 1.0 to 2.5 h), the maleic acid ester hydrogenation conversion rate is greater than 98.8%, and the selectivity of double bond hydrogenation saturation to produce succinic acid ester is greater than 99.5%. By comparing Example 30 and Comparative Example 3, it is found that by using a supported precious metal catalyst Pd-Ru / γ-Al2O3-Si, under very mild process conditions (temperature 65°C, hydrogen pressure 1.0 MPa and hydrogen-ester ratio 20), the di-n-butyl maleate conversion rate and double bond hydrogenation reaction selectivity of both 100% can be achieved. However, the catalyst CuZnAl used in the prior art can achieve a di-n-butyl maleate conversion rate of 98.6% and a double bond hydrogenation selectivity of 95.2% under harsh reaction process conditions (temperature 100°C, hydrogen pressure 5.0 MPa and hydrogen-ester ratio 100) for 5.0 h.

[0091] Embodiments 37 to 40

[0092] Preparation of succinate by esterification-hydrogenation of commercial maleic anhydride (intermittent kettle coupling reaction)

[0093] According to the alcohol-anhydride molar ratio of 1.50 to 2.50, commercial maleic anhydride and methanol, ethanol, isopropanol or n-butanol are added to an intermittent reactor, and an esterification catalyst PTSA with a molar amount of maleic anhydride of 0.2% is added or not added, and heated to dissolve under stirring, and then a hydrogenation catalyst 1.0wt% Pd / C-graphite or 1.0wt% Pd / Al2O3-Si with a total feed amount of maleic anhydride and alcohol is added, and after stirring evenly, the maleic anhydride intermittent esterification-hydrogenation coupling reaction is carried out for 2.5 to 4.0 hours at a hydrogen anhydride molar ratio of 10, a temperature of 75 to 85°C, and a hydrogen pressure of 1.0 to 2.0MPa. The maleic anhydride esterification conversion rate is 100%, the maleic anhydride double bond hydrogenation conversion rate is 100%, the succinic acid monoester selectivity of the monoesterification reaction is 100%, and the succinic acid diester selectivity of the diester reaction is 86.3 to 88.5%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 3.

[0094] Embodiments 41 to 44

[0095] Preparation of succinates by esterification-hydrogenation of commercial maleic anhydride (continuous slurry bed coupling reaction)

[0096] The commercial maleic anhydride and alcohol, esterification catalyst TfOH and hydrogenation catalyst are mixed according to the molar ratio of maleic anhydride: alcohol: TfOH = 1.00: 1.25-2.25: 0-0.020 and the amount of hydrogenation catalyst is 2.0wt% of the total amount of maleic anhydride and alcohol, heated and stirred to make slurry, and then continuously fed into a slurry bed reactor, and maleic anhydride continuous esterification-hydrogenation coupling reaction is carried out at a hydrogen anhydride molar ratio of 20, a temperature of 80°C, a hydrogen pressure of 1.0-1.5MPa and a liquid phase material residence time of 2.0-2.5h. Wherein, the alcohol is methanol, ethanol, isopropanol or n-butanol, and the hydrogenation catalyst is 1.0wt% Pd / SiO2-Si, 1.0wt% Pd / HM-SiC or 1.0wt% Pd / SBA-15-Si. The maleic anhydride esterification conversion rate was 100%, the maleic anhydride double bond hydrogenation conversion rate was 100%, the succinic acid monoester selectivity of the monoesterification reaction was 100%, and the succinic acid diester selectivity of the diester reaction was 84.8-85.6%. The catalysts, reaction conditions and results corresponding to each example are listed in Table 3.

[0097] Embodiments 45 to 52

[0098] Preparation of succinate by esterification-hydrogenation of commercial maleic anhydride (continuous fixed bed coupling reaction)

[0099] The commercial maleic anhydride, alcohol and esterification catalyst are mixed and heated to dissolve in a molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: 1.15-2.50: 0-0.020, and then continuously fed into a fixed bed reactor to carry out maleic anhydride continuous esterification-hydrogenation coupling reaction at a hydrogen anhydride molar ratio of 15-20, a temperature of 65-90° C., a hydrogen pressure of 1.0-2.0 MPa and a liquid phase material residence time of 1.0-2.5 h. Wherein, the alcohol is methanol, ethanol, n-butanol, ethylene glycol or 1,4-butanediol, the esterification catalyst is TFSI or its aluminum, scandium or samarium salt, and the hydrogenation catalyst is 1.0wt% Pd / SiO2-Si, 1.0wt% Pd / SiO2-SiC, 1.0wt% Pd / Al2O3-SiC or 1.0wt% Pd / Al2O3-Si. The maleic anhydride esterification conversion rate is 100%, the maleic anhydride double bond hydrogenation conversion rate is 100%, the succinic acid monoester selectivity of the monoesterification reaction is greater than 98.5%, and the succinic acid diester selectivity of the diester reaction is 81.4-85.8%. The catalysts, reaction conditions and results corresponding to each example are listed in Table 3.

[0100] Table 3 Catalysts, process conditions and results for one-step preparation of succinates by commercial maleic anhydride esterification-hydrogenation coupling reaction

[0101]

[0102]

[0103] From the catalysts, process conditions and results of the one-step preparation of succinates by the esterification-hydrogenation coupling reaction of maleic anhydride and alcohol in Examples 37-52 in Table 3, it can be seen that, whether an intermittent or continuous reaction process is adopted, or a kettle or fixed bed reactor is adopted, with or without the addition of an organic liquid acid esterification catalyst, a series of hydrogenation catalysts using a composite of a porous material and a heat conductive material as a carrier to load Pd have excellent catalytic activity for the esterification-hydrogenation coupling reaction of maleic anhydride to prepare succinate monoesters or / and diesters, and under mild reaction conditions (temperature 65-90°C, alcohol-anhydride ratio 1.15-2.5) 0, hydrogen anhydride ratio of 10 to 20, hydrogen pressure of 1.0 to 2.0 MPa) for 1.0 to 4.0 h, the maleic anhydride esterification conversion rate and double bond hydrogenation conversion rate both reached 100%, the selectivity of maleic anhydride monoesterification-hydrogenation reaction to generate succinic acid monoester without adding organic acid catalyst was 98.5 to 100%, and the selectivity of succinic acid ester (the sum of monoester and diester) was 100%; the selectivity of maleic anhydride diesterification-hydrogenation reaction to generate succinic acid diester with the addition of organic acid catalyst was 81.4 to 88.5%, and the selectivity of succinic acid ester (the sum of monoester and diester) was 99.6 to 100%. Obviously, the composite catalyst system composed of organic sulfonic acid or its imine metal salt and Pd-loaded composite carrier hydrogenation catalyst has excellent catalytic activity for the esterification-hydrogenation coupling reaction of maleic anhydride and alcohol to synthesize succinic acid ester.

[0104] Embodiments 53 to 56

[0105] Preparation of succinates by esterification and hydrogenation of commercial maleic anhydride (continuous kettle-kettle series reaction)

[0106] The molar ratio of maleic anhydride:alcohol is 1.00:1.50 or maleic anhydride:alcohol:PTSA is 1.00:2.50:0.02. Commercial maleic anhydride and alcohol or alcohol and esterification catalyst PTSA are mixed and heated to dissolve, and then continuously fed into a kettle reactor to carry out maleic anhydride ring-opening esterification reaction at a temperature of 80-90° C., a pressure of 0.5-1.0 MPa and a residence time of 1.0-2.0 h to obtain an esterified liquid; the esterified liquid is directly fed into a slurry bed reactor and formed into a slurry with a supported metal powder hydrogenation catalyst, and double bond hydrogenation reaction is carried out at a hydrogenation catalyst dosage of 2.0 wt% of the total amount of maleic anhydride and alcohol, a hydrogen anhydride molar ratio of 10-20, a temperature of 60-65° C., a hydrogen pressure of 1.0-2.0 MPa and a residence time of 1.0-2.0 h; the materials after the reaction are separated into gas and liquid, the hydrogen is recycled, and the liquid is filtered to recover the hydrogenation catalyst and then fed into a separation and refining system. Wherein, the alcohol is methanol, ethanol, n-propanol or n-butanol, and the hydrogenation catalyst is 2.0wt% Pd / C or 1.0wt% Pd / Al2O3-Si. The maleic anhydride esterification conversion rate is 100%, the maleic anhydride double bond hydrogenation conversion rate is 100%, the monoesterification reaction succinic acid monoester selectivity is greater than 99.8%, and the diesterization reaction succinic acid diester selectivity is greater than 93.5%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 4.

[0107] Examples 57 to 60

[0108] Preparation of succinates by esterification and hydrogenation of commercial maleic anhydride (continuous tube-tank series reaction)

[0109] The method comprises the following steps: measuring the molar ratio of maleic anhydride:alcohol=1.00:1.25 or maleic anhydride:alcohol:TfOH=1.00:2.25:0.01, mixing commercial maleic anhydride with alcohol or alcohol and esterification catalyst TfOH, heating and dissolving the mixture, and then continuously feeding the mixture into a tubular reactor to perform maleic anhydride ring-opening esterification reaction at a temperature of 60-80°C, a pressure of 0.1-0.5 MPa and a residence time of 2.0-2.5 h to obtain an esterified liquid; directly feeding the esterified liquid into a slurry bed reactor and forming a slurry with a supported metal powder hydrogenation catalyst, performing a double bond hydrogenation reaction at a hydrogenation catalyst dosage of 2.0 wt% of the total amount of maleic anhydride and alcohol, a hydrogen anhydride molar ratio of 10-20, a temperature of 60-80°C, a hydrogen pressure of 1.0-1.5 MPa and a residence time of 1.0-2.0 h; separating the materials after the reaction by gas-liquid separation, recycling the hydrogen, filtering and recovering the hydrogenation catalyst, and then feeding the liquid into a separation and refining system. Wherein, the alcohol is n-propanol, n-butanol, methanol or ethanol, and the hydrogenation catalyst is 1.0wt% Pd / SiO2-Si, 1.0wt% Pd / HM-SiC or 1.0wt% Pd / SBA-15-Si. The maleic anhydride esterification conversion rate is 100%, the maleic anhydride double bond hydrogenation conversion rate is 100%, the monoesterification reaction succinic acid monoester selectivity is greater than 99.2%, and the diesterification reaction succinic acid diester selectivity is greater than 87.7%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 4.

[0110] Embodiments 61 to 64

[0111] Preparation of succinates by esterification and hydrogenation of commercial maleic anhydride (continuous kettle-bed series reaction)

[0112] The commercial maleic anhydride and alcohol or alcohol and esterification catalyst TFSI are mixed and heated to dissolve in a molar ratio of maleic anhydride:alcohol=1.00:1.15 or maleic anhydride:alcohol:TFSI=1.00:2.05:0.02, and then continuously fed into a kettle reactor to carry out maleic anhydride ring-opening esterification reaction at a temperature of 65-85°C, a pressure of 0.1-0.5 MPa and a residence time of 1.0-2.0 h to obtain an esterified liquid; the esterified liquid is directly fed into a trickle bed reactor loaded with a supported metal particle catalyst to carry out a double bond hydrogenation reaction at a hydrogen anhydride molar ratio of 10-20, a temperature of 60-80°C, a hydrogen pressure of 1.0-2.0 MPa and a residence time of 1.0-2.0 h; the reacted materials are separated into gas and liquid, the hydrogen is recycled, and the liquid is fed into a separation and refining system. Wherein, the alcohol is ethylene glycol, 1,4-butanediol (BDO), methanol or ethanol, and the hydrogenation catalyst is 1.0wt% Pd / SiO2-Si, 1.0wt% Pd / Al2O3-SiC or 1.0wt% Pd / SiO2-SiC. The maleic anhydride esterification conversion rate is 100%, the maleic anhydride double bond hydrogenation conversion rate is 100%, the monoesterification reaction succinic acid monoester selectivity is greater than 97.8%, and the diesterization reaction succinic acid diester selectivity is greater than 85.6%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 4.

[0113] Comparative Example 4

[0114] Preparation of succinates by esterification and hydrogenation of commercial maleic anhydride (continuous kettle-bed series reaction)

[0115] The commercial maleic anhydride and methanol were mixed and heated to dissolve at a molar ratio of maleic anhydride:methanol = 1.00:2.05, and the catalyst SO4 was added. 2- / ZrO2 and stirred evenly, the mixture was continuously fed into a kettle reactor, and maleic anhydride ring-opening esterification reaction was carried out at a temperature of 65°C, a pressure of 0.5MPa and a residence time of 2.0h to obtain an esterified liquid; the esterified liquid was then directly fed into a trickle bed reactor filled with 1.0wt% Pd / SiO2-Si granular catalyst, and double bond hydrogenation reaction was carried out at a hydrogen anhydride molar ratio of 15, a temperature of 60°C, a hydrogen pressure of 2.0MPa and a residence time of 2.0h. The maleic anhydride esterification conversion rate was 100%, the maleic anhydride double bond hydrogenation conversion rate was 100%, the monomethyl succinate selectivity was 22.5%, and the dimethyl succinate selectivity was 77.5%.

[0116] From the catalysts, process conditions and results of the esterification and hydrogenation series reaction of maleic anhydride and alcohol to prepare succinate esters in Examples 53 to 64 in Table 4, it can be found that the continuous kettle-kettle series, tube-kettle series or kettle-bed series reaction process is adopted, and the metal Pd supported by a porous carrier or a composite carrier of a porous material and a heat-conducting material is used as a hydrogenation catalyst. For the maleic anhydride monoesterification product without a catalyst and the maleic anhydride diesterification reaction product with the addition of an organic liquid acid catalyst, both have good double bond hydrogenation performance. Under the esterification reaction conditions and temperature of 60 to 90° C., 0.1 to 1.0 MPa, an alcohol-anhydride ratio of 1.15 to 2.50, and a material residence time of 1.0 to 2.5 h, the esterification reaction conditions and temperature are as follows: Under the conditions of hydrogenation reaction of 60-80°C, hydrogen anhydride ratio of 10-20, hydrogen pressure of 1.0-2.0MPa, and residence time of esterification product of 1.0-2.0h, the esterification conversion rate of maleic anhydride and the double bond hydrogenation conversion rate both reach 100%, and the selectivity of maleic anhydride monoesterification and hydrogenation tandem reaction to generate succinic acid monoester is 97.8-99.9% without adding organic acid catalyst, and the total selectivity of succinic acid ester (the sum of monoester and diester) is 99.2-99.9%; the selectivity of maleic anhydride diesterification and hydrogenation tandem reaction to generate succinic acid diester is 85.6-94.5%, and the total selectivity of succinic acid ester (the sum of monoester and diester) is 100%. Comparing Example 63 with Comparative Example 4, it can be seen that under the same esterification and hydrogenation reaction conditions and the same hydrogenation catalyst, the inorganic solid superacid SO4 used in the prior art can be used to obtain the ester of maleic anhydride. 2- / ZrO2 was used as the catalyst for the esterification of maleic anhydride and methanol, and the selectivity of dimethyl succinate was 77.5%, which was significantly lower than 85.6% when bistrifluoromethanesulfonyl imide (TFSI) was used as the esterification catalyst. It can be seen that organic sulfonic acid or its imine has good catalytic activity for the diesterification reaction of acid anhydride and the Pd-loaded hydrogenation catalyst for the double bond hydrogenation reaction of maleic acid monoester / diester.

[0117] Table 4 Catalysts, process conditions and results for preparing succinates by esterification and hydrogenation of commercial maleic anhydride in series

[0118]

[0119] Embodiments 65 to 68

[0120] Preparation of succinates by absorption esterification and hydrogenation of gaseous maleic anhydride (continuous tower-kettle series process)

[0121] The maleic anhydride gas stream rapidly cooled to 90°C is continuously fed into a spray absorption tower from the bottom, and n-hexanol or cyclohexanol absorbent at a temperature of 50°C is continuously sprayed from the top of the tower, and maleic anhydride:alcohol=1.00:1.50 or maleic anhydride:alcohol:esterification catalyst PTSA=1.00:2.50:0.020 (molar ratio), the absorption liquid temperature is about 75°C, and the material residence time is 2.0h, to obtain an absorption esterification liquid; the esterification liquid is directly fed into a slurry bed reactor and formed into a slurry with a supported metal powder hydrogenation catalyst, and a double bond hydrogenation reaction is carried out under the conditions of a hydrogenation catalyst dosage of 2.0wt% of the total amount of maleic anhydride and alcohol, a hydrogen anhydride molar ratio of 20, a temperature of 65°C, a hydrogen pressure of 1.0MPa, and a residence time of 2.0h; the reacted material is separated into gas and liquid, the hydrogen is recycled, and the liquid is filtered to recover the hydrogenation catalyst and then fed into a separation and refining system. Wherein, the hydrogenation catalyst is 1.0wt% Pd / C or 1.0wt% Pd / Al2O3-Si. The maleic anhydride esterification conversion rate is 100%, the double bond hydrogenation conversion rate is 100%, and the selectivity of double bond hydrogenation to generate succinate (monoester + diester) is 100%, wherein the selectivity of monoesterified succinic acid monoester is greater than 99.7%, and the selectivity of diesterified succinic acid diester is greater than 98.3%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 5.

[0122] Embodiments 69 to 72

[0123] Preparation of succinates by absorption esterification and hydrogenation of gaseous maleic anhydride (continuous tower-bed series process)

[0124] The maleic anhydride gas stream cooled to 120°C is continuously fed into a bubbling absorption tower from the bottom, and benzyl alcohol or cyclohexyl methanol absorbent at a temperature of 60°C is continuously sprayed from the top of the tower, and maleic anhydride: alcohol = 1.00: 1.25 or maleic anhydride: alcohol: esterification catalyst TfOH = 1.00: 2.25: 0.020 (molar ratio), the absorption liquid temperature is about 85°C, and the material residence time is 1.5h, to obtain an absorption esterification liquid; the esterification liquid is directly fed into a trickle bed reactor loaded with a supported metal particle catalyst, and a double bond hydrogenation reaction is carried out at a hydrogen anhydride molar ratio of 10, a temperature of 65°C, a hydrogen pressure of 2.0MPa, and a residence time of 1.5h. The reacted material is separated by gas and liquid, the hydrogen is recycled, and the liquid is fed into a separation and refining system. Wherein, the hydrogenation catalyst is 1.0wt% Pd / SiO2-Si, 1.0wt% Pd / HM-SiC or 1.0wt% Pd / HZSM-5-Si. The maleic anhydride esterification conversion rate was 100%, the double bond hydrogenation conversion rate was 100%, and the selectivity of double bond hydrogenation to generate succinate (monoester + diester) was 99.9%, wherein the selectivity of monoesterified succinic acid monoester was greater than 99.3%, and the selectivity of diesterified succinic acid diester was greater than 98.9%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 5.

[0125] Embodiments 73 to 76

[0126] Preparation of succinates by absorption esterification and hydrogenation of gaseous maleic anhydride (continuous bed-bed series process)

[0127] The maleic anhydride gas stream rapidly cooled to 120°C is continuously fed from the bottom into a bubbling bed filled with SiC ceramic ball fillers, and is continuously sprayed with ethylene glycol or 1,4-butanediol absorbent at a temperature of 55°C, and the maleic anhydride:alcohol=1.00:1.50 or maleic anhydride:alcohol:esterification catalyst TFSI=1.00:2.50:0.020 (molar ratio), the absorption liquid temperature is about 80°C, and the material residence time is 1.0h, to obtain an absorption esterification liquid; the esterification liquid is directly fed into a bubbling bed reactor filled with a supported metal particle catalyst, and a double bond hydrogenation reaction is carried out at a hydrogen anhydride molar ratio of 15, a temperature of 70°C, a hydrogen pressure of 1.5MPa, and a residence time of 1.0h. The reacted material is separated into gas and liquid, the hydrogen is recycled, and the liquid is fed into a separation and refining system. Wherein, the hydrogenation catalyst is 1.0wt% Pd / SiO2-Si, 1.0wt% Pd / Al2O3-SiC or 1.0wt% Pd / SiO2-SiC. The maleic anhydride esterification conversion rate is 100%, the double bond hydrogenation conversion rate is 100%, and the double bond hydrogenation generates succinate (monoester + diester) selectivity 99.9%, wherein the monoesterification succinate monoester selectivity is greater than 99.4%, and the diesterification succinate diester selectivity is greater than 98.5%. The catalysts, reaction conditions and results corresponding to each embodiment are listed in Table 5.

[0128] Table 5 Catalysts, process conditions and results for preparing succinates by tandem reaction of gaseous maleic anhydride absorption esterification and double bond hydrogenation

[0129]

[0130] From the catalyst, process conditions and results of preparing succinate esters by gaseous maleic anhydride absorption esterification and hydrogenation reaction in series in Examples 65 to 76 in Table 5, it can be seen that whether the continuous spray absorption esterification tower-slurry bed (kettle) hydrogenation series process and the bubbling absorption esterification tower-trickle bed hydrogenation series process or the bubbling absorption esterification bed-bubbling bed hydrogenation series process is adopted, the metal Pd supported by a porous carrier or a composite carrier of a porous material and a heat-conducting material is used as a hydrogenation catalyst. For the maleic anhydride monoesterification product that does not require a catalyst and the maleic anhydride diesterification reaction product with the addition of an organic liquid acid catalyst, both have excellent double bond hydrogenation activity, and at a temperature of 75 to 85° C., an alcohol-anhydride ratio of 1.25 to 2.50, an absorbent residence time of 1.0 Under the conditions of absorption esterification of 65 to 70°C, hydrogen anhydride ratio of 10 to 20, hydrogen pressure of 1.0 to 2.0 MPa, and absorption liquid residence time of 1.0 to 2.0 h, the conversion rate of maleic anhydride esterification and double bond hydrogenation conversion rate both reached 100%, and the selectivity of maleic anhydride monoesterification and hydrogenation tandem reaction to generate succinic acid monoester was 99.3 to 99.8%, and the total selectivity of succinic acid ester (the sum of monoester and diester) was greater than 99.9%; the selectivity of maleic anhydride diesterification and hydrogenation tandem reaction to generate succinic acid diester was 98.3 to 99.1%, and the total selectivity of succinic acid ester (the sum of monoester and diester) was greater than 99.9% when the organic acid catalyst was added. Therefore, organic sulfonic acid or its imine has good catalytic activity for the diesterification reaction of gaseous maleic anhydride alcohol absorption liquid and the Pd-loaded hydrogenation catalyst has good catalytic activity for the double bond hydrogenation of gaseous maleic anhydride absorption esterification liquid.

[0131] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for producing succinates from maleic anhydride, characterized in that: The method comprises the following steps: using maleic anhydride and alcohol as raw materials, carrying out an esterification reaction in the presence of an esterification catalyst to prepare maleic acid monoester or / and diester; then, in the presence of a hydrogenation catalyst, selectively hydrogenating double bonds to prepare succinic acid monoester or / and diester, and the esterification reaction and the hydrogenation reaction are carried out in two steps in series or in one step in coupling to prepare succinic acid ester; The esterification catalyst is selected from a halogenated carboxylic acid or anhydride of the structural formula RCOOH or (RCOO)2O, or a halogenated sulfonic acid, alkyl sulfonic acid or halogenated alkyl sulfonic acid or its ester, salt or anhydride of the structural formula R′SO3M or (R′SO2)2O, or a halogenated sulfonic acid of the structural formula [(R″SO2)2N] m M is a dihalogenated sulfonyl imide or a dihalogenated hydrocarbon sulfonyl imide or a salt thereof; R is a halogenated hydrocarbon group, R′ is a halogen, a hydrocarbon group or a halogenated hydrocarbon group, M is hydrogen, a hydrocarbon group or an ammonium, metal, pyridine, piperidine, guanidine, or imidazolium ion, R″ is a halogen or a halogenated hydrocarbon group, and m is an integer from 1 to 4; The hydrogenation catalyst is selected from a supported monometallic or bimetallic catalyst with a structural formula of aA1-bA2 / (cZ1+dZ2), wherein A1 is a first active component noble metal, A2 is a second active component noble metal or transition metal, Z1 is a first carrier porous material, Z2 is a second carrier thermal conductive material, a, b, c and d are respectively the mass fractions of A1, A2, Z1 and Z2 in the catalyst, a=0.01-5.00%, b=0-10.00%, c=50.00-99.99%, d=0-49.99%.

2. A method for producing succinates from maleic anhydride according to claim 1, characterized in that: The esterification catalyst is selected from a halogenated carboxylic acid or anhydride with a structural formula of RCOOH or (RCOO)2O, an alkyl sulfonic acid, aryl sulfonic acid or anhydride with a structural formula of R'SO3H or (R'SO2)2O, or a n F 2n+1 SO2)2O perfluorosulfonic anhydride, or a perfluorosulfonic anhydride of formula C n F 2n+1 SO3M perfluorosulfonic acid or its ester or salt, or the structural formula [(C n F 2n+1 SO2)2N] m M is at least one of a bisperfluorosulfonyl imide or a salt thereof; wherein R is a chlorinated or fluorinated C1-C3 alkyl group, and R′ is a C1-C3 alkyl group or a C6-C 10 Aryl, M is hydrogen, C1-C4 alkyl or ammonium, metal, pyridine, piperidine, guanidine or imidazole ion, n is an integer of 0-4, and m is an integer of 1-4.

3. A method for producing succinates from maleic anhydride according to claim 2, characterized in that: The esterification catalyst is selected from at least one of trichloroacetic acid, trifluoroacetic acid, perfluoropropionic acid, methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid or β-naphthalenesulfonic acid or their anhydrides, or fluorosulfonic acid or trifluoromethanesulfonic acid or their anhydrides or methyl esters or ethyl esters, or bis(trifluoromethanesulfonyl)imide or bis(trifluoromethanesulfonyl)imide, or salts of fluorosulfonic acid, trifluoromethanesulfonic acid, bis(trifluoromethanesulfonyl)imide of Li, Na, K, Ag, Mg, Ca, Sr, Ba, Ni, Cu, Zn, Al, In, Fe, Bi, Zr, Sn or rare earth or pyridine, piperidine, guanidine, imidazolium ions; Preferably, the esterification catalyst is selected from at least one of trifluoroacetic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, fluorosulfonic acid, trifluoromethanesulfonic acid, trifluoromethanesulfonic anhydride, methyl fluorosulfonate, methyl trifluoromethanesulfonate, bis(trifluoromethanesulfonyl)imide, or a salt of Li, Mg, Cu, Zn, Al, In, Fe, Bi, Zr, Sn, Sc, La, Ce, Pr, Nd, Sm, Yb, or pyridine, N-butylpyridine sulfonate, N-alkylpyridine, piperidine, 1-ethyl-2-methylpiperidine, guanidine, imidazole, 1-alkylimidazole, 1-alkyl-3-methylimidazole with fluorosulfonic acid, trifluoromethanesulfonic acid, bis(trifluoromethanesulfonyl)imide or bis(trifluoromethanesulfonyl)imide.

4. A method for producing succinates from maleic anhydride according to claim 1, characterized in that: In the hydrogenation catalyst, A1 is selected from Ru, Os, Rh, Pd or Pt, A2 is selected from Re, Ru, Ir, Cr, Mn, Fe, Co, Ni or Cu; Z1 has a specific surface area greater than 50m 2 / g porous material, selected from at least one of activated carbon, mesoporous carbon, carbon nanotubes, graphene, SiO2, γ-Al2O3, θ-Al2O3, mesoporous Al2O3, SiO2-Al2O3, TiO2, ZrO2, HM, HHEU, Hβ, HZSM-5, HZSM-22, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-56, SBA-15, ZEO-1, ZEO-3 or KIT-6; Z2 is a thermal conductivity greater than 5W / cm 2 The thermally conductive material is selected from graphite, Si, BeO, MgO, α-Al2O3, α-SiO2, ZrO2, BN, AlN, SiC, ZrC, Mo2C, W2C or WC; a=0.05-3.00%, b=0-7.50%, c=55.00-99.95%, d=0-44.95%; Preferably, A1 is Ru, Pd or Pt, A2 is Ru, Co, Ni or Cu, and Z1 is a metal with a specific surface area greater than 100 m 2 / g activated carbon, SiO2, γ-Al2O3, SiO2-Al2O3, TiO2, ZrO2, HM, Hβ, HZSM-5, HMCM-22, HMCM-41 or SBA-15, Z2 is a thermal conductivity greater than 10W / cm 2 Graphite, Si, α-Al2O3, α-SiO2 or SiC, a = 0.10 ~ 2.00%, b = 0 ~ 5.00%, c = 60.00 ~ 99.90%, d = 0 ~ 39.90%; More preferably, A1 is Ru, Pd or Pt, A2 is Ru or Ni, and Z1 is a metal with a specific surface area greater than 200 m 2 / g activated carbon, SiO2, γ-Al2O3, HM, HZSM-5 or SBA-15, Z2 is thermal conductivity greater than 20W / cm 2 Graphite, Si or SiC, a=0.20~1.00%, b=0~5.00%, c=65.00~99.80%, d=0~34.80%.

5. The method for producing succinates from maleic anhydride according to claim 1, characterized in that: The esterification reaction uses liquid maleic anhydride or solid maleic anhydride and alcohol to carry out esterification reaction, or uses alcohol to absorb gaseous maleic anhydride to carry out absorption esterification reaction; When liquid maleic anhydride or solid maleic anhydride is used for esterification reaction with alcohol, the esterification reaction includes the following process: firstly, the product maleic anhydride is mixed with alcohol and esterification catalyst according to the stoichiometric ratio, and heated to dissolve, and then sent to an intermittent or continuous kettle reactor with or without an internal reflux condenser, or sent to a tubular reactor, to carry out esterification reaction, and obtain an esterification reaction liquid containing maleic ester; the process conditions are: raw material molar ratio maleic anhydride: alcohol: esterification catalyst = 1.00: (1.00-10.00): (0-0.001), reaction temperature 50-120°C, reaction pressure 0.10-2.00MPa, intermittent reaction time or continuous reaction residence time 0. 20~5.00h; preferably, the raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (1.02~5.00): (0~0.0005), the reaction temperature is 55~105°C, the reaction pressure is 0.10~1.50MPa, and the intermittent reaction time or the continuous reaction residence time is 0.50~2.50h; more preferably, the raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (1.05~2.00): (0~0.0001), the reaction temperature is 60~90°C, the reaction pressure is 0.10~1.00MPa, and the intermittent reaction time or the continuous reaction residence time is 0.75~1.50h; Alternatively, alcohol is used to absorb gaseous maleic anhydride for absorption esterification reaction, and the absorption esterification comprises the following process: a maleic anhydride gas stream generated by oxidation of benzene or butane which has been quenched is fed from the bottom to an absorption tower, an alcohol absorbent containing an esterification catalyst is sprayed from the top of the tower, the maleic anhydride gas stream and the absorbent are operated in countercurrent, and an absorption esterification liquid containing maleic ester is obtained by spraying absorption or bubbling absorption; the process conditions are: the absorption tower is a spray absorption tower or a bubbling absorption tower, the maleic anhydride gas stream temperature is 55-120°C and the pressure is 0.11-1.00 MPa, the alcohol absorbent temperature is 25-85°C, the esterification catalyst concentration in the absorbent is 0-0.0005wt%, and the absorbent residence time is 0. 20~2.00h, the absorption liquid temperature is 50~90℃; preferably, the maleic anhydride gas flow temperature is 60~105℃ and the pressure is 0.13~0.75MPa, the alcohol absorbent temperature is 35~75℃, the esterification catalyst concentration in the absorbent is 0~0.0002wt%, the absorbent residence time is 0.30~1.50h, and the absorption liquid temperature is 55~85℃; more preferably, the maleic anhydride gas flow temperature is 65~90℃ and the pressure is 0.15~0.50MPa, the alcohol absorbent temperature is 45~65℃, the esterification catalyst concentration in the absorbent is 0~0.0001wt%, the absorbent residence time is 0.50~1.00h, and the absorption liquid temperature is 60~80℃.

6. The method for producing succinates from maleic anhydride according to claim 1, characterized in that: When liquid maleic anhydride or solid maleic anhydride is used to ring-open esterify alcohol to prepare maleic diester, the esterification reaction includes the following process: first, the product maleic anhydride is mixed with alcohol and esterification catalyst according to the stoichiometric ratio, heated and dissolved, and then sent into an intermittent or continuous autoclave reactor with an internal reflux condenser to carry out esterification reaction to obtain an esterification reaction liquid containing maleic acid ester; the process conditions are: raw material molar ratio maleic anhydride: alcohol: esterification catalyst = 1.00: (2.00-10.00): (0.0005-0.10), reaction temperature 70-150° C., reaction pressure 0.1-2.0 MPa, intermittent reaction time or continuous reaction residence time 0.50-1 0.00h; preferably, the raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (2.10-5.00): (0.001-0.05), the reaction temperature is 75-135°C, the reaction pressure is 0.1-1.0MPa, and the intermittent reaction time or the continuous reaction residence time is 0.75-5.00h; more preferably, the raw material molar ratio of maleic anhydride: alcohol: esterification catalyst = 1.00: (2.25-3.00): (0.002-0.02), the reaction temperature is 80-120°C, the reaction pressure is 0.1-0.5MPa, and the intermittent reaction time or the continuous reaction residence time is 1.00-2.50h; Alternatively, maleic acid diester is prepared by alcohol absorption and ring-opening esterification of maleic anhydride gas stream, wherein the esterification reaction comprises the following steps: a maleic anhydride gas stream generated by oxidation of benzene or butane and subjected to rapid cooling is fed into an absorption tower from the bottom, an alcohol absorbent containing an esterification catalyst is sprayed from the top of the tower, and the maleic anhydride gas stream and the absorbent are operated in countercurrent, and an absorption esterification liquid containing maleic acid ester is obtained by spraying absorption or bubbling absorption; The process conditions are as follows: the absorption tower adopts a spray absorption tower or a bubbling absorption tower, the temperature of the maleic anhydride gas flow is 70-180°C and the pressure is 0.11-1.00 MPa, the temperature of the alcohol absorbent is 45-90°C, the concentration of the esterification catalyst in the absorbent is 0.0005-0.05wt%, the residence time of the absorbent is 0.50-5.00h, and the temperature of the absorption liquid is 60-150°C; preferably, the temperature of the maleic anhydride gas flow is 80-150°C and the pressure is 0.13-0.75 MPa, the temperature of the alcohol absorbent is 5 0~85℃, the esterification catalyst concentration in the absorbent is 0.001~0.02wt%, the absorbent residence time is 0.75~3.00h, and the absorption liquid temperature is 70~135℃; more preferably, the maleic anhydride gas flow temperature is 90~135℃ and the pressure is 0.15~0.50MPa, the alcohol absorbent temperature is 55~80℃, the esterification catalyst concentration in the absorbent is 0.005~0.01wt%, the absorbent residence time is 1.00~2.00h, and the absorption liquid temperature is 80~120℃.

7. The method for producing succinates from maleic anhydride according to claim 1, characterized in that: The maleic acid monoester or / and diester for double bond selective hydrogenation is selected from purified maleic acid monoester or / and diester, or maleic anhydride esterification product that has not been separated and purified, and the hydrogenation reactor used for the hydrogenation reaction is a slurry bed reactor or a fixed bed reactor; When the hydrogenation reactor is an intermittent reactor or a continuous slurry bed reactor, the specific operation includes the following process: the esterification reaction liquid of the esterification reaction of liquid or solid maleic anhydride and alcohol or the absorption esterification liquid of gaseous crude maleic anhydride is fed into the hydrogenation reactor as the feed liquid, and the double bond hydrogenation reaction is carried out in the presence of a supported metal powder hydrogenation catalyst to prepare succinate; the hydrogenation reaction process conditions are: feed temperature 50-150°C, hydrogen pressure 0.2-5.0MPa, hydrogen to feed double bond molar ratio 2-50, interval The intermittent reaction time or the continuous reaction residence time is 0.2 to 10.0 h; preferably, the feed temperature is 55 to 120 ° C, the hydrogen pressure is 0.5 to 3.0 MPa, the molar ratio of hydrogen to feed double bonds is 5 to 30, and the intermittent reaction time or the continuous reaction residence time is 0.4 to 4.0 h; more preferably, the feed temperature is 60 to 90 ° C, the hydrogen pressure is 1.0 to 2.0 MPa, the molar ratio of hydrogen to feed double bonds is 10 to 20, and the intermittent reaction time or the continuous reaction residence time is 0.5 to 2.0 h; Alternatively, when a continuous fixed-bed hydrogenation reactor is used, the specific operation includes the following process: the esterification reaction liquid of maleic anhydride and alcohol esterification reaction or the absorption esterification liquid of gaseous crude maleic anhydride is fed into the fixed-bed reactor as the feed liquid, and double bonds are hydrogenated to prepare succinate in the presence of a supported metal particle hydrogenation catalyst; the hydrogenation reaction process is: the feed liquid and hydrogen enter the fixed-bed reactor in parallel or countercurrent, the feed temperature is 50-150°C, the hydrogen pressure is 0.2-5.0MPa, the molar ratio of hydrogen to feed double bonds is 2-50, and the feed liquid weight hourly space velocity is 0.10-5.00h -1 Preferably, a trickle bed reactor is used, and the feed liquid and hydrogen are fed in parallel from the top of the reactor, or a bubbling bed reactor is used, and the feed liquid is fed from the top of the reactor and the hydrogen is fed in countercurrent from the bottom or the feed liquid and hydrogen are fed in parallel from the bottom of the reactor, the feed temperature is 55-120°C, the hydrogen pressure is 0.5-3.0MPa, the molar ratio of hydrogen to feed double bonds is 5-30, and the feed liquid weight hourly space velocity is 0.25-2.5h -1 More preferably, a trickle bed reactor is used, the feed liquid and hydrogen are fed in parallel from the top of the reactor, the feed temperature is 60-90°C, the hydrogen pressure is 1.0-2.0 MPa, the molar ratio of hydrogen to feed double bonds is 10-20, and the feed liquid weight hourly space velocity is 0.5-2.0 h -1 .

8. The method for producing succinates from maleic anhydride according to claim 1, characterized in that: The esterification reaction and the hydrogenation reaction are coupled in one step to prepare succinate, which specifically includes the following process: maleic anhydride, alcohol and esterification catalyst are mixed in a stoichiometric ratio and heated to dissolve, and then sent to an esterification-hydrogenation batch reactor or a continuous slurry bed reactor to form a slurry with a supported metal powder hydrogenation catalyst, or sent to a fixed bed esterification-hydrogenation reactor filled with a supported metal particle hydrogenation catalyst to carry out maleic anhydride esterification-hydrogenation coupling reaction to prepare succinate; the materials after the reaction are separated into gas and liquid, and the hydrogen is recycled, and the liquid materials of the batch reactor or continuous slurry bed reaction are filtered or centrifuged to recover the hydrogenation catalyst and then sent to a separation and refining system, and the liquid materials of the fixed bed reaction are directly sent to a separation and refining system; or, The esterification reaction and hydrogenation reaction are two steps in series to prepare succinate, which specifically includes the following process: Maleic anhydride, alcohol and esterification catalyst are mixed uniformly according to the stoichiometric ratio and heated to dissolve, and then fed into an intermittent or continuous kettle reactor with or without an internal reflux condensing device, or fed into a tubular reactor, to carry out esterification reaction to obtain an esterified liquid containing maleic acid ester; the esterified liquid is then directly fed into an intermittent kettle or continuous slurry bed hydrogenation reactor, and slurried with a supported metal powder hydrogenation catalyst, to carry out an intermittent or continuous double bond hydrogenation reaction to prepare succinic acid ester, the materials after the reaction are subjected to gas-liquid separation, the hydrogen is recycled, the liquid is filtered or centrifuged to recover the hydrogenation catalyst, and then fed into a separation and refining system; or, the esterified liquid is directly fed into a fixed bed hydrogenation reactor filled with a supported metal particle catalyst, to carry out double bond hydrogenation to prepare succinic acid ester, the materials after the reaction are subjected to gas-liquid separation, the hydrogen is recycled, and the liquid is fed into a separation and refining system.

9. The method for producing succinate esters from maleic anhydride according to claim 1, characterized in that: The esterification reaction and the hydrogenation reaction are coupled in one step to prepare succinate. When an intermittent reactor or a continuous slurry bed reactor is used, the specific operation includes the following process: the raw material liquid of the maleic anhydride esterification-hydrogenation coupling reaction, including maleic anhydride, alcohol and esterification catalyst, is fed into the hydrogenation reactor as the feed liquid, and the maleic anhydride continuous esterification-hydrogenation coupling reaction is carried out in the presence of a supported metal powder hydrogenation catalyst; the reaction process conditions are: feed temperature 50-150°C, hydrogen pressure 0.2-5.0MPa, hydrogen and feed double bond molar ratio Ratio 2-50, intermittent reaction time or continuous reaction residence time 0.2-10.0h; preferably, feed temperature 55-120°C, hydrogen pressure 0.5-3.0MPa, hydrogen to feed double bond molar ratio 5-30, intermittent reaction time or continuous reaction residence time 0.4-4.0h; more preferably, feed temperature 60-90°C, hydrogen pressure 1.0-2.0MPa, hydrogen to feed double bond molar ratio 10-20, intermittent reaction time or continuous reaction residence time 0.5-2.0h; Alternatively, when a continuous fixed-bed hydrogenation reactor is used, the specific operation includes the following process: the raw material liquid of maleic anhydride esterification-hydrogenation coupling reaction, including maleic anhydride, alcohol and esterification catalyst, is fed into the fixed-bed reactor as feed liquid, and maleic anhydride is continuously esterified-hydrogenated coupling reaction is carried out in the presence of a supported metal particle hydrogenation catalyst to prepare succinate, and the reaction process is: the feed liquid and hydrogen enter the fixed-bed reactor in parallel or countercurrent, the feed temperature is 50-150° C., the hydrogen pressure is 0.2-5.0 MPa, the molar ratio of hydrogen to feed double bonds is 2-50, and the feed liquid weight hourly space velocity is 0.10-5.00 h -1 Preferably, a trickle bed reactor is used, and the feed liquid and hydrogen are fed in parallel from the top of the reactor, or a bubbling bed reactor is used, and the feed liquid is fed from the top of the reactor and the hydrogen is fed in countercurrent from the bottom or the feed liquid and hydrogen are fed in parallel from the bottom of the reactor, the feed temperature is 55-120°C, the hydrogen pressure is 0.5-3.0MPa, the molar ratio of hydrogen to feed double bonds is 5-30, and the feed liquid weight hourly space velocity is 0.25-2.5h -1 More preferably, a trickle bed reactor is used, the feed liquid and hydrogen are fed in parallel from the top of the reactor, the feed temperature is 60-90°C, the hydrogen pressure is 1.0-2.0 MPa, the molar ratio of hydrogen to feed double bonds is 10-20, and the feed liquid weight hourly space velocity is 0.5-2.0 h -1 .

10. The method for producing succinate esters from maleic anhydride according to claim 1, characterized in that: The alcohol in the raw material is selected from at least one of aliphatic alcohols, aromatic alcohols, heterocyclic alcohols and substituted alcohols thereof; preferably, selected from C1 to C 22 Fatty monohydric alcohol, dihydric alcohol or polyhydric alcohol, C6~C 20 Aromatic monohydric alcohol, dihydric alcohol or polyhydric alcohol, C3~C 18 Heterocyclic monohydric alcohols or dihydric alcohols, or substituted alcohols thereof; More preferably, it is selected from methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, amyl alcohol, isopentanol, tert-amyl alcohol, hexanol, heptanol, octanol, 2-ethylhexanol, nonanol, isononanol, decanol, lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, cyclopentanol, cyclohexanol, methylcyclohexanol, tert-butylcyclohexanol, cyclopentylmethanol, cyclohexylmethanol, cyclohexylpropanol, dicyclohexylmethanol, decahydronaphthol, allyl alcohol, methylallyl alcohol, 2-butenol, 2-pentenol, isopentenol, 2-hexenol, 2-octenol, myrcenol, oleyl alcohol, 3-cyclohexylallyl alcohol, 2-cyclohexenol, propargyl alcohol, 2-Butynol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1,4-butylene glycol, 2-methyl-1,3-propanediol, 1,2-pentanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, glycerol, trimethylolethane, trimethylolpropane, 1,2,6-hexanetriol, erythritol, pentaerythritol, mannitol, sorbitol, butenediol, butynediol, benzyl alcohol, α-phenylethanol, β-phenylethanol, 3-phenylpropanol, p-toluene alcohol, p-tert-butylbenzyl alcohol, p-methoxybenzyl alcohol, o-hydroxybenzyl alcohol, benzhydrol, cinnamyl alcohol, o-phthalic acid alcohol, m-phthalic acid alcohol, p-phthalic acid alcohol, 1,4-naphthalene dimethanol, 2,6-naphthalene dimethanol, 1,8-naphthalene dimethanol, 2,2′-biphenyl dimethanol, 4,4′-biphenyl dimethanol, phenyl glycol, glycidol, 2,3-butylene oxide, furfuryl alcohol, tetrahydrofurfuryl alcohol, 2-pyranol, 2-thiophene ethanol, Nicotinic alcohol, 2-piperidinol, 2,5-furan dimethanol, chloroethanol, dichloroethanol, trichloroethanol, 2-chloropropanol, 3-chloropropanol, 4-chlorobutanol, monofluoromethanol, trifluoromethanol, trifluoroethanol, pentafluoropropanol, heptafluorobutanol, p-chlorobenzyl alcohol, pentafluorobenzyl alcohol, p-nitrobenzyl alcohol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polybutylene glycol, polyvinyl alcohol, polyester polyols, phenoxyethanol, 3-phenoxypropanol, triethanolamine, triisopropanolamine, diethylaminopropanol, N-hydroxyethyl pyrrolidone, glycolic acid, methyl glycolate, lactic acid, methyl lactate, 3-hydroxypropionic acid or 4-hydroxybutyric acid.

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