A kind of production method and production system of β-isophorone

Abstract

The present invention relates to a kind of production method and production system of β-isophorone, α-isophorone is used as starting material to prepare β-isophorone, and the production system used includes a heater, a gas-liquid separator, a filling column and a distillation tower filled with a catalyst for heating and vaporizing α-isophorone, which are arranged in sequence; the production method includes making α-isophorone enter the gas-liquid separator after the heater is heated and vaporized to obtain gas material, and the gas material enters the filling column and enters the distillation tower after the catalyst is catalyzed to separate, and β-isophorone is obtained. The present invention converts liquid-solid phase reaction into gas-solid phase reaction, greatly reduces the loss of catalyst, avoids the accumulation of catalyst in liquid phase and causes side reactions, and also greatly avoids the instability of the catalyst entering the product to cause the product; in addition, the raw material is first catalyzed by the catalyst, and then separated in the distillation tower, which greatly reduces the occurrence of reverse isomerization reaction in the separation section and improves production efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of fine chemicals, and in particular to a production method and a production system for beta-isophorone. Background Art

[0002] β-isophorone is an important chemical intermediate, which is widely used in the preparation of carotenoids, vitamin E and spices. In the prior art, β-isophorone is prepared by thermal isomerization reaction of α-isophorone. Since α-isophorone has conjugated carbon-carbon double bonds and carbon-oxygen double bonds, the thermodynamic equilibrium is more inclined to α-isophorone. To prepare β-isophorone, only a small amount of β-isophorone in the thermal isomerization equilibrium system can be separated by efficient distillation, so as to move the equilibrium toward the formation of β-isophorone, separate while thermal isomerization, and finally obtain β-isophorone that meets the quality requirements. This leads to the problems of high temperature, low yield, long time and high energy consumption in the preparation of β-isophorone.

[0003] Chinese patent CN1259299C discloses a method for synthesizing β-isophorone, which uses α-isophorone as a raw material, performs an isomerization reaction in a multi-stage reactor when the catalyst and separation agent of the reaction are acidic ceramic materials, and adopts reactive distillation technology to react to obtain β-isophorone. In this method, since the separation stage is also an acidic ceramic material, the reverse isomerization of β-isophorone to α-isophorone is promoted, and the production efficiency is low. At the same time, the acidic ceramic material is filled in the reactor and is easily lost into the distillation tower kettle to cause side reactions.

[0004] Chinese patent CN104649878B discloses a process for continuously synthesizing β-isophorone, using α-isophorone as a starting material, molecular sieve as a catalyst, and adopting reactive distillation technology to carry out isomerization reaction in a reactor, and collecting β-isophorone at the top of the reactor. This method has a low yield, and the catalyst is in contact with the reaction liquid for a long time, which is easy to cause side reactions. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a production method of β-isophorone with less by-products and high yield in view of the deficiencies of the prior art.

[0006] A second object of the present invention is to provide a system for producing β-isophorone with a small amount of by-products and a high yield.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] A method for producing β-isophorone, using α-isophorone as a starting material, and performing an isomerization reaction in a production system under the action of a catalyst to produce β-isophorone, wherein the production system comprises a heater, a gas-liquid separator, a filling column and a distillation tower, which are sequentially arranged to heat and vaporize α-isophorone;

[0009] The catalyst is filled in the packed column;

[0010] The production method comprises the following steps: heating α-isophorone by the heater to vaporize the α-isophorone, and then allowing the α-isophorone to enter the gas-liquid separator for gas-liquid separation to obtain gas material; the gas material enters the filling column, is catalyzed by the catalyst, and then enters the distillation tower for separation to obtain β-isophorone.

[0011] In this application, the catalyst is filled in the filling column, and the filling column and the distillation tower are set independently of each other. The reaction starting raw material is first heated and gasified to obtain a gas material, and the gas material enters the distillation tower after catalysis to obtain β-isophorone. In this way, the first aspect is to convert the liquid-solid phase reaction of α-isophorone thermal isomerization to β-isophorone into a gas-solid phase catalytic reaction, avoid the scouring of the catalyst by the liquid, reduce the loss of the catalyst, and avoid the accumulation of the catalyst in the liquid phase and induce side reactions; secondly, the heavy component in the reaction liquid can flow directly from the liquid phase outlet of the gas-liquid separator into the tower kettle of the distillation tower, and the gas-liquid separator separates the gas material with a very low content of heavy components, which will not be adsorbed on the catalyst carrier and covered on the surface of the active component to cause deactivation, and can extend the service life of the catalyst; thirdly, reduce the by-products formed by the self-polymerization of α-isophorone or β-isophorone due to the loss of the catalyst into the reaction liquid. The catalyst can only accelerate the speed of thermal isomerization of α-isophorone to β-isophorone and reach the equilibrium composition, but does not affect the equilibrium composition. If the catalyst is lost into the distillation column or further brought into the β-isophorone product, when the temperature is lowered, it will also catalyze the conversion of β-isophorone into α-isophorone, affecting the quality of the final product. The gas-solid phase reaction method of the present application can well solve this problem and improve the stability of the final product.

[0012] In some specific embodiments, the production method further comprises inputting the liquid material separated by the gas-liquid separator into the bottom of the distillation tower.

[0013] According to some implementation aspects of the present invention, the production method further comprises putting the starting raw material into the bottom of the distillation tower for heating, and then transporting the material in the bottom of the distillation tower to the heater for heating and gasification;

[0014] Or / and, the production method further comprises conveying the starting raw materials directly to the heater for heating and gasification.

[0015] According to some embodiments of the present invention, the catalyst is a supported p-toluenesulfonate catalyst.

[0016] Supported p-toluenesulfonate catalyst is used as a catalyst for the thermal isomerization reaction to prepare β-isophorone. The p-toluenesulfonate anion has strong nucleophilicity and can quickly attack the 1 # The carbon cation promotes electron rearrangement. p-Toluenesulfonate is also a strong leaving group and easily leaves 1 # The carbon cation leaves to form β-isophorone. Therefore, the use of p-toluenesulfonate as a catalyst for the thermal isomerization of α-isophorone to β-isophorone can quickly promote the thermal isomerization reaction to reach equilibrium. The ratio of α-isophorone and β-isophorone in equilibrium is directly related to the temperature of the thermal isomerization reaction. The higher the temperature of the thermal isomerization reaction, the greater the ratio of β-isophorone, and the lower the temperature of the thermal isomerization reaction, the smaller the ratio of β-isophorone. Compared with the prior art, the present application uses a supported p-toluenesulfonate catalyst to accelerate the speed of the thermal isomerization reaction, so that α-isophorone and β-isophorone quickly reach equilibrium.

[0017] When implementing the technical solution of the present application, directly mixing p-toluenesulfonate with the raw material α-isophorone can also achieve the purpose of improving the conversion efficiency. The present application uses a supported p-toluenesulfonate as a catalyst, which can easily separate the p-toluenesulfonate from the final reaction solution. In this way, on the one hand, the catalyst can be reused, reducing the cost and amount of solid waste of repeated preparation of the catalyst; on the other hand, the adverse effects of strong acid and strong base salts on the stability of β-isophorone or α-isophorone at high temperature are reduced. Preferably, the carrier of the supported p-toluenesulfonate catalyst is a combination of one or more of zeolite and molecular sieve. Using zeolite or molecular sieve as a carrier has the advantages of large particle size, strong adsorption capacity and convenient separation. The prior art also reports that solid acid can be used as a catalyst for isomerization reaction, but there are problems of more by-products and severe corrosion. Zeolite and molecular sieve have weak acidity and can also catalyze the isomerization reaction described in the present application, but there are problems of weak catalytic effect and low production efficiency. In the present invention, p-toluenesulfonate is loaded on a molecular sieve or zeolite, and p-toluenesulfonate microcrystals are uniformly dispersed on the surface and micropores of the molecular sieve or zeolite, thereby increasing the contact points between p-toluenesulfonate and α-isophorone. The molecular sieve or zeolite provides an acidic activation center, and p-toluenesulfonate provides a nucleophilic group, thereby achieving the purpose of synergistically promoting the isomerization reaction.

[0018] The p-toluenesulfonate is an alkali metal p-toluenesulfonate or an alkaline earth metal p-toluenesulfonate. Preferably, the p-toluenesulfonate is a combination of one or more of sodium p-toluenesulfonate and potassium p-toluenesulfonate. Sodium p-toluenesulfonate and potassium p-toluenesulfonate are strong base and strong acid salts, and their aqueous solutions are neutral at room temperature. As a catalyst for thermal isomerization reaction, the adverse effects of strong acidity and strong alkalinity on the stability of α-isophorone or β-isophorone can be minimized.

[0019] Preferably, the loading amount of p-toluenesulfonate in the supported p-toluenesulfonate catalyst is 0.1-1.0wt%. The less the loading amount of p-toluenesulfonate, the more p-toluenesulfonate adsorbed in the internal pores of the carrier, the less likely it is to fall off, the longer the life of the catalyst, but the catalytic activity is reduced; on the contrary, the more the loading amount of p-toluenesulfonate, the more p-toluenesulfonate adsorbed on the surface of the carrier, the easier it is to fall off, the shorter the life of the catalyst, but the initial catalytic activity of the catalyst is strong. In practical applications, it is necessary to avoid the p-toluenesulfonate adsorbed on the carrier from being lost to the reaction solution as much as possible, otherwise the reaction solution is easily to form polymerization by-products when in contact with the free p-toluenesulfonate for a long time. Controlling the loading amount of p-toluenesulfonate in the catalyst to 0.1-1.0wt% can reduce the loss of active ingredients while maintaining the catalyst with the best catalytic activity.

[0020] The preparation method of the catalyst has a great influence on the catalytic activity of the catalyst. The inventors have determined the best catalyst preparation method through a large number of comparative experiments. Preferably, the supported p-toluenesulfonate catalyst is prepared by immersing the carrier in an aqueous p-toluenesulfonate solution, filtering and drying after adsorption saturation.

[0021] More preferably, the drying is carried out at 100-140° C. The preparation method of the catalyst is simple and convenient, the raw materials are easily available, and the catalyst has strong catalytic activity. When the catalyst activity is insufficient, it can be replaced in time.

[0022] To further improve the technical effect, preferably, the number of theoretical plates of the distillation tower is 30 to 60. The design of the distillation tower is critical, and reactive distillation combines chemical reactions with distillation separation. To design a production system with excellent performance, it is first necessary to determine whether the control process of the entire production system belongs to reaction control or distillation control. When it belongs to reaction control, the adjustment of the catalyst and reaction parameters can quickly affect the performance of the entire production system; when it belongs to distillation control, the adjustment of the catalyst and reaction parameters cannot quickly affect the performance of the entire production system. In view of the fact that the present application uses highly efficient supported p-toluenesulfonate as a catalyst for the thermal isomerization reaction, when the number of theoretical plates of the distillation tower is 30 to 60, the production system can be artificially designed into a reaction control state.

[0023] In some specific embodiments, the reflux ratio at the top of the distillation tower is controlled to be 4-8:1.

[0024] Preferably, the temperature of the bottom of the distillation tower is controlled to be 200-250°C, and the pressure in the distillation tower is controlled to be 0.05-0.15MPaA (absolute pressure); further preferably, the temperature of the bottom of the distillation tower is controlled to be the reflux temperature of the reaction material, specifically 220-230°C, and the pressure in the distillation tower is controlled to be normal pressure. The reaction liquid in the bottom of the distillation tower is heated to a reflux temperature of about 220-230°C, and the equilibrium concentration of β-isophorone in the reaction liquid is about 2.5-3.5wt%. The catalyst can speed up the time to reach equilibrium and reduce the formation of by-products at high temperatures. β-isophorone is separated from the reaction liquid by rapid distillation and collected to obtain β-isophorone, and p-toluenesulfonate is loaded on a carrier and does not enter the bottom of the distillation tower. The vaporization amount in the reaction distillation tower is controlled well, and p-toluenesulfonate and other active substances are further ensured not to enter the β-isophorone finished product, and a β-isophorone finished product with stable quality is prepared.

[0025] According to some embodiments of the present invention, the heater has an inlet and an outlet, the gas-liquid separator has an inlet, a gas outlet and a liquid outlet, and the inlet of the gas-liquid separator is connected to the outlet pipeline of the heater; the filling column has an inlet and an outlet, and the inlet of the filling column is connected to the gas outlet pipeline of the gas-liquid separator; the bottom of the distillation tower has a first inlet, a second inlet and an outlet, the second inlet of the bottom is set higher than the first inlet of the bottom, the outlet of the bottom is connected to the inlet of the heater through a first connecting pipe, the first inlet of the bottom is connected to the liquid outlet of the gas-liquid separator through a second connecting pipe, and the second inlet of the bottom is connected to the outlet of the filling column through a third connecting pipe.

[0026] In some embodiments, a first delivery pump is provided on the first connecting pipe.

[0027] In order to make the entire production system run more stably, it is necessary to balance the flow and pressure. Preferably, a second delivery pump and a regulating valve are provided on the second connecting pipe, and the regulating valve is located downstream of the second delivery pump. When the gas-liquid separator has a sufficient height difference relative to the distillation tower kettle, the second delivery pump may not be provided, and the liquid phase can automatically enter the distillation tower kettle through the liquid level difference. However, the provision of a second delivery pump can improve the stability of the entire system. The liquid level signal of the gas-liquid separator is transmitted to the automatic control system to ultimately control the regulating valve to control the valve opening to control the liquid level in the gas-liquid separator at an appropriate position. Generally, the amount of liquid phase in the gas-liquid separator is minimized as much as possible while ensuring the stability of the liquid phase discharge.

[0028] In some embodiments, the production system further includes a feed pipe connected to the first connecting pipe.

[0029] According to some implementation aspects of the present invention, the production system also includes a condenser and a β-isophorone receiving tank, the condenser having an inlet and an outlet, the inlet of the condenser being connected to the top of the distillation tower through a fourth connecting pipe, the outlet of the condenser being connected to the top of the distillation tower through a fifth connecting pipe, and the β-isophorone receiving tank being connected to the fifth connecting pipe through a sixth connecting pipe.

[0030] In some embodiments, the heater is a reboiler.

[0031] The second technical solution adopted by the present invention is: a production system for producing β-isophorone, comprising a heater for heating and vaporizing α-isophorone, a gas-liquid separator, a filling column filled with a catalyst, and a distillation column, wherein the heater has an inlet and an outlet, the gas-liquid separator has an inlet, a gas outlet, and a liquid outlet, and the inlet of the gas-liquid separator is connected to the outlet pipeline of the heater; the filling column has an inlet and an outlet, and the inlet of the filling column is connected to the gas outlet pipeline of the gas-liquid separator; the tower kettle of the distillation tower has a first inlet, a second inlet, and an outlet, the second inlet of the tower kettle is arranged higher than the first inlet of the tower kettle, the outlet of the tower kettle is connected to the inlet of the heater through a first connecting pipe, the first inlet of the tower kettle is connected to the liquid outlet of the gas-liquid separator through a second connecting pipe, and the second inlet of the tower kettle is connected to the outlet of the filling column through a third connecting pipe;

[0032] After the α-isophorone is heated and gasified by the heater, it enters the gas-liquid separator for gas-liquid separation to obtain gas material and liquid material;

[0033] The gaseous material is passed into the filling column, catalyzed by the catalyst, and then enters the distillation tower for separation to obtain the β-isophorone;

[0034] The liquid material is introduced into the bottom of the distillation tower, and the material in the bottom of the distillation tower then enters the heater or is discharged.

[0035] Preferably, the second inlet of the tower kettle is arranged higher than the first inlet of the tower kettle, and the first inlet of the tower kettle is arranged higher than the outlet of the tower kettle.

[0036] In some embodiments, a first delivery pump is disposed on the first connecting pipe; and a second delivery pump is disposed on the second connecting pipe.

[0037] In some embodiments, the production system further includes a feed pipe connected to the first connecting pipe.

[0038] In some embodiments, the distillation tower has 30 to 60 theoretical plates.

[0039] In some embodiments, the production system further includes a condenser and a β-isophorone receiving tank, the condenser having an inlet and an outlet, the inlet of the condenser being connected to the top of the distillation tower via a fourth connecting pipe, the outlet of the condenser being connected to the top of the distillation tower via a fifth connecting pipe, and the β-isophorone receiving tank being connected to the fifth connecting pipe via a sixth connecting pipe.

[0040] In some embodiments, the catalyst is a supported p-toluenesulfonate catalyst.

[0041] In some embodiments, the catalyst carrier is a combination of one or more of zeolite and molecular sieve; and / or the p-toluenesulfonate is a combination of one or more of sodium p-toluenesulfonate and potassium p-toluenesulfonate; and / or the loading amount of p-toluenesulfonate in the supported p-toluenesulfonate catalyst is 0.1 to 1.0 wt%.

[0042] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0043] The production method of the present invention first heats the reaction starting raw materials to gasify them, and the gas materials enter a distillation tower for separation after being catalyzed to obtain β-isophorone. On the one hand, the liquid-solid phase reaction is converted into a gas-solid phase reaction, which greatly reduces the loss of active components in the catalyst, avoids the accumulation of the catalyst in the liquid phase and the induction of side reactions, and also greatly avoids the catalyst entering the product to cause product instability; on the other hand, the raw materials are first catalyzed by the catalyst and then separated in the distillation tower, which greatly reduces the occurrence of reverse isomerization reaction in the separation section and improves production efficiency.

[0044] The content of beta-isophorone obtained by the production method of the invention is as high as over 99wt%, and the yield is also as high as over 95%, and the bottom material rate of the distillation tower is below 4wt%. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a schematic diagram of the structure of the production system used to prepare β-isophorone in an embodiment of the present invention;

[0046] In the figure: 1. heater; 2. gas-liquid separator; 3. packing column; 4. distillation tower; 5. condenser; 6. β-isophorone receiving tank; 7. first delivery pump; 8. second delivery pump; 9. first connecting pipe; 10. second connecting pipe; 11. third connecting pipe; 12. fourth connecting pipe; 13. fifth connecting pipe; 14. sixth connecting pipe; 15. feed pipe; 16. regulating valve. DETAILED DESCRIPTION

[0047] The present application converts the liquid-solid phase reaction into a gas-solid phase reaction, and the filling column filled with the catalyst is set independently from the distillation tower, which greatly reduces the possibility of the catalyst entering the distillation tower kettle. The catalyst entering the distillation tower kettle will cause α-isophorone or β-isophorone to contact the catalyst at high temperature and for a long time, which is easy to cause polymerization side reactions to form high molecular by-products. The catalyst entering the distillation tower kettle may also be brought into the packing layer when the distillation tower operation is abnormal and flooding occurs, and it is further possible to enter the β-isophorone product. When there is a trace amount of catalyst in β-isophorone, it will slowly convert into α-isophorone, reducing the stability of the product.

[0048] A preferred and specific embodiment is as follows:

[0049] Using α-isophorone as a starting material, an isomerization reaction is carried out in a production system under the action of a catalyst to generate β-isophorone, wherein the production system comprises a heater, a gas-liquid separator, a filling column and a distillation tower which are sequentially arranged to heat and vaporize α-isophorone;

[0050] The catalyst is filled in the packed column;

[0051] The production method comprises the steps of feeding the starting raw material into a distillation tower for heating, then conveying the starting raw material to the heater for heating and vaporization, and then entering the gas-liquid separator for gas-liquid separation to obtain liquid material and gas material;

[0052] The liquid material is transported to the bottom of the distillation tower;

[0053] The gaseous material enters the filling column and is catalyzed by the catalyst before entering the distillation tower for separation. The material at the top of the distillation tower is condensed by a condenser, a part of which flows back to the distillation tower, and the other part is output to a β-isophorone receiving tank to obtain a β-isophorone finished product.

[0054] In a further preferred embodiment, the catalyst is a supported p-toluenesulfonate catalyst, which reduces the possibility of p-toluenesulfonate entering the bottom of the distillation tower.

[0055] like Figure 1 As shown, the production method of the present invention can be implemented in the production system shown in the figure.

[0056] like Figure 1 The production system for producing β-isophorone shown includes a heater 1 for heating and vaporizing α-isophorone, a gas-liquid separator 2, a packed column 3 filled with a catalyst, a distillation column 4, a condenser 5 and a β-isophorone receiving tank 6.

[0057] Among them, the heater 1 has an inlet and an outlet, the gas-liquid separator 2 has an inlet, a gas outlet and a liquid outlet, and the inlet of the gas-liquid separator 2 is connected to the outlet pipeline of the heater 1; the filling column 3 has an inlet and an outlet, and the inlet of the filling column 3 is connected to the gas outlet pipeline of the gas-liquid separator 2; the bottom of the distillation tower 4 has a first inlet, a second inlet and an outlet, and the outlet of the bottom of the distillation tower 4 is connected to the inlet of the heater 1 through a first connecting pipe 9, the first inlet of the bottom of the distillation tower 4 is connected to the liquid outlet of the gas-liquid separator 2 through a second connecting pipe 10, and the second inlet of the bottom of the distillation tower 4 is connected to the outlet of the filling column 3 through a third connecting pipe 11.

[0058] The second inlet of the kettle of the distillation tower 4, the first inlet of the kettle of the distillation tower 4, and the outlet of the kettle of the distillation tower 4 are sequentially distributed from top to bottom in the vertical direction.

[0059] The first connecting pipe 9 is provided with a first delivery pump 7 , and the second connecting pipe 10 is provided with a second delivery pump 8 and a regulating valve 16 , respectively. The regulating valve 16 is arranged closer to the distillation tower 4 than the second delivery pump 8 .

[0060] The condenser 5 has an inlet and an outlet. The inlet of the condenser 5 is connected to the top of the distillation tower 4 through a fourth connecting pipe 12, the outlet of the condenser 5 is connected to the top of the distillation tower 4 through a fifth connecting pipe 13, and the β-isophorone receiving tank 6 is connected to the fifth connecting pipe 13 through a sixth connecting pipe 14.

[0061] The production system further comprises a feed pipe 15 , which is connected to the first connecting pipe 9 .

[0062] In this example, heater 1 is a reboiler, which is heated by thermal oil at a temperature of 200-250°C.

[0063] In some specific embodiments, the parameters of the distillation tower 4 are as follows: the tower diameter is 0.6 m, the internal filler is BX stainless steel wire mesh, and the height of the filler layer is 8 m.

[0064] The technical solution of the present invention is described in detail below in conjunction with specific embodiments so that those skilled in the art can better understand and implement the technical solution of the present invention, but the present invention is not limited to the scope of the examples.

[0065] Example 1

[0066] This embodiment adopts Figure 1 The production system shown produces β-isophorone, comprising:

[0067] (1) Preparation of Catalyst

[0068] Add 0.05 kg of potassium p-toluenesulfonate and 25 kg of deionized water to the reactor, start stirring, control the temperature in the reactor to 25-35 ° C to dissolve, and after dissolution, add 5 kg of Molecular sieve, after adsorption for 30 minutes, stop stirring and let it stand overnight.

[0069] The next day, filter and transfer the filter cake directly to a drying tray without washing, place the drying tray in an oven at 30-40°C for 2 hours, then increase the oven temperature to 120°C and continue drying for 4 hours to obtain about 5.03 kg of supported potassium p-toluenesulfonate catalyst, with a potassium p-toluenesulfonate loading of about 0.60 wt%. All the dried catalysts are loaded into the catalyst filling column 3.

[0070] (2) Preparation of β-isophorone

[0071] The number of theoretical plates of the distillation tower 4 is 48. 1200 kg of α-isophorone (α-isophorone content: 99.4 wt%) is added to the bottom of the distillation tower 4, and the pressure in the distillation tower 4 is controlled to be normal pressure; the first delivery pump 7 is turned on, and the reboiler heat transfer oil inlet valve is opened to heat the material at a temperature of 220-230° C.; the second delivery pump 8 is turned on, and the opening of the regulating valve 16 of the liquid level of the gas-liquid separator 2 is automatically controlled so that the liquid level in the gas-liquid separator 2 is kept close to a constant minimum liquid level.

[0072] The steam separated by the gas-liquid separator 2 enters the packed column 3 and then enters the distillation tower 4 after being thermally isomerized by the catalyst. The reflux ratio at the top of the distillation tower 4 is controlled to be 6:1, and the extraction flow rate of β-isophorone is 51 kg / h.

[0073] Finally, 1169 kg of β-isophorone (β-isophorone content: 99.3 wt%, α-isophorone content: 0.21 wt%) was obtained, with a yield of 97.3%. 27 kg of waste material was obtained, and the waste material rate was 2.25 wt%.

[0074] Example 2

[0075] The production system and production method used in this embodiment are basically the same as those in Embodiment 1, except that:

[0076] In step (1), 0.08 kg of potassium p-toluenesulfonate is added to the reaction kettle to obtain about 5.05 kg of supported potassium p-toluenesulfonate catalyst, and the loading amount of potassium p-toluenesulfonate is about 1.0 wt%.

[0077] In step (2), the extraction rate of β-isophorone at the top of the distillation tower 4 is 77 kg / h.

[0078] Finally, 1148 kg of β-isophorone (β-isophorone content: 99.2 wt%, α-isophorone content: 0.25 wt%) was obtained, with a yield of 95.5%. 46 kg of waste material was obtained, and the waste material rate was 3.8 wt%.

[0079] Example 3

[0080] The production system and production method used in this embodiment are basically the same as those in Embodiment 1, except that:

[0081] In step (1), 0.008 kg of potassium p-toluenesulfonate is added to the reaction kettle to obtain about 5.005 kg of supported potassium p-toluenesulfonate catalyst, and the loading amount of potassium p-toluenesulfonate is about 0.1 wt%.

[0082] In step (2), the extraction rate of β-isophorone at the top of the distillation tower 4 is 24 kg / h.

[0083] Finally, 1174 kg of β-isophorone (β-isophorone content: 99.4 wt%, α-isophorone content: 0.22 wt%) was obtained, with a yield of 97.8%. 21 kg of waste material was obtained, and the waste material rate was 1.75 wt%.

[0084] Example 4

[0085] The production system and production method used in this embodiment are basically the same as those in Embodiment 1, except that:

[0086] In step (2), 1200 kg of α-isophorone (α-isophorone content: 99.4 wt%) is added to the bottom of the distillation tower 4, and 1200 kg of α-isophorone (α-isophorone content: 99.4 wt%) is added to the production system through the feed pipe 15, and the feed flow rate in the feed pipe 15 is controlled to be 50 kg / h. The extraction flow rate of β-isophorone at the top of the distillation tower 4 is 48 kg / h.

[0087] Finally, 2342 kg of β-isophorone (β-isophorone content: 99.5 wt%, α-isophorone content: 0.18 wt%) was obtained, with a yield of 97.7%. The waste material was 50 kg, and the waste material rate was 2.1 wt%.

[0088] Example 5

[0089] The production system and production method used in this embodiment are basically the same as those in Embodiment 1, except that:

[0090] In step (2), the reflux ratio at the top of the distillation tower 4 is controlled to be 4:1, and the extraction flow rate of β-isophorone is 82 kg / h.

[0091] Finally, 1172 kg of β-isophorone (β-isophorone content: 99.0 wt%, α-isophorone content: 0.42 wt%) was obtained, with a yield of 97.3%. 24 kg of waste material was obtained, and the waste material rate was 2.0 wt%.

[0092] Example 6

[0093] The production system and production method used in this embodiment are basically the same as those in Embodiment 1, except that:

[0094] In step (1), sodium p-toluenesulfonate is used instead of potassium p-toluenesulfonate, and zeolite is used instead of Molecular sieves were used to obtain about 5.03 kg of supported sodium p-toluenesulfonate catalyst, with a loading amount of about 0.59 wt%.

[0095] In step (2), the withdrawal rate of β-isophorone is 49 kg / h.

[0096] Finally, 1167 kg of β-isophorone (β-isophorone content: 99.2 wt%, α-isophorone content: 0.33 wt%) was obtained, with a yield of 97.1%. 29 kg of waste material was obtained, and the waste material rate was 2.4 wt%.

[0097] Comparative Example 1

[0098] The production system and production method adopted in this comparative example are basically the same as those in Example 1, except that: the first delivery pump is not turned on, and 0.03 kg of potassium p-toluenesulfonate is directly added to the bottom of the distillation tower 4 as a catalyst.

[0099] The β-isophorone extraction flow rate at the top of distillation tower 4 is 62 kg / h.

[0100] Finally, β-isophorone was obtained: 1122 kg (β-isophorone content: 98.9 wt%, α-isophorone content: 0.28 wt%), yield: 93.0%, heap: 73 kg, heap rate: 6.1 wt%.

[0101] Comparative Example 2

[0102] The production system and production method used in this comparative example are basically the same as those in Example 1, except that:

[0103] In step (1), 0.15 kg of potassium p-toluenesulfonate is added to the reaction kettle to obtain about 5.11 kg of supported potassium p-toluenesulfonate catalyst, and the supported amount of potassium p-toluenesulfonate is about 2.15 wt%.

[0104] In step (2), the β-isophorone extraction rate at the top of the distillation tower 4 is 81 kg / h.

[0105] Finally, 1130 kg of β-isophorone (β-isophorone content: 99.0 wt%, α-isophorone content: 0.24 wt%) was obtained, with a yield of 93.8%. 64 kg of waste material was obtained, and the waste material rate was 5.3 wt%.

[0106] Comparative Example 3

[0107] The production system and production method adopted in this comparative example are basically the same as those in Example 1, except that: the first delivery pump 7 is not turned on, and the loaded potassium p-toluenesulfonate is filled in the distillation tower 4.

[0108] The withdrawal rate of β-isophorone is 58 kg / h.

[0109] Finally, 1139 kg of β-isophorone (β-isophorone content: 99.1 wt%, α-isophorone content: 0.2 wt%) was obtained, with a yield of 94.6%. 53 kg of waste material was obtained, and the waste material rate was 4.4 wt%.

[0110] Comparative Example 4

[0111] The production system and production method used in this comparative example are basically the same as those in Example 1, except that:

[0112] Fill the column with 5 kg of Molecular sieve.

[0113] The withdrawal rate of β-isophorone is 6 kg / h.

[0114] Finally, 874 kg of β-isophorone (β-isophorone content: 98.4 wt%, α-isophorone content: 0.57 wt%) was obtained, with a yield of 72.1%. 312 kg of heaps were obtained, with a heap rate of 26.0 wt%.

[0115] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

[0116] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

Claims

1. A method for producing β-isophorone, using α-isophorone as a starting material, and performing an isomerization reaction in a production system under the action of a catalyst to produce β-isophorone, characterized in that: The production system comprises a heater, a gas-liquid separator, a filling column and a distillation tower which are arranged in sequence to heat and vaporize α-isophorone; The catalyst is filled in the packed column; The production method comprises the steps of heating and vaporizing α-isophorone by the heater, and then allowing the α-isophorone to enter the gas-liquid separator for gas-liquid separation to obtain a gas material, and the gas material enters the filling column, is catalyzed by the catalyst, and then enters the distillation tower for separation to obtain β-isophorone; The catalyst is a supported p-toluenesulfonate catalyst; The catalyst carrier is a combination of one or more of zeolite and molecular sieve; The loading amount of p-toluenesulfonate in the supported p-toluenesulfonate catalyst is 0.1-1.0 wt %.

2. The method for producing β-isophorone according to claim 1, characterized in that: The production method further comprises inputting the liquid material separated by the gas-liquid separator into the bottom of the distillation tower.

3. The method for producing β-isophorone according to claim 1, characterized in that: The production method further comprises putting the starting raw material into the bottom of the distillation tower for heating, and then transporting the material in the bottom of the distillation tower to the heater for heating and gasification; Or / and, the production method further comprises conveying the starting raw materials directly to the heater for heating and gasification.

4. The method for producing β-isophorone according to claim 1, characterized in that: The reflux ratio at the top of the distillation tower is controlled to be 4-8:1; and / or the number of theoretical plates of the distillation tower is controlled to be 30-60; and / or the bottom temperature of the distillation tower is controlled to be 200-250°C, and the pressure in the distillation tower is controlled to be 0.05-0.15MPaA.

5. The method for producing β-isophorone according to claim 4, characterized in that: The bottom temperature of the distillation tower is controlled to be 220-230° C., and the pressure in the distillation tower is controlled to be normal pressure.

6. The method for producing β-isophorone according to claim 1, characterized in that: The p-toluenesulfonate is a combination of one or more of sodium p-toluenesulfonate and potassium p-toluenesulfonate.

7. The method for producing β-isophorone according to claim 1, characterized in that: The supported p-toluenesulfonate catalyst is prepared by immersing the carrier in a p-toluenesulfonate aqueous solution, filtering and drying after saturation adsorption.

8. The method for producing β-isophorone according to any one of claims 1 to 4, characterized in that: The heater has an inlet and an outlet, the gas-liquid separator has an inlet, a gas outlet and a liquid outlet, and the inlet of the gas-liquid separator is connected to the outlet pipeline of the heater; the filling column has an inlet and an outlet, and the inlet of the filling column is connected to the gas outlet pipeline of the gas-liquid separator; the bottom of the distillation tower has a first inlet, a second inlet and an outlet, the second inlet of the bottom is set higher than the first inlet of the bottom, the outlet of the bottom is connected to the inlet of the heater through a first connecting pipe, the first inlet of the bottom is connected to the liquid outlet of the gas-liquid separator through a second connecting pipe, and the second inlet of the bottom is connected to the outlet of the filling column through a third connecting pipe.

9. The method for producing β-isophorone according to claim 8, characterized in that: The first connecting pipe is provided with a first delivery pump; the second connecting pipe is provided with a second delivery pump; and / or, the second connecting pipe is provided with a regulating valve; and / or, the production system further includes a feed pipe, which is connected to the first connecting pipe.

10. The method for producing β-isophorone according to claim 8, characterized in that: The production system also includes a condenser and a β-isophorone receiving tank, the condenser having an inlet and an outlet, the inlet of the condenser being connected to the top of the distillation tower through a fourth connecting pipe, the outlet of the condenser being connected to the top of the distillation tower through a fifth connecting pipe, and the β-isophorone receiving tank being connected to the fifth connecting pipe through a sixth connecting pipe.

11. A production system for producing β-isophorone, characterized in that: The production system comprises a heater for heating and vaporizing α-isophorone, a gas-liquid separator, a filling column filled with a catalyst, and a distillation column, wherein the heater has an inlet and an outlet, the gas-liquid separator has an inlet, a gas outlet, and a liquid outlet, and the inlet of the gas-liquid separator is connected to the outlet pipeline of the heater; the filling column has an inlet and an outlet, and the inlet of the filling column is connected to the gas outlet pipeline of the gas-liquid separator; the tower kettle of the distillation tower has a first inlet, a second inlet, and an outlet, the second inlet of the tower kettle is arranged higher than the first inlet of the tower kettle, the outlet of the tower kettle is connected to the inlet of the heater through a first connecting pipe, the first inlet of the tower kettle is connected to the liquid outlet of the gas-liquid separator through a second connecting pipe, and the second inlet of the tower kettle is connected to the outlet of the filling column through a third connecting pipe; After the α-isophorone is heated and gasified by the heater, it enters the gas-liquid separator for gas-liquid separation to obtain gas material and liquid material; The gaseous material is passed into the filling column, catalyzed by the catalyst, and then enters the distillation tower for separation to obtain the β-isophorone; The liquid material is introduced into the bottom of the distillation tower, and the material in the bottom of the distillation tower then enters the heater or is discharged.

12. The β-isophorone production system according to claim 11, characterized in that: The first connecting pipe is provided with a first delivery pump; the second connecting pipe is provided with a second delivery pump; and / or, The second connecting pipe is provided with a regulating valve; and / or, The production system further comprises a feed pipe, wherein the feed pipe is connected to the first connecting pipe; and / or, The number of theoretical plates of the distillation tower is 30 to 60; and / or, The production system also includes a condenser and a β-isophorone receiving tank, the condenser having an inlet and an outlet, the inlet of the condenser being connected to the top of the distillation tower through a fourth connecting pipe, the outlet of the condenser being connected to the top of the distillation tower through a fifth connecting pipe, and the β-isophorone receiving tank being connected to the fifth connecting pipe through a sixth connecting pipe.

13. The β-isophorone production system according to claim 11, characterized in that: The catalyst is a supported p-toluenesulfonate catalyst.

14. The β-isophorone production system according to claim 13, characterized in that: The carrier of the catalyst is a combination of one or more of zeolite and molecular sieve; and / or the p-toluenesulfonate is a combination of one or more of sodium p-toluenesulfonate and potassium p-toluenesulfonate; and / or the loading amount of p-toluenesulfonate in the supported p-toluenesulfonate catalyst is 0.1-1.0wt%.

Images