Production method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen from dihydric alcohol through dehydrocyclization

Abstract

The invention discloses a production method of high-purity and ultra-high-purity lactone and high-content hydrogen prepared from dihydric alcohol through dehydrocyclization, which comprises the following steps: firstly activating dihydric alcohol and hydrogen raw materials, then carrying out catalytic synthesis and simple gas-liquid separation, and purifying the obtained mixed gas to obtain high-purity hydrogen. And the obtained liquid lactone product is pre-polymerized and then depolymerized to obtain the high-purity lactone. According to the method, high-purity lactone with the purity not lower than 95.0% and ultra-high-purity lactone with the purity not lower than 99.9% can be prepared, the problems existing in an existing production process are solved, high-content hydrogen with the content being 90-99% generated in the production process is collected, the additional economic benefits of the lactone preparation process are improved, and the method is suitable for industrial production. In addition, no extra organic solvent is introduced, no extra metal ions are brought and the like, so that the technological process is simple, easy to implement, green and environment-friendly, and safe application of the obtained lactone in the field of biomedical materials can be guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of production technology of fine chemicals, and specifically relates to a production method for preparing high-purity and ultra-high-purity lactones and high-content hydrogen by dehydrogenation and cyclization of diols. Background Art

[0002] Lactone is an oxygen-containing heterocyclic compound obtained by removing a molecule of water from a hydroxy acid molecule. It is not only an excellent solvent, extractant and absorbent with high boiling point and good solubility, but also an important organic intermediate that can be used in the synthesis of drug synthesis, biodegradable polymer materials, etc. At the same time, polyester materials obtained from lactone monomers through ring-opening polymerization have been widely used in the field of biomedical materials due to their excellent mechanical properties, biocompatibility and biodegradability. However, the field of biomedical materials requires that the prepared polyester materials have high purity, and one of the key factors is that the purity of the lactone monomer itself must be high.

[0003] Dehydrogenation and cyclization of diols is a common method for industrial preparation of lactones. This method directly uses diols to obtain lactones through one-step catalytic dehydrogenation and internal cyclization under the action of metal or non-metal compounds. Patent CN 101920206 publicly reports a method for preparing γ-butyrolactone by dehydrogenation of 1,4-butanediol. Lactone with good purity can only be obtained after 20 hours of reaction. There is a problem of long reaction time, which is related to the high reaction energy barrier of one-step catalysis. Patent CN 112473675 publicly reports a catalyst and method for preparing lactone p-dioxanone PDO by dehydrogenation and cyclization of diethylene glycol. Since diols are prone to side reactions at high temperatures to form by-products such as cyclic ethers, the purity of the prepared lactone is only 80.58%. Although the purity can be further improved after a series of operations such as ethanol washing, oven drying, and distillation tower distillation, there are problems such as complicated and cumbersome purification process and ethanol is prone to fire accidents during the drying process. Patent CN 103764638 publicly reports a method for preparing γ-butyrolactone by catalytic dehydrogenation of 1,4-butanediol. The purity of the prepared γ-butyrolactone is low, and the content of by-products can reach 13-40%. In view of the low purity of lactone obtained by dehydrogenation and cyclization of diols, CN 114377422 publicly reports a purification process combining distillation and melt crystallization to obtain polymer-grade ε-caprolactone, but this method has high requirements for equipment and temperature control accuracy, and there are problems of complex operation and cumbersome steps. CN 101824023 publicly reports a method for purifying medical PDO monomers. By using mixed solvent extraction of organic solvent and water, acetone precipitation, and distillation in the presence of strong active hydrogen removal reagents (calcium hydride, lithium aluminum hydride, etc.), PDO with a yield of more than 75% and a purity of 99.5% is obtained, but it faces the problems of sewage, waste organic solvent treatment, and strong active hydrogen removal reagents such as calcium hydride being flammable and explosive when wet.

[0004] In addition, more importantly, while the diol is dehydrogenated and cyclized to obtain the lactone monomer, hydrogen, a high value-added product that can be used as green and environmentally friendly energy, is also produced. For example, CN 112279824 publicly reported that 1,4-butanediol dehydrogenation to produce γ-butyrolactone will produce a large amount of byproduct hydrogen, but the method for the hydrogen produced is only used for recycling in the entire system, so that the utilization rate and utilization value of hydrogen are low. In this regard, CN 106866587 publicly reported the separation and recovery process of 1,4-butanediol dehydrogenation to produce γ-butyrolactone hydrogen-rich tail gas, that is, through a series of cumbersome processes such as cooling, compression, cooling, temperature swing adsorption, vacuum distillation, etc., the recovery and utilization of hydrogen in the tail gas is realized, but due to the use of 1,4-butanediol dehydrogenation to produce γ-butyrolactone The process has more side reactions, which leads to a higher content of organic impurities in the tail gas and a lower purity of hydrogen, which leads to a complex hydrogen recovery process. In addition, the currently widely known hydrogen production methods also have similar situations of low hydrogen purity and more by-products. For example, in the methanol hydrogen production process, the hydrogen content before purification is usually only 74-75%, while the carbon dioxide content is as high as 23-24%; in the natural gas hydrogen production process, in addition to carbon dioxide impurities, it also contains impurities such as carbon monoxide, methane, and water vapor, so that the hydrogen content before purification is usually not higher than 75%. In the later stage, in order to obtain high-purity hydrogen, it is bound to cost a high purification cost. Summary of the invention

[0005] The purpose of the present invention is to provide a production method for preparing high-purity and ultra-high-purity lactones and high-content hydrogen by dehydrogenation and cyclization of diols in view of the problems existing in the prior art. The production method adopts the principle of first activating the diols to reduce the reaction energy barrier and then obtaining high-purity lactones and high-content hydrogen by catalytic dehydrogenation and cyclization, and obtains ultra-high-purity lactones by using the strategy of pre-condensation and then depolymerization of high-purity lactones.

[0006] The present invention provides a production method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols, and the production method comprises the following steps:

[0007] (1) The raw material diol and hydrogen are respectively pumped through a metering pump at a liquid hourly space velocity of 0.001-50h -1 Gas hourly space velocity 0.1-1000h -1 Enter the activation reaction pipeline, and stay for activation reaction with the activator fixed in the activation reaction pipeline at 120-280°C for 5-90 minutes;

[0008] (2) The activated diol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, wherein the temperatures of each stage are 180-280° C., 210-300° C., and 230-320° C., respectively, and react with the catalyst system A fixed in the reactor, and the residence reaction times are 1-30 min, 1-30 min, and 5-45 min, respectively, to obtain a mixed product containing lactone;

[0009] (3) The lactone-containing mixed product is cooled to 30-120° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and the high-content hydrogen enters a pre-machine buffer tank from the gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 5-30% of the high-content hydrogen returns to the reaction system buffer tank through a circulation pipeline, and 70-95% of the high-content hydrogen is obtained through a hydrogen purification and filling system to obtain high-purity hydrogen with a purity of 99.9999%;

[0010] (4) The liquid coming out of the gas-liquid separator is diverted through a diverter valve, 0-100% of the liquid enters a liquid storage tank to obtain high-purity lactone, and 0-100% of the liquid enters a prepolymerization reactor at a temperature of 20-140° C. through a delivery pipeline, and undergoes a polymerization reaction for 10-90 minutes under the action of the catalyst system B to generate polylactone oligomers;

[0011] (5) The obtained polylactone oligomer flows through a vacuum pipeline at a temperature of 60-140° C. and a pressure of 4000-8000 Pa, and then enters a depolymerization reactor, where it reacts under the action of the catalyst system C at a temperature of 100-200° C. and a vacuum degree of 10-3000 Pa. The collected gas phase product enters a collection chamber after condensation to obtain ultra-high purity lactone.

[0012] The liquid separated by the diverter valve in the above production method can flow only into the lactone product liquid storage tank, can also flow only into the prepolymerization reactor, or can flow into both the lactone product liquid storage tank and the prepolymerization reactor at the same time.

[0013] The liquid hourly space velocity of the diol in the above production method is preferably 25-50h -1 When the lactone purity in the lactone product storage tank in step (4) is 80.30-95.00%, the purity of the lactone product obtained in step (5) is 98.80-99.92%; the liquid hourly space velocity of the diol is preferably 10-25h -1 When the lactone purity in the lactone product storage tank in step (4) is 85.00-96.50%, the purity of the lactone product obtained in step (5) is 99.90-99.95%; the liquid hourly space velocity of the diol is preferably 2-10h -1When the lactone purity in the lactone product storage tank in step (4) is 91.40-98.00%, the purity of the lactone product obtained in step (5) is 99.90-99.99%; the liquid hourly space velocity of the diol is preferably 0.5-2h -1 When the lactone purity in the lactone product storage tank in step (4) is 95.00-99.00%, the purity of the lactone product obtained in step (5) is 99.92-99.999%; the liquid hourly space velocity of the diol is preferably 0.001-0.5h -1 When the lactone product in the lactone product storage tank in step (4) has a purity of 99.00-99.90%, the purity of the lactone product obtained in step (5) is 99.95-99.999%.

[0014] The diol described in the above production method is any one of 1,4-butanediol, diethylene glycol, 1,5-pentanediol or 1,6-hexanediol.

[0015] The activator described in the above production method is a copper hydroxyphosphate metal salt supported on a carbon fiber carrier, and the copper hydroxyphosphate metal salt is of the general formula M a x A compound of Cu[(OH)PO4], wherein M is a doping metal selected from at least one metal of Group IIA, Group IIIA, Group IIB, Group VB, Group VIB and Group VIB in the periodic table, and a and x can be any positive numbers but must satisfy ax=2.

[0016] The activator described in the above production method is prepared by such a method: firstly immerse the carbon fiber in a copper chloride or copper nitrate aqueous solution, then add an aqueous solution of a doped metal salt thereto, and then add a mixed aqueous solution of monohydrogen phosphate or dihydrogen phosphate and hydroxycarboxylate for precipitation, filter and wash after precipitation, and dry at 80-120°C for 8-16h, and finally calcine at 180-250°C and 300-600°C for 1-3h respectively. The molar ratio of the copper chloride or copper nitrate, the doped metal salt, the monohydrogen phosphate or the dihydrogen phosphate used is 1:(0.33-0.5):1, the hydroxycarboxylate used is 0.5-5% of the mass of the monohydrogen phosphate or the dihydrogen phosphate; the doped metal salt used is a chloride or nitrate compound of at least one of Group IIA, Group IIIA, Group IIB, Group VB, Group VIB and Group VIB in the periodic table; the monohydrogen phosphate used is any one of sodium monohydrogen phosphate, potassium monohydrogen phosphate and ammonium monohydrogen phosphate; the dihydrogen phosphate used is any one of sodium dihydrogen phosphate, potassium dihydrogen phosphate and ammonium dihydrogen phosphate; the hydroxycarboxylate used is any one of the sodium salt, potassium salt or ammonium salt of 6-hydroxycaproic acid, 5-hydroxyvaleric acid, (2-hydroxyethoxy)acetic acid, 4-hydroxybutyric acid and 2-hydroxyisobutyric acid.

[0017] The catalytic system A described in the above production method is a copper-zinc-cerium catalyst or a copper-zinc-lanthanum catalyst composed of a copper compound, a zinc compound and a catalytic promoter disclosed in the prior art CN 1325162 and an activator, and the mass ratio of the activator to the catalyst in each fixed catalytic system A in the three-stage catalytic synthesis reactor is 0.01-2%, 0.5-10% and 1-15% respectively.

[0018] The lactone obtained in the above production method is any one of γ-butyrolactone, p-dioxanone, δ-valerolactone or ε-caprolactone.

[0019] The high-content hydrogen obtained in the above production method is a high-content hydrogen with a content of 90-99%.

[0020] The hydrogen purification and filling system described in the above production method is a commonly used system in industrial hydrogen production, usually consisting of a gas separation device, a primary compression device, a TSA purification device, a PSA purification device, a secondary compression device and a hydrogen filling device.

[0021] The polylactone oligomer described in the above production method is any one of a poly(γ-butyrolactone) oligomer, a polydioxanone oligomer, a poly(δ-valerolactone) oligomer or a poly(ε-caprolactone) oligomer.

[0022] The catalytic system B described in the above production method is a catalyst used for the lactone ring-opening polymerization reaction, which is usually any one of stannous octoate, tert-butyl potassium, triethylaluminum, alkoxyaluminum, Salen aluminum complex, N-heterocyclic carbene, diazabicycle, hexacyclic bicyclic guanidine, 7-methyl hexacyclic bicyclic guanidine, phthalimide, 4-dimethylaminopyridine, diphenyl phosphate, phosphazene base, thiazolium salt or (thio)urea / base two-component catalyst.

[0023] The catalytic system C described in the above production method is at least one of the molecular sieve solid catalytic system, acidic solid catalytic system and alkaline solid catalytic system disclosed in the prior art CN 103880813, preferably at least one of a ZSM-5 molecular sieve solid catalyst, an MCM-41 molecular sieve solid catalyst, an EPZ-10 molecular sieve solid catalyst, a silica acidic solid catalyst, an aluminum oxide acidic solid catalyst, a boron trioxide acidic solid catalyst, a zinc oxide alkaline solid catalyst, a magnesium oxide alkaline solid catalyst and a lanthanum oxide alkaline solid catalyst.

[0024] The liquid storage tank and the collecting chamber in the above production method are made of Hastelloy, titanium alloy, polytetrafluoroethylene, glass, enamel, stainless steel, stainless steel lined with polytetrafluoroethylene or copper alloy lined with polytetrafluoroethylene.

[0025] The material used for the connecting pipe between the depolymerization reactor and the collection chamber in the above production method is Hastelloy, titanium alloy, polytetrafluoroethylene, glass, enamel, stainless steel, stainless steel lined with polytetrafluoroethylene or copper alloy lined with polytetrafluoroethylene.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] 1. Since the production method provided by the present invention adopts the technical process of activating the diol raw material first and then catalytically synthesizing it, and prepolymerizing the lactone first and then depolymerizing it, a high-purity lactone with a purity of not less than 95.0% and an ultra-high-purity lactone with a purity of not less than 99.9% can be prepared, which solves the problems of low purity of the prepared lactone in the existing production process and the need for subsequent complex and cumbersome continuous refining and separation operations or seriously polluting organic separation and purification to achieve the preparation of high-purity monomers.

[0028] 2. Since the production method provided by the present invention obtains high-value lactone and high-content hydrogen with a content of 90-99%, and the obtained hydrogen content is much higher than the hydrogen content obtained by traditional hydrogen production methods such as methanol hydrogen production and natural gas hydrogen production, the preparation of high-purity hydrogen from this high-content hydrogen can reduce the purification cost, which not only realizes the high-value utilization of hydrogen, but also improves the additional economic benefits of the lactone preparation process.

[0029] 3. Since the production method provided by the present invention does not introduce any additional organic solvents other than raw materials and catalysts, the process is simple, easy to implement, and environmentally friendly.

[0030] 4. Since the collection chamber used in the production method provided by the present invention and the connecting pipe between the depolymerization reactor and the collection chamber are made of special materials with outstanding corrosion resistance or metal materials with anti-corrosion coating, the problem of additional metal ions introduced due to corrosion of the collection chamber and the pipeline is avoided, and the purity of the lactone is further improved, thereby ensuring its safe application in the field of biomedical materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the H NMR spectrum analysis of the lactone prepared in Example 9 of the present invention. In the figure, a, b, and c respectively represent the positions of the groups shown in the structural formula, which proves that the lactone has been successfully synthesized.

[0032] Figure 2 This is the gas chromatography analysis spectrum of the lactone prepared in Example 9 of the present invention. It can be seen from the figure that the absorption peak corresponding to the retention time of 5.06 min is the sample peak of the ultra-high purity lactone prepared in Example 9 of the present invention, and the purity of the sample can reach 99.9929%.

[0033] Figure 3This is the gas chromatography analysis spectrum of the lactone prepared in Example 11 of the present invention. It can be seen from the figure that the absorption peak corresponding to the retention time of 5.14 min is the sample peak of the ultra-high purity lactone prepared in Example 10 of the present invention, and the purity of the sample can reach 99.9876%.

[0034] Figure 4 This is the gas chromatography analysis spectrum of the lactone prepared in Example 11 of the present invention. It can be seen from the figure that the absorption peak corresponding to the retention time of 5.193 min is the sample peak of the ultra-high purity lactone prepared in Example 11 of the present invention, and the purity (concentration) of the sample can reach 99.9420%.

[0035] Figure 5 This is the gas chromatography analysis spectrum of the lactone prepared in Example 17 of the present invention. From the figure, it can be seen that the absorption peak corresponding to the retention time of 12.699 min is the sample peak of the ultra-high purity lactone prepared in Example 17 of the present invention, and the purity (concentration) of the sample can reach 99.9742%.

[0036] Figure 6 This is the gas chromatography analysis spectrum of the lactone prepared in Example 19 of the present invention. From the figure, it can be seen that the absorption peak corresponding to the retention time of 13.118 min is the sample peak of the ultra-high purity lactone prepared in Example 19 of the present invention, and the purity (concentration) of the sample can reach 99.9932%. DETAILED DESCRIPTION

[0037] The following examples are given to further illustrate the present invention. It is necessary to point out that the following are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the following examples. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It is particularly emphasized that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

[0038] It is worth noting that the purity of lactones prepared in the following examples is obtained by directly testing the lactones in the liquid storage tank and the collection chamber using a GC9160 gas chromatograph (Shanghai Ouhua Analytical Instrument Factory). Examples 1-5 are the preparation of hydroxy copper phosphate metal salt activators supported on carbon fiber carriers, and Examples 6-20 are examples of simultaneously preparing high-purity and ultra-high-purity lactones and high-content hydrogen by dehydrogenation and cyclization of diols.

[0039] Example 1

[0040] First, soak the carbon fiber in 50g of copper chloride aqueous solution, then add an aqueous solution of 15.8g of chromium chloride and 20.0g of aluminum chloride, and then add a mixed aqueous solution of 70.98g of sodium monohydrogen phosphate and 0.35g of sodium 4-hydroxybutyrate for precipitation. After precipitation, filter, wash, and dry at 80°C for 16h, and finally calcine at 180°C and 400°C for 3h and 1h, respectively, to obtain a hydroxy copper phosphate-chromium-aluminum activator loaded on a carbon fiber carrier.

[0041] Example 2

[0042] First, soak the carbon fiber in 93.8g of copper nitrate aqueous solution, then add 15.8g of chromium chloride and 10.5g of ferric chloride aqueous solution, and then add 87.1g of potassium monohydrogen phosphate and 4.36g of (2-hydroxyethoxy) potassium acetate mixed aqueous solution for precipitation. After precipitation, filter, wash, and dry at 120°C for 8h, and finally calcine at 250°C and 500°C for 3h and 1h, respectively, to obtain a hydroxy copper phosphate-chromium-iron activator loaded on a carbon fiber carrier.

[0043] Example 3

[0044] First, the carbon fiber is soaked in 93.8g of copper nitrate aqueous solution, and then an aqueous solution of 15.8g of chromium chloride, 16.2g of ferric chloride and 10.6g of aluminum nitrate is added thereto, and then a mixed aqueous solution of 68.0g of potassium dihydrogen phosphate and 2.72g of (2-hydroxyethoxy) ammonium acetate is added for precipitation. After the precipitation is completed, it is filtered, washed, and dried at 120°C for 8h, and finally calcined at 250°C and 600°C for 3h and 1h, respectively, to obtain a hydroxy copper phosphate-chromium-aluminum-iron activator loaded on a carbon fiber carrier.

[0045] Example 4

[0046] First, the carbon fiber is soaked in 93.8g of copper nitrate aqueous solution, and then an aqueous solution of 14.5g of vanadium nitrate, 6.7g of aluminum chloride and 12.1g of ferric nitrate is added thereto, and then a mixed aqueous solution of 57.5g of ammonium dihydrogen phosphate and 1.72g of 2-hydroxyammonium isobutyrate is added for precipitation. After the precipitation is completed, it is filtered, washed, and dried at 120°C for 8h, and finally calcined at 230°C and 500°C for 2h and 1.5h, respectively, to obtain a hydroxy copper phosphate-vanadium-aluminum-iron activator loaded on a carbon fiber carrier.

[0047] Example 5

[0048] First, the carbon fiber is soaked in 50g of copper chloride aqueous solution, and then an aqueous solution of 7.9g of chromium chloride, 9.5g of zinc nitrate and 15.6g of barium chloride is added thereto, and then a mixed aqueous solution of 60.0g of sodium dihydrogen phosphate and 1.2g of sodium 6-hydroxyhexanoate is added for precipitation. After the precipitation is completed, it is filtered, washed, and dried at 100°C for 12h, and finally calcined at 200°C and 450°C for 3h and 1h, respectively, to obtain a hydroxy copper phosphate-chromium-zinc-barium activator loaded on a carbon fiber carrier.

[0049] Example 6

[0050] (1) 1,4-Butanediol and hydrogen were respectively discharged at a liquid hourly space velocity of 0.2 h -1 Heqi hourly speed 18h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with the hydroxy copper-chromium-aluminum phosphate fixed in the activation reaction pipeline at 120°C, with a residence time of 20 minutes;

[0051] (2) The activated 1,4-butanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 200° C., 240° C., and 280° C., respectively, and react with a copper-zinc-cerium catalyst and 0.1% copper-chromium-aluminum hydroxyphosphate, a copper-zinc-cerium catalyst and 1% copper-chromium-aluminum hydroxyphosphate, and a copper-zinc-cerium catalyst and 5% copper-chromium-aluminum hydroxyphosphate fixed in each stage of the reactor, with residence times of 10 min, 15 min, and 20 min, respectively, to obtain a mixed product containing γ-butyrolactone;

[0052] (3) The mixed product containing γ-butyrolactone is cooled to 30°C by a heat exchange system, condensed and then enters a gas-liquid separator. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 98% enters a pre-machine buffer tank from the gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 5% of the high-content hydrogen gas with a content of 98% returns to the buffer tank of the reaction system through a circulation pipeline, and 95% of the high-content hydrogen gas with a content of 98% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0053] (4) the liquid coming out of the gas-liquid separator is split by a diverter valve, 90% of the liquid enters a liquid storage tank to obtain γ-butyrolactone with a purity of 99.81%, and 10% of the liquid enters a prepolymerization reactor at a temperature of 20° C. through a delivery pipeline, and reacts for 20 minutes under the action of a 7-methyl hexacyclic bicyclic guanidine catalyst to generate poly(γ-butyrolactone) oligomers;

[0054] (5) The obtained poly (γ-butyrolactone) oligomer flows through a vacuum pipe at a temperature of 60°C and a pressure of 4000Pa, and then enters a depolymerization reactor, where it reacts under the action of an acidic solid catalyst of aluminum oxide at a temperature of 100°C and a vacuum degree of 150Pa. The collected gas phase product enters a collection chamber after condensation, and γ-butyrolactone with a purity of 99.995% is obtained.

[0055] Example 7

[0056] (1) 1,4-Butanediol and hydrogen were respectively discharged at a liquid hourly space velocity (LHSV) of 1 h -1 Heqi space speed 25h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with the hydroxy copper-chromium-aluminum phosphate fixed in the activation reaction pipeline at 180°C, with a residence time of 30 minutes;

[0057] (2) The activated 1,4-butanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each section of which has a temperature of 220° C., 240° C., and 290° C., respectively, and react with a copper-zinc-lanthanum catalyst and 1% copper-chromium-aluminum hydroxyphosphate, a copper-zinc-lanthanum catalyst and 5% copper-chromium-aluminum hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 12% copper-chromium-aluminum hydroxyphosphate fixed in each section of the reactor, with residence times of 10 min, 12 min, and 18 min, respectively, to obtain a mixed product containing γ-butyrolactone;

[0058] (3) The mixed product containing γ-butyrolactone is cooled to 35° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 97.5% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 10% of the high-content hydrogen gas with a content of 97.5% returns to the buffer tank of the reaction system through a circulation pipeline, and 90% of the high-content hydrogen gas with a content of 97.5% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0059] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 10% of the liquid enters a liquid storage tank to obtain γ-butyrolactone with a purity of 98.57%, and 90% of the liquid enters a prepolymerization reactor at a temperature of 20° C. through a delivery pipeline, and reacts for 15 minutes under the action of a diazabicyclic catalyst to generate poly(γ-butyrolactone) oligomers;

[0060] (5) The obtained poly (γ-butyrolactone) oligomer flows through a vacuum pipe at a temperature of 80° C. and a pressure of 5000 Pa, and then enters a depolymerization reactor, where it reacts under the action of a zinc oxide alkaline solid catalyst at a temperature of 130° C. and a vacuum degree of 180 Pa. The collected gas phase product enters a collection chamber after condensation, and γ-butyrolactone with a purity of 99.99% is obtained.

[0061] Example 8

[0062] (1) 1,4-Butanediol and hydrogen were respectively discharged at a liquid hourly space velocity of 3 h -1 Heqi hourly space velocity 50h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with the hydroxy copper-chromium-aluminum phosphate fixed in the activation reaction pipeline at 220°C, with a residence time of 35 minutes;

[0063] (2) The activated 1,4-butanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each section of which has a temperature of 240° C., 260° C., and 300° C., respectively, and react with a copper-zinc-lanthanum catalyst and 2% copper-chromium-aluminum hydroxyphosphate, a copper-zinc-lanthanum catalyst and 5% copper-chromium-aluminum hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 15% copper-chromium-aluminum hydroxyphosphate fixed in each section of the reactor, with residence times of 8 min, 11 min, and 19 min, respectively, to obtain a mixed product containing γ-butyrolactone;

[0064] (3) The mixed product containing γ-butyrolactone is cooled to 45°C by a heat exchange system, condensed and then enters a gas-liquid separator, the separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 97% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 12% of the high-content hydrogen gas with a content of 97% returns to the buffer tank of the reaction system through a circulation pipeline, and 88% of the high-content hydrogen gas with a content of 97% is passed through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0065] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 40% of the liquid enters a liquid storage tank to obtain γ-butyrolactone with a purity of 97.16%, and 60% of the liquid product enters a prepolymerization reactor at a temperature of 25° C. through a delivery pipeline, and reacts for 14 minutes under the action of a thiazolium salt catalyst to generate poly(γ-butyrolactone) oligomers;

[0066] (5) The obtained poly (γ-butyrolactone) oligomer flows through a vacuum pipeline at a temperature of 80° C. and a pressure of 5000 Pa, and then enters a depolymerization reactor, where it reacts under the combined action of ZSM-5, EPZ-10 and MCM-41 molecular sieve solid catalysts at a temperature of 120° C. and a vacuum degree of 150 Pa. The collected gas phase product enters a collection chamber after condensation, and γ-butyrolactone with a purity of 99.91% is obtained.

[0067] Example 9

[0068] (1) Diethylene glycol and hydrogen were respectively discharged at a liquid hourly space velocity of 0.01 h -1 Heqi air speed 8h -1It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-iron fixed in the activation reaction pipeline at 120°C, with a residence time of 15 minutes;

[0069] (2) The activated diethylene glycol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 180° C., 210° C., and 260° C., respectively, and react with a copper-zinc-lanthanum catalyst and 0.1% copper-chromium-iron hydroxyphosphate, a copper-zinc-lanthanum catalyst and 0.5% copper-chromium-iron hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 1% copper-chromium-iron hydroxyphosphate fixed in each stage of the reactor, with residence times of 20 min, 20 min, and 20 min, respectively, to obtain a mixed product containing p-dioxanone;

[0070] (3 The mixed product containing p-dioxanone is cooled to 120°C by the heat exchange system, and enters the gas-liquid separator after condensation. The separated liquid enters the liquid storage tank, and the high-content hydrogen with a content of 99% enters the pre-machine buffer tank from the gas outlet of the gas-liquid separator, and then enters the hydrogen compressor, of which 5% of the high-content hydrogen with a content of 99% returns to the reaction system buffer tank through the circulation pipeline, and 95% of the high-content hydrogen with a content of 99% is obtained by the hydrogen purification and filling system to obtain high-purity hydrogen with a purity of 99.9999%;

[0071] (4) The liquid coming out of the gas-liquid separator is diverted through a diverter valve, 2% of the liquid product enters a liquid storage tank to obtain p-dioxanone with a purity of 99.90%, and 98% of the liquid product enters a prepolymerization reactor at a temperature of 120° C. through a delivery pipeline, and reacts for 60 minutes under the action of a thiazolium salt catalyst to generate poly-p-dioxanone oligomers;

[0072] (5) The obtained polydioxanone oligomer flows through a vacuum pipe at a temperature of 80° C. and a pressure of 4000 Pa, and then enters a depolymerization reactor, where it reacts under the action of a ZSM-5 molecular sieve type solid catalyst at a temperature of 160° C. and a vacuum degree of 500 Pa. The collected gas phase product enters a collection chamber after condensation, and polydioxanone with a purity of 99.993% is obtained.

[0073] Example 10

[0074] (1) Diethylene glycol and hydrogen were respectively discharged at a liquid hourly space velocity of 1 h -1 Heqi hourly space velocity 10h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-iron fixed in the activation reaction pipeline at 140°C, with a residence time of 20 minutes;

[0075] (2) The activated diethylene glycol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 190° C., 230° C., and 260° C., respectively, and react with a copper-zinc-lanthanum catalyst and 0.4% copper-chromium-iron hydroxyphosphate, a copper-zinc-lanthanum catalyst and 0.7% copper-chromium-iron hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 1.5% copper-chromium-iron hydroxyphosphate fixed in each stage of the reactor, with residence times of 20 min, 20 min, and 30 min, respectively, to obtain a mixed product containing p-dioxanone;

[0076] (3) The mixed product containing p-dioxanone is cooled to 100° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 91.4% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 10% of the high-content hydrogen gas with a content of 91.4% returns to the buffer tank of the reaction system through a circulation pipeline, and 90% of the high-content hydrogen gas with a content of 91.4% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0077] (4) The liquid coming out of the gas-liquid separator is split through a diverter valve, 75% of the liquid enters a liquid storage tank to obtain p-dioxanone with a purity of 98.87%, and 25% of the liquid enters a prepolymerization reactor at a temperature of 120° C. through a delivery pipeline, and reacts for 40 minutes under the action of stannous octoate catalyst to generate poly-p-dioxanone oligomers;

[0078] (5) The obtained polydioxanone oligomer flows through a vacuum pipeline at a temperature of 90° C. and a pressure of 4200 Pa, and then enters a depolymerization reactor, where it reacts under the action of a ZSM-5 molecular sieve type solid catalyst at a temperature of 170° C. and a vacuum degree of 500 Pa. The collected gas phase product enters a collection chamber after condensation, and polydioxanone with a purity of 99.990% is obtained.

[0079] Embodiment 11

[0080] (1) Diethylene glycol and hydrogen were respectively heated at a liquid hourly space velocity of 7 h -1 Heqi hourly speed 45h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-iron fixed in the activation reaction pipeline at 180°C, with a residence time of 40 minutes;

[0081] (2) The activated diethylene glycol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 220° C., 250° C., and 290° C., respectively, and react with a copper-zinc-cerium catalyst and 0.9% copper-chromium-iron hydroxyphosphate, a copper-zinc-cerium catalyst and 3% copper-chromium-iron hydroxyphosphate, and a copper-zinc-cerium catalyst and 8% copper-chromium-iron hydroxyphosphate fixed in each stage of the reactor, with residence times of 25 min, 20 min, and 35 min, respectively, to obtain a mixed product containing p-dioxanone;

[0082] (3) The mixed product containing p-dioxanone is cooled to 75° C. by a heat exchange system, condensed and then enters a gas-liquid separator, the separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 90% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 15% of the high-content hydrogen gas with a content of 90% returns to the buffer tank of the reaction system through a circulation pipeline, and 85% of the high-content hydrogen gas with a content of 90% is passed through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0083] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 99% of the liquid enters a liquid storage tank to obtain 4-dioxanone with a purity of 97.995%, and 1% of the liquid enters a prepolymerization reactor at a temperature of 130° C. through a delivery pipeline, and reacts for 30 minutes under the action of stannous octoate catalyst to generate poly-4-dioxanone oligomers;

[0084] (5) The obtained polydioxanone oligomer flows through a vacuum pipe at a temperature of 100° C. and a pressure of 4000 Pa, and then enters a depolymerization reactor, where it reacts under the action of a zinc oxide alkaline solid catalyst at a temperature of 160° C. and a vacuum degree of 300 Pa. The collected gas phase product enters a collection chamber after condensation, and polydioxanone with a purity of 99.9876% is obtained.

[0085] Example 12

[0086] (1) Diethylene glycol and hydrogen were respectively discharged at a liquid hourly space velocity of 13 h -1 Heqi space speed 99h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-iron fixed in the activation reaction pipeline at 280°C, with a residence time of 20 minutes;

[0087] (2) The activated diethylene glycol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 280° C., 300° C., and 320° C., respectively, and react with a copper-zinc-cerium catalyst and 0.9% copper-chromium-iron hydroxyphosphate, a copper-zinc-cerium catalyst and 3% copper-chromium-iron hydroxyphosphate, and a copper-zinc-cerium catalyst and 8% copper-chromium-iron hydroxyphosphate fixed in each stage of the reactor, with residence times of 7 min, 5 min, and 3 min, respectively, to obtain a mixed product containing p-dioxanone;

[0088] (3) The mixed product containing p-dioxanone is cooled to 70° C. by a heat exchange system, condensed and then enters a gas-liquid separator, the separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 92.5% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 20% of the high-content hydrogen gas with a content of 92.5% returns to the buffer tank of the reaction system through a circulation pipeline, and 80% of the high-content hydrogen gas with a content of 92.5% is passed through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0089] (4) The liquid coming out of the gas-liquid separator is split through a diverter valve, 35% of the liquid enters a liquid storage tank to obtain p-dioxanone with a purity of 96.193%, and 65% of the liquid enters a prepolymerization reactor at a temperature of 120° C. through a delivery pipeline, and reacts for 40 minutes under the action of stannous octoate catalyst to generate poly-p-dioxanone oligomers;

[0090] (5) The obtained polydioxanone oligomer flows through a vacuum pipe at a temperature of 100° C. and a pressure of 4000 Pa, and then enters a depolymerization reactor, where it reacts under the action of a zinc oxide alkaline solid catalyst at a temperature of 140° C. and a vacuum degree of 200 Pa. The collected gas phase product enters a collection chamber after condensation, and polydioxanone with a purity of 99.942% is obtained.

[0091] Example 13

[0092] (1) Diethylene glycol and hydrogen were respectively heated at a liquid hourly space velocity of 25.5 h -1 Heqi hourly space velocity 130h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-iron fixed in the activation reaction pipeline at 230°C, with a residence time of 25 minutes;

[0093] (2) The activated diethylene glycol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 240° C., 270° C., and 300° C., respectively, and react with a copper-zinc-cerium catalyst and 2% copper-chromium-iron hydroxyphosphate, a copper-zinc-lanthanum catalyst and 10% copper-chromium-iron hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 12% copper-chromium-iron hydroxyphosphate fixed in each stage of the reactor, with residence times of 20 min, 20 min, and 25 min, respectively, to obtain a mixed product containing p-dioxanone;

[0094] (3) The mixed product containing p-dioxanone is cooled to 60° C. by a heat exchange system, condensed and then enters a gas-liquid separator, the separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 93% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 30% of the high-content hydrogen gas with a content of 93% returns to the buffer tank of the reaction system through a circulation pipeline, and 70% of the high-content hydrogen gas with a content of 93% is passed through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0095] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 80% of the liquid enters a liquid storage tank to obtain 95% pure dioxanone, and 20% of the liquid enters a prepolymerization reactor at a temperature of 110° C. through a delivery pipeline, and reacts for 30 minutes under the action of stannous octoate catalyst to generate polydioxanone oligomers;

[0096] (5) The obtained polydioxanone oligomer flows through a vacuum pipe at a temperature of 85° C. and a pressure of 4000 Pa, and then enters a depolymerization reactor, where it reacts under the combined action of aluminum oxide and boron trioxide acidic solid catalysts at a temperature of 130° C. and a vacuum degree of 150 Pa. The collected gas phase product enters a collection chamber after condensation, and polydioxanone with a purity of 99.92% is obtained.

[0097] Embodiment 14

[0098] (1) Diethylene glycol and hydrogen were respectively discharged at a liquid hourly space velocity of 1.9 h -1 Heqi hourly space velocity 50h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with the hydroxy copper phosphate-vanadium-aluminum-iron fixed in the activation reaction pipeline at 220°C, with a residence time of 30 minutes;

[0099] (2) The activated diethylene glycol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 240° C., 270° C., and 300° C., respectively, and react with a copper-zinc-cerium catalyst and 1.5% copper-hydroxyphosphate-vanadium-aluminum-iron, a copper-zinc-lanthanum catalyst and 9% copper-hydroxyphosphate-vanadium-aluminum-iron, and a copper-zinc-lanthanum catalyst and 12% copper-hydroxyphosphate-vanadium-aluminum-iron fixed in each stage of the reactor, with residence times of 20 min, 20 min, and 25 min, respectively, to obtain a mixed product containing p-dioxanone;

[0100] (3) The mixed product containing p-dioxanone is cooled to 70° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 96% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 13% of the high-content hydrogen gas with a content of 96% returns to the buffer tank of the reaction system through a circulation pipeline, and 87% of the high-content hydrogen gas with a content of 96% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0101] (4) The liquid coming out of the gas-liquid separator is split through a diverter valve, 35% of the liquid enters a liquid storage tank to obtain 99% pure p-dioxanone, and 65% of the liquid enters a prepolymerization reactor at a temperature of 130° C. through a delivery pipeline, and reacts for 30 minutes under the action of stannous octoate catalyst to generate poly(p-dioxanone) oligomers;

[0102] (5) The obtained polydioxanone oligomer flows through a vacuum pipe at a temperature of 85° C. and a pressure of 4000 Pa, and then enters a depolymerization reactor, where it reacts under the action of an acidic solid aluminum oxide catalyst at a temperature of 120° C. and a vacuum degree of 150 Pa. The collected gas phase product enters a collection chamber after condensation, and polydioxanone with a purity of 99.997% is obtained.

[0103] Embodiment 15

[0104] (1) Diethylene glycol and hydrogen were respectively discharged at a liquid hourly space velocity of 0.4 h -1 Heqi hourly space velocity 15h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with the hydroxy copper-chromium-zinc-barium phosphate fixed in the activation reaction pipeline at 210°C, with a residence time of 10 minutes;

[0105] (2) The activated diethylene glycol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 240° C., 260° C., and 300° C., respectively, and react with a copper-zinc-cerium catalyst and 1.5% copper-chromium-zinc-barium hydroxyphosphate, a copper-zinc-lanthanum catalyst and 2% copper-chromium-zinc-barium hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 2% copper-chromium-zinc-barium hydroxyphosphate fixed in each stage of the reactor, with residence times of 10 min, 15 min, and 20 min, respectively, to obtain a mixed product containing p-dioxanone;

[0106] (3) The mixed product containing p-dioxanone is cooled to 65° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 99% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 6% of the high-content hydrogen gas with a content of 99% returns to the buffer tank of the reaction system through a circulation pipeline, and 94% of the high-content hydrogen gas with a content of 99% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0107] (4) The liquid coming out of the gas-liquid separator is split through a diverter valve, 3% of the liquid enters a liquid storage tank to obtain 4-dioxanone with a purity of 99.9%, and 97% of the liquid enters a prepolymerization reactor at a temperature of 110° C. through a delivery pipeline, and reacts for 15 minutes under the action of stannous octoate catalyst to generate poly-4-dioxanone oligomers;

[0108] (5) The obtained polydioxanone oligomer flows through a vacuum pipe at a temperature of 80° C. and a pressure of 4000 Pa, and then enters a depolymerization reactor, where it reacts under the action of an acidic solid aluminum oxide catalyst at a temperature of 130° C. and a vacuum degree of 200 Pa. The collected gas phase product enters a collection chamber after condensation, and polydioxanone with a purity of 99.9991% is obtained.

[0109] Example 16

[0110] (1) 1,5-pentanediol and hydrogen were respectively discharged at a liquid hourly space velocity of 0.8 h -1 Heqi hourly speed 90h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-aluminum-iron fixed in the activation reaction pipeline at 140°C, with a residence time of 30 minutes;

[0111] (2) The activated 1,5-pentanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each section of which has a temperature of 180° C., 210° C., and 240° C., respectively, and react with a copper-zinc-cerium catalyst and 0.5% copper-chromium-aluminum-iron hydroxyphosphate, a copper-zinc-cerium catalyst and 0.5% copper-chromium-aluminum-iron hydroxyphosphate, and a copper-zinc-cerium catalyst and 0.5% copper-chromium-aluminum-iron hydroxyphosphate fixed in each section of the reactor, with residence times of 15 min, 15 min, and 10 min, respectively, to obtain a mixed product containing δ-valerolactone;

[0112] (3) The mixed product containing δ-valerolactone is cooled to 70° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 98% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 9% of the high-content hydrogen gas with a content of 98% returns to the buffer tank of the reaction system through a circulation pipeline, and 91% of the high-content hydrogen gas with a content of 98% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0113] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 90% of the liquid enters a liquid storage tank to obtain δ-valerolactone with a purity of 98.55%, and 10% of the liquid enters a prepolymerization reactor at a temperature of 130° C. through a delivery pipeline, and reacts for 20 minutes under the action of a thiazolium salt catalyst to generate poly(δ-valerolactone) oligomers;

[0114] (5) The obtained poly (δ-valerolactone) oligomer flows through a vacuum pipe at a temperature of 90°C and a pressure of 4000Pa, and then enters a depolymerization reactor, where it reacts under the action of an EPZ-10 molecular sieve type solid catalyst at a temperature of 150°C and a vacuum degree of 50Pa. The collected gas phase product enters a collection chamber after condensation, and δ-valerolactone with a purity of 99.933% is obtained.

[0115] Embodiment 17

[0116] (1) 1,5-pentanediol and hydrogen were respectively discharged at a liquid hourly space velocity of 0.4 h -1 Heqi hourly space velocity 20h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-aluminum-iron fixed in the activation reaction pipeline at 130°C, with a residence time of 40 minutes;

[0117] (2) The activated 1,5-pentanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each section of which has a temperature of 180° C., 210° C., and 240° C., respectively, and react with a copper-zinc-cerium catalyst and 0.01% copper-chromium-aluminum-iron hydroxyphosphate, a copper-zinc-cerium catalyst and 0.5% copper-chromium-aluminum-iron hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 0.5% copper-chromium-aluminum-iron hydroxyphosphate fixed in each section of the reactor, with residence times of 10 min, 15 min, and 10 min, respectively, to obtain a mixed product containing δ-valerolactone;

[0118] (3) The mixed product containing δ-valerolactone is cooled to 120° C. by a heat exchange system, condensed and then enters a gas-liquid separator, the separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 97.5% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 15% of the high-content hydrogen gas with a content of 97.5% returns to the buffer tank of the reaction system through a circulation pipeline, and 85% of the high-content hydrogen gas with a content of 97.5% is passed through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0119] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 50% of the liquid enters a liquid storage tank to obtain δ-valerolactone with a purity of 99.89%, and 50% of the liquid enters a prepolymerization reactor at a temperature of 120° C. through a delivery pipeline, and reacts for 18 minutes under the action of a six-membered bicyclic guanidine catalyst to generate poly(δ-valerolactone) oligomers;

[0120] (5) The obtained poly (δ-valerolactone) oligomer flows through a vacuum pipe at a temperature of 85°C and a pressure of 4000Pa, and then enters a depolymerization reactor, where it reacts under the action of a boron trioxide acidic solid catalyst at a temperature of 145°C and a vacuum degree of 50Pa. The collected gas phase product enters a collection chamber after condensation, and δ-valerolactone with a purity of 99.9742% is obtained.

[0121] Embodiment 18

[0122] (1) 1,5-pentanediol and hydrogen were respectively discharged at a liquid hourly space velocity (LHSV) of 1 h -1 Heqi hourly space velocity 35h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-aluminum-iron fixed in the activation reaction pipeline at 260°C, with a residence time of 10 minutes;

[0123] (2) The activated 1,5-pentanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each stage of which has a temperature of 270° C., 280° C., and 290° C., respectively, and react with a copper-zinc-lanthanum catalyst and 2% copper-chromium-aluminum-iron hydroxyphosphate, a copper-zinc-lanthanum catalyst and 10% copper-chromium-aluminum-iron hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 15% copper-chromium-aluminum-iron hydroxyphosphate fixed in each stage of the reactor, with residence times of 10 min, 8 min, and 8 min, respectively, to obtain a mixed product containing δ-valerolactone;

[0124] (3) The mixed product containing δ-valerolactone is cooled to 100° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 96.8% enters a pre-machine buffer tank from a gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 15% of the high-content hydrogen gas with a content of 96.8% returns to the buffer tank of the reaction system through a circulation pipeline, and 85% of the high-content hydrogen gas with a content of 96.8% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0125] (4) The liquid coming out of the gas-liquid separator is split through a diverter valve, 55% of the liquid enters a liquid storage tank to obtain δ-valerolactone with a purity of 98.75%, and 45% of the liquid enters a prepolymerization reactor at a temperature of 115° C. through a delivery pipeline, and reacts for 25 minutes under the action of a six-membered bicyclic guanidine catalyst to generate poly(δ-valerolactone) oligomers;

[0126] (5) The obtained poly (δ-valerolactone) oligomer flows through a vacuum pipe at a temperature of 90°C and a pressure of 4000Pa, and then enters a depolymerization reactor, where it reacts under the action of a boron trioxide acidic solid catalyst at a temperature of 140°C and a vacuum degree of 90Pa. The collected gas phase product enters a collection chamber after condensation, and δ-valerolactone with a purity of 99.946% is obtained.

[0127] Embodiment 19

[0128] (1) 1,6-Hexanediol and hydrogen were respectively discharged at a liquid hourly space velocity of 0.49 h -1 Heqi space speed 86h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with hydroxy copper phosphate-chromium-aluminum-iron fixed in the activation reaction pipeline at 180°C, with a residence time of 90 minutes;

[0129] (2) The activated 1,6-hexanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each section of which has a temperature of 220° C., 240° C., and 275° C., respectively, and react with a copper-zinc-lanthanum catalyst and 1% copper-chromium-aluminum-iron hydroxyphosphate, a copper-zinc-lanthanum catalyst and 5% copper-chromium-aluminum-iron hydroxyphosphate, and a copper-zinc-lanthanum catalyst and 5% copper-chromium-aluminum-iron hydroxyphosphate fixed in each section of the reactor, with residence times of 30 min, 30 min, and 25 min, respectively, to obtain a mixed product containing ε-caprolactone;

[0130] (3) The mixed product containing ε-caprolactone is cooled to 120°C by a heat exchange system, condensed and then enters a gas-liquid separator. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 98.5% enters a pre-machine buffer tank from the gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 18% of the high-content hydrogen gas with a content of 98.5% returns to the buffer tank of the reaction system through a circulation pipeline, and 82% of the high-content hydrogen gas with a content of 98.5% is obtained through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0131] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 60% of the liquid enters a liquid storage tank to obtain ε-caprolactone with a purity of 99.9%, and 40% of the liquid enters a prepolymerization reactor at a temperature of 160° C. through a delivery pipeline, and reacts for 15 minutes under the action of a thiazolium salt catalyst to generate poly(ε-caprolactone) oligomers;

[0132] (5) The obtained poly(ε-caprolactone) oligomer flows through a vacuum pipe at a temperature of 100°C and a pressure of 4000Pa, and then enters a depolymerization reactor, where it reacts under the action of a silica acidic solid catalyst at a temperature of 175°C and a vacuum degree of 250Pa. The collected gas phase products are condensed and then enter a collection chamber to obtain ε-caprolactone with a purity of 99.9932%.

[0133] Embodiment 20

[0134] (1) 1,6-Hexanediol and hydrogen were respectively discharged at a liquid hourly space velocity of 2.5 h -1 Heqi hourly space velocity 150h -1 It enters the activation reaction pipeline through a metering pump and undergoes activation reaction with the hydroxy copper phosphate-chromium-aluminum-iron fixed in the activation reaction pipeline at 200°C, with a residence time of 20 minutes;

[0135] (2) The activated 1,6-hexanediol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, each section of which has a temperature of 240° C., 270° C., and 300° C., respectively, and react with a copper-zinc-cerium catalyst and 1.3% copper-chromium-aluminum-iron hydroxyphosphate, a copper-zinc-cerium catalyst and 6% copper-chromium-aluminum-iron hydroxyphosphate, and a copper-zinc-cerium catalyst and 7% copper-chromium-aluminum-iron hydroxyphosphate fixed in each section of the reactor, with residence times of 20 min, 20 min, and 10 min, respectively, to obtain a mixed product containing ε-caprolactone;

[0136] (3) The mixed product containing ε-caprolactone is cooled to 120°C by a heat exchange system, condensed and then enters a gas-liquid separator. The separated liquid enters a liquid storage tank, and a high-content hydrogen gas with a content of 95% enters a pre-machine buffer tank from the gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 22% of the high-content hydrogen gas with a content of 95% returns to the buffer tank of the reaction system through a circulation pipeline, and 78% of the high-content hydrogen gas with a content of 95% is passed through a hydrogen purification and filling system to obtain a high-purity hydrogen gas with a purity of 99.9999%;

[0137] (4) The liquid coming out of the gas-liquid separator is split by a diverter valve, 30% of the liquid enters a liquid storage tank to obtain ε-caprolactone with a purity of 97.88%, and 70% of the liquid enters a prepolymerization reactor at a temperature of 150° C. through a delivery pipeline, and reacts for 19 minutes under the action of a thiazolium salt catalyst to generate poly(ε-caprolactone) oligomers;

[0138] (5) The obtained poly(ε-caprolactone) oligomer flows through a vacuum pipe at a temperature of 110°C and a pressure of 4000Pa, and then enters a depolymerization reactor, where it reacts under the action of a silica acidic solid catalyst at a temperature of 200°C and a vacuum degree of 400Pa. The collected gas phase products are condensed and then enter a collection chamber to obtain ε-caprolactone with a purity of 99.98%.

Claims

1. A method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols, the method comprising the following steps: (1) The raw material diol and hydrogen are respectively pumped through a metering pump at a liquid hourly space velocity of 0.001-50h -1 Gas hourly space velocity 0.1-1000h -1 Enter the activation reaction pipeline, and stay for activation reaction with the activator fixed in the activation reaction pipeline at 120-280°C for 5-90 minutes; (2) The activated diol and hydrogen enter a three-stage catalytic synthesis reactor through a delivery pipeline, wherein the temperatures of each stage are 180-280° C., 210-300° C., and 230-320° C., respectively, and react with the catalyst system A fixed in the reactor, and the residence reaction times are 1-30 min, 1-30 min, and 5-45 min, respectively, to obtain a mixed product containing lactone; (3) The lactone-containing mixed product is cooled to 30-120° C. by a heat exchange system, and enters a gas-liquid separator after condensation. The separated liquid enters a liquid storage tank, and the high-content hydrogen enters a pre-machine buffer tank from the gas outlet of the gas-liquid separator, and then enters a hydrogen compressor, of which 5-30% of the high-content hydrogen returns to the reaction system buffer tank through a circulation pipeline, and 70-95% of the high-content hydrogen is obtained through a hydrogen purification and filling system to obtain high-purity hydrogen with a purity of 99.9999%; (4) The liquid coming out of the gas-liquid separator is diverted through a diverter valve, 0-100% of the liquid enters a liquid storage tank to obtain high-purity lactone, and 0-100% of the liquid enters a prepolymerization reactor at a temperature of 20-140° C. through a delivery pipeline, and undergoes a polymerization reaction for 10-90 minutes under the action of the catalyst system B to generate polylactone oligomers; (5) The obtained polylactone oligomer flows through a vacuum pipeline at a temperature of 60-140° C. and a pressure of 4000-8000 Pa, and then enters a depolymerization reactor, where it reacts under the action of the catalyst system C at a temperature of 100-200° C. and a vacuum degree of 10-3000 Pa. The collected gas phase product enters a collection chamber after condensation to obtain ultra-high purity lactone.

2. The method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 1, characterized in that The diol described in the production method is any one of 1,4-butanediol, diethylene glycol, 1,5-pentanediol or 1,6-hexanediol.

3. The method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 1 or 2, characterized in that The activator described in the production method is a copper hydroxyphosphate metal salt loaded on a carbon fiber carrier, and the copper hydroxyphosphate metal salt is of the general formula M a x A compound of Cu[(OH)PO4], wherein M is a doping metal selected from at least one metal of Group IIA, Group IIIA, Group IIB, Group VB, Group VIB and Group VIB in the periodic table, and a and x can be any positive numbers but must satisfy ax=2.

4. The method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 1 or 2, characterized in that The diol in the production method is passed through a metering pump at a liquid hourly space velocity of 25-50h -1 Enter the activation reaction pipeline, or through the metering pump at a liquid hourly space velocity of 10-25h -1 Enter the activation reaction pipeline, or through the metering pump at a liquid hourly space velocity of 2-10h -1 Enter the activation reaction pipeline, or through the metering pump at a liquid hourly space velocity of 0.5-2h -1 Entering the activation reaction pipeline, or through a metering pump with a liquid hourly space velocity of 0.001-0.5h -1 Enter the activation reaction pipeline.

5. The method for preparing high-purity and ultra-high-purity lactone and high-purity and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 3, characterized in that The diol in the production method is passed through a metering pump at a liquid hourly space velocity of 25-50h -1 Enter the activation reaction pipeline, or through the metering pump at a liquid hourly space velocity of 10-25h -1 Enter the activation reaction pipeline, or through the metering pump at a liquid hourly space velocity of 2-10h -1 Enter the activation reaction pipeline, or through the metering pump at a liquid hourly space velocity of 0.5-2h -1 Entering the activation reaction pipeline, or through a metering pump with a liquid hourly space velocity of 0.001-0.5h -1 Enter the activation reaction pipeline.

6. The method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 1 or 2, characterized in that: The catalytic system A described in the production method is composed of a copper-zinc-cerium catalyst or a copper-zinc-lanthanum catalyst and an activator, which are composed of a copper compound, a zinc compound and a catalytic promoter as disclosed in the prior art CN 1325162, and the mass ratio of the activator to the catalyst in each fixed catalytic system A in the three-stage catalytic synthesis reactor is 0.01-2%, 0.5-10% and 1-15% respectively; The catalytic system B described in the production method is a catalyst used in the lactone ring-opening polymerization reaction; The catalytic system C described in the production method is at least one of the molecular sieve type solid catalytic system, the acidic solid catalytic system and the alkaline solid catalytic system disclosed in the prior art CN 103880813.

7. The method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 3, characterized in that: The catalytic system A described in the production method is composed of a copper-zinc-cerium catalyst or a copper-zinc-lanthanum catalyst and an activator, which are composed of a copper compound, a zinc compound and a catalytic promoter as disclosed in the prior art CN 1325162, and the mass ratio of the activator to the catalyst in each fixed catalytic system A in the three-stage catalytic synthesis reactor is 0.01-2%, 0.5-10% and 1-15% respectively; The catalytic system B described in the production method is a catalyst used in the lactone ring-opening polymerization reaction; The catalytic system C described in the production method is at least one of the molecular sieve type solid catalytic system, the acidic solid catalytic system and the alkaline solid catalytic system disclosed in the prior art CN 103880813.

8. The method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 4, characterized in that: The catalytic system A described in the production method is composed of a copper-zinc-cerium catalyst or a copper-zinc-lanthanum catalyst and an activator, which are composed of a copper compound, a zinc compound and a catalytic promoter as disclosed in the prior art CN 1325162, and the mass ratio of the activator to the catalyst in each fixed catalytic system A in the three-stage catalytic synthesis reactor is 0.01-2%, 0.5-10% and 1-15% respectively; The catalytic system B described in the production method is a catalyst used in the lactone ring-opening polymerization reaction; The catalytic system C described in the production method is at least one of the molecular sieve type solid catalytic system, the acidic solid catalytic system and the alkaline solid catalytic system disclosed in the prior art CN 103880813.

9. The method for preparing high-purity and ultra-high-purity lactone and high-content hydrogen by dehydrogenation and cyclization of diols according to claim 5, characterized in that: The catalytic system A described in the production method is composed of a copper-zinc-cerium catalyst or a copper-zinc-lanthanum catalyst and an activator, which are composed of a copper compound, a zinc compound and a catalytic promoter as disclosed in the prior art CN 1325162, and the mass ratio of the activator to the catalyst in each fixed catalytic system A in the three-stage catalytic synthesis reactor is 0.01-2%, 0.5-10% and 1-15% respectively; The catalytic system B described in the production method is a catalyst used in the lactone ring-opening polymerization reaction; The catalytic system C described in the production method is at least one of the molecular sieve type solid catalytic system, the acidic solid catalytic system and the alkaline solid catalytic system disclosed in the prior art CN 103880813.

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