WO2023070262A1 - DEVICE AND METHOD FOR PRODUCING CUMENE BY HYDROGENOLYSIS OF α,α-DIMETHYLBENZYL ALCOHOL - Google Patents

Abstract

The present application relates to a device and method for preparing cumene by the hydrogenolysis of α,α-dimethylbenzyl alcohol. The device comprises a first hydrogenation reactor, a flash separator, a second hydrogenation reactor and a heavy component removal device, which are connected in sequence; a raw material inlet of the first hydrogenation reactor is provided with an organic acid adding device, and a reactant outlet of the first hydrogenation reactor is provided with the flash separator; a liquid phase product obtained from the flash separator flows into the second hydrogenation reactor. The described method is carried out in the device. In the present application, by mixing a raw material containing α,α-dimethylbenzyl alcohol with an organic acid, the acidity of the reaction system of a first hydrogenation reaction is increased such that the first hydrogenation reaction can be carried out at a lower temperature, which reduces the single-use consumption of cumene, and also prevents the problem of increased by-products caused by a rise in temperature.

Description

A device and method for producing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol technical field

The application belongs to the technical field of propylene oxide preparation, and relates to a method for preparing cumene, in particular to a device and method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol.

Background technique

Propylene oxide (PO) is an important organic chemical raw material, mainly used in the production of polyether polyols, propylene glycol, propylene glycol ether, etc. Currently, PO commercial production methods mainly include chlorohydrin method, co-oxidation method and hydrogen peroxide direct oxidation method (HPPO method). Among them, the chlorohydrin method has the disadvantages of serious equipment corrosion, large amount of waste water and solid waste, and serious environmental pollution. The hydrogen peroxide direct oxidation method (HPPO method) has the defects of high hydrogen peroxide cost and poor economy.

Co-oxidation method, also known as co-production method or indirect oxidation method, is to generate propylene oxide through the reaction of organic peroxide and propylene, and at the same time by-product organic alcohol, mainly including PO/TBA (MTBE), PO/SM and PO/CHP kind of craft. Among them, PO/TBA (MTBE) has the disadvantages of long process and large equipment investment; PO/SM method has the disadvantages of long process flow, large equipment investment and large amount of waste water and waste gas.

The PO/CHP process is a cumene co-oxidation method, which includes three core reactions of cumene peroxidation, propylene epoxidation and α,α-dimethylbenzyl alcohol (α-Cumyl Alcohol, CA) hydrogenolysis and related refining process. The peroxidation reaction of propylene and cumene produces PO and α,α-dimethylbenzyl alcohol, and the hydrogenolysis of α,α-dimethylbenzyl alcohol produces cumene, and the cumene undergoes peroxidation reaction after purification to obtain Cumene hydroperoxide, thereby realizing the recycling of cumene.

Compared with other co-oxidation processes, the cumene co-oxidation process has short process routes, less equipment investment and no co-products. However, the liquid-phase hydrogenolysis reaction of α,α-dimethylbenzyl alcohol to generate cumene is difficult to control, and the dehydration of dimethyl benzyl alcohol to generate α-methylstyrene (AMS) is easy to polymerize, and at the same time, there is excessive hydrogenation The defect that it is difficult to separate isopropylcyclohexane from the product is generated.

CN 112473734A discloses a method for preparing cumene by reactive distillation coupling hydrogenation reaction of dimethyl benzyl alcohol, comprising the following steps: the dimethyl benzyl alcohol stream containing cumene enters the reactive distillation column, and the heavy component impurities Extracted from the bottom of the tower, the enriched dimethyl benzyl alcohol enters the reaction rectification section packed with acidic catalyst, where the dimethyl benzyl alcohol is dehydrated to generate AMS and water; AMS, water and cumene are separated by rectification The AMS, water and cumene at the top of the tower pass through the coalescer to separate water, and the stream containing cumene and AMS is hydrogenated into cumene through the hydrogenation reactor. It solves the problem of poor selectivity, poor stability and short lifespan of the direct hydrogenolysis reaction catalyst of dimethyl benzyl alcohol by making the acidic catalyst a cationic acidic resin, metal oxide, acidic zeolite molecular sieve, solid heteropolyacid, and acidic ionic liquid immobilized catalyst. problem with high cost.

CN 113070060A discloses a catalyst for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, its preparation method and application. The preparation method comprises the following steps: (1) configuring alkaline earth metal compound solution and two palladium source solutions with pH<2 and pH≥3; , aging, filtering, drying and roasting; (3) two kinds of palladium source solutions are impregnated in two steps, and aging, washing, drying and roasting steps are carried out after each impregnation. Different palladium sources are used to impregnate the carrier step by step to solve the problem of low utilization rate of active components in the hydrogenolysis of α,α-dimethylbenzyl alcohol, and at the same time reduce the reaction temperature, inhibit the occurrence of side reactions, and improve the catalyst performance. selectivity.

CN 113058628A discloses a Pd-C catalyst for preparing cumene by hydrogenolysis and a preparation method thereof. The catalyst comprises the following components by weight fraction: a) 0.057-2.3% palladium Pd; b) 97.7-99.943% Any one or more of the carrier activated carbon, zirconium dioxide or titanium dioxide. The preparation method includes carrier treatment, active component loading, drying, and roasting to prepare the catalyst. The preparation method improves the dispersion of the catalyst by controlling the particle size of the active component, suppresses the generation of cumylcyclohexane, and improves the The conversion rate of dimethyl benzyl alcohol and the yield of cumene.

Although the above method can improve the conversion rate of dimethyl benzyl alcohol and the yield of cumene in the preparation process of the cumene co-oxidation method, the main improvement points are the improvement of the catalyst used, and do not involve p-cumene co-oxidation. Improvement of related processes in oxidation method. Therefore, a process improvement is provided to increase the conversion rate of dimethyl benzyl alcohol and the yield of cumene, which can further reduce the cost of preparing cumene by co-oxidation of cumene.

Contents of the invention

The application provides a device and method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol. The method performs two-stage hydrogenolysis on α,α-dimethylbenzyl alcohol, the first stage of hydrogenolysis can be carried out at a lower temperature, thereby reducing the energy consumption of hydrogenolysis, and then cooperates with the second stage of hydrogenolysis, The conversion rate of the α,α-dimethylbenzyl alcohol is guaranteed, the unit consumption of cumene is reduced on the whole, and the economical efficiency of the cumene co-oxidation recycling process is improved.

In the first aspect, the application provides a device for producing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, the device includes a first hydrogenation reactor, a flash separator, a second hydrogenation reactor connected in sequence Hydrogen reactor and weight removal device.

The raw material inlet of the first hydrogenation reactor is provided with an organic acid adding device.

The reactant outlet of the first hydrogenation reactor is provided with a flash separator, wherein the liquid phase product obtained by the flash separator flows into the second hydrogenation reactor.

The α,α-dimethylbenzyl alcohol is subjected to the first hydrogenation reaction in the first hydrogenation reactor, and the second hydrogenation reaction is performed in the second hydrogenation reactor. The product of the first hydrogenation reaction is separated from moisture and organic acids in a flash separator. The second hydrogenation product is de-heavy processed in the de-heavy device to obtain the heavy component containing bibenzyl and the light component cumene.

The present application improves the acidity of the reaction system in the first hydrogenation reactor by installing an organic acid addition device at the raw material inlet of the first hydrogenation reactor, thereby reducing the temperature required for the first hydrogenation reaction, not only reducing the The unit consumption of propylbenzene can also reduce the generation of by-product benzene ring hydrogenation products.

Preferably, the heavy component outlet of the deweighting device is connected to the feed inlet of the second hydrogenation reactor.

The second hydrogenation product undergoes weight removal treatment by the weight removal device to obtain a heavy component containing 15-45wt% bibenzyl, and realizes the recovery of bibenzyl by connecting the outlet of the heavy component with the feed port of the second hydrogenation reactor Utilize, convert bibenzyl into cumene through the second hydrogenation reaction, reduce the material consumption of cumene caused by generating by-products.

Preferably, the first hydrogenation reactor is provided with a first catalyst; the first catalyst is a Pd-A/SiO ₂ -Al ₂ O ₃ catalyst, wherein A is B ₂ O ₃ , La ₂ O ₃ , Any one or combination of at least two of CeO ₂ or MnO ₂ , typical but non-limiting combinations include the combination of B ₂ O ₃ and La ₂ O ₃ , the combination of La ₂ O ₃ and CeO ₂ , the combination of CeO ₂ and Combination of MnO ₂ , combination of B ₂ O ₃ , La ₂ O ₃ and CeO ₂ , combination of La ₂ O ₃ , CeO ₂ and MnO ₂ , or combination of B ₂ O ₃ , La ₂ O ₃ , CeO ₂ and MnO ₂ combination.

The SiO ₂ -Al ₂ O ₃ in the first catalyst has strong acidity, and the addition of additive A can further increase the acidity of the first catalyst, so as to cooperate with the organic acid given by the organic acid addition device, which is the second A hydrogenation reactor is capable of reacting at a lower hydrogenation temperature.

Preferably, based on the mass percentage of the first catalyst being 100 wt%, the mass percentage of Pd is 0.05-2 wt%, such as 0.05 wt%, 0.1 wt%, 0.2 wt%, 0.5 wt%, 0.8wt%, 1wt%, 1.2wt%, 1.5wt% or 2wt%, but not limited to the listed values, other unlisted values within the range of values are also applicable.

Preferably, based on the mass percentage of the first catalyst as 100 wt%, the mass percentage of A is 1-4 wt%, such as 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt% , 3.5wt% or 4wt%, but not limited to the listed values, other unlisted values within the range of values are also applicable.

Preferably, based on the mass percentage of the first catalyst being 100 wt%, the mass percentage of the carrier SiO ₂ -Al ₂ O ₃ is 94-98.95 wt%, such as 94 wt%, 94.5 wt%, 95 wt%, 96wt%, 97wt%, 98wt% or 98.95wt%, but not limited to the listed values, other unlisted values within the range of values are also applicable.

The sum of the mass percentages of Pd, A and the carrier SiO ₂ -Al ₂ O ₃ in the first catalyst is 100 wt%.

Preferably, SiO ₂ in the carrier SiO ₂ -Al ₂ O ₃ is 30-65wt% of the total mass of the carrier, for example, it can be 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt% or 65wt% , but not limited to the listed values, other unlisted values within the range of values are also applicable, and the balance is Al ₂ O ₃ .

The preparation method of the first catalyst Pd-A/SiO ₂ -Al ₂ O ₃ catalyst described in this application comprises the following steps:

(a) Mix aluminum source, silicon source and organic solvent, heat up to 40-60°C, then add additive A for hydrolysis, add pH regulator dropwise during hydrolysis to control pH to 8-10, and perform aging after hydrolysis to obtain aging slurry;

(b) The aging slurry obtained in step (a) is filtered, dried and roasted to obtain a carrier containing auxiliary agent A;

(c) The carrier containing the auxiliary agent A obtained in step (b) is impregnated into the Pd source solution, and dried and calcined to obtain the first catalyst.

The aluminum source in step (a) includes but not limited to aluminum isopropoxide; the silicon source in step (a) includes but not limited to ethyl silicate; the pH regulator in step (a) includes but not limited to ammonia water.

Preferably, the hydrolysis temperature in step (a) is 40-60°C, such as 40°C, 42°C, 45°C, 48°C, 50°C, 54°C, 56°C or 60°C, but not limited to the listed The numerical value of , other unlisted numerical values in the numerical range are also applicable.

Preferably, the hydrolysis time in step (a) is 0.5-2h, for example, it can be 0.5h, 0.8h, 1h, 1.2h, 1.5h, 1.6h, 1.8h or 2h, but not limited to the listed values, Other unrecited values within the range of values also apply.

Preferably, ultrasonic treatment is used during the hydrolysis in step (a). Ultrasonic treatment can disperse additive A evenly, thus helping to improve the hydrolysis effect.

Preferably, the aging temperature in step (a) is 50-70°C, for example, it can be 50°C, 55°C, 60°C, 65°C or 70°C, but it is not limited to the listed values, and other values are not listed within the range values are also applicable.

Preferably, the aging time in step (a) is 2-4h, such as 2h, 2.5h, 3h, 3.5h or 4h, but not limited to the listed values, other unlisted values within the range of values are also applicable .

The platinum source in step (c) is a conventional soluble platinum source in the art, including but not limited to chloroplatinic acid.

The impregnation in step (c) is carried out under the condition of reflux, and the impregnation temperature is 60-80°C, for example, it can be 60°C, 65°C, 70°C, 75°C or 80°C, but it is not limited to the listed values. Other unlisted values within the range are also applicable; the time is 2-4h, such as 2h, 2.5h, 3h, 3.5h or 4h, but not limited to the listed values, other unlisted values within the range of values are also applicable.

After the impregnation in step (c), air-dry, wash, and then dry and roast to obtain the first catalyst.

Preferably, the second hydrogenation reactor is provided with a second catalyst; the second catalyst is a Pd/C catalyst.

Preferably, based on 100 wt% of the second catalyst, the mass percentage of Pd is 0.05-2 wt%, such as 0.05 wt%, 0.1 wt%, 0.2 wt%, 0.5 wt%, 0.8 wt%, 1wt%, 1.2wt%, 1.5wt% or 2wt%, but not limited to the listed values, other unlisted values in the numerical range are also applicable; the mass percentage of carrier C is 98-99.95wt%, for example, it can be 98wt% , 98.5wt%, 99wt%, 99.5wt% or 99.95wt%, but not limited to the listed values, other unlisted values within the range of values are also applicable.

The sum of the mass percents of Pd and carrier C in the second catalyst is 100wt%.

The preparation method of the second catalyst Pd/C described in the application comprises the steps:

(1) mixing activated carbon and nitric acid, washing and drying after heating under reflux, obtains a modified carrier;

(II) The modified carrier obtained in step (I) is impregnated into the Pd source solution, and dried and calcined to obtain the second catalyst.

Preferably, the concentration of nitric acid in step (I) is 12-16wt%, for example, it can be 12wt%, 13wt%, 14wt%, 15wt% or 16wt%, but not limited to the numerical values listed, other not listed in the numerical range values are also applicable.

Preferably, the temperature of reflux heating in step (I) is 60-80°C, for example, it can be 60°C, 65°C, 70°C, 75°C or 80°C, but it is not limited to the listed values, and other values within the range are not The listed values are also applicable; the time is 2-4h, for example, 2h, 2.5h, 3h, 3.5h or 4h, but not limited to the listed values, other unlisted values within the range of values are also applicable.

The end point of the washing described in step (I) is to make the washing solution neutral.

The platinum source in step (II) is a conventional soluble platinum source in the art, including but not limited to chloroplatinic acid.

Preferably, the impregnation in step (II) is carried out under reflux conditions, and the impregnation temperature is 60-80°C, such as 60°C, 65°C, 70°C, 75°C or 80°C, but not limited to the listed Numerical values, other unlisted numerical values in the numerical range are also applicable; the time is 2-4h, for example, it can be 2h, 2.5h, 3h, 3.5h or 4h, but not limited to the listed numerical values, other unlisted numerical values in the numerical range The same applies.

The flash separator described in the first aspect of the present application is used to flash remove the moisture and organic acid in the first hydrogenation product, so as to prevent the organic acid from entering the second hydrogenation reactor. As a preferred technical scheme, the organic acid obtained by the flash separator is used back in the first hydrogenation reactor.

In a second aspect, the present application provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, the method comprising the following steps:

(1) mixing raw materials containing α,α-dimethylbenzyl alcohol with organic acid and hydrogen, performing a first hydrogenation reaction, flashing and separating water and organic acid, and obtaining a first hydrogenation product;

(2) The first hydrogenated product obtained in step (1) is mixed with hydrogen to carry out a second hydrogenation reaction, and the obtained second hydrogenated product is subjected to deheavy treatment to obtain a cumene product.

In this application, the acidity of the reaction system of the first hydrogenation reaction is improved by mixing the raw material containing α,α-dimethylbenzyl alcohol with an organic acid, so that the first hydrogenation reaction can be carried out at a lower temperature, which not only reduces the The unit consumption of propylene benzene also avoids the problem of increasing by-products caused by temperature rise.

Preferably, the raw material containing α,α-dimethylbenzyl alcohol in step (1) includes: 18-28wt% α,α-dimethylbenzyl alcohol, ≤0.05wt% propylene oxide, ≤0.3wt% The cumene hydroperoxide, the phenol of ≤0.2wt%, the balance is cumene.

In the raw material containing α,α-dimethylbenzyl alcohol, the mass percentage of α,α-dimethylbenzyl alcohol is 18-28wt%, for example, it can be 18, 20, 21, 24, 25, 27 or 28, But not limited to the listed values, other unlisted values within the range of values are also applicable.

In the α,α-dimethylbenzyl alcohol-containing raw material, the mass percentage of propylene oxide is ≤500ppm, for example, it can be 100ppm, 200ppm, 300ppm, 400ppm or 500ppm, but not limited to the listed values, other values within the range Values not listed also apply.

In the raw material containing α,α-dimethylbenzyl alcohol, the mass percentage of cumyl hydroperoxide is ≤3000ppm, such as 20ppm, 100ppm, 200ppm, 300ppm, 500ppm, 1000ppm, 1500ppm, 2000ppm, 2500ppm or 3000ppm, but not limited to the listed values, other unlisted values within the range of values are also applicable.

In the raw material containing α,α-dimethylbenzyl alcohol, the mass percentage of phenol is ≤2000ppm, such as 50ppm, 100ppm, 200ppm, 500ppm, 1000ppm, 1200ppm, 1500ppm, 1600ppm, 1800ppm or 2000ppm, but not limited to Listed values, other unlisted values within the range of values also apply.

Preferably, the organic acid described in step (1) includes any one or a combination of at least two of benzenesulfonic acid, o-toluenesulfonic acid, or p-toluenesulfonic acid. Typical but non-limiting combinations include benzenesulfonic acid and o-toluenesulfonic acid. A combination of toluenesulfonic acid, a combination of o-toluenesulfonic acid and p-toluenesulfonic acid, a combination of benzenesulfonic acid and p-toluenesulfonic acid, or a combination of benzenesulfonic acid, o-toluenesulfonic acid and p-toluenesulfonic acid.

Preferably, the amount of organic acid added in step (1) is 0.01-0.2wt% of the raw material containing α,α-dimethylbenzyl alcohol, for example, it can be 0.01wt%, 0.02wt%, 0.05wt%, 0.08wt% %, 0.1wt%, 0.12wt%, 0.15wt%, 0.18wt% or 0.2wt%, but not limited to the listed values, other unlisted values within the range of values are also applicable.

In the present application, by adding an organic acid during the first hydrogenation reaction, the temperature required for the first hydrogenation reaction can be reduced, effectively reducing the generation of by-products. When the amount of organic acid added is small, the purpose of reducing the temperature of the first hydrogenation reaction cannot be achieved; when the amount of organic acid added is large, the temperature of the first hydrogenation reaction cannot be further reduced, and the subsequent flash separation burden.

Preferably, the catalyst used in the first hydrogenation reaction in step (1) is the first catalyst.

The first catalyst is a Pd-A/SiO ₂ -Al ₂ O ₃ catalyst, wherein A is any one or a combination of at least two of B ₂ O ₃ , La ₂ O ₃ , CeO ₂ or MnO ₂ , typically But non-limiting combinations include _the combination of _{B2O3 and La2O3} , the combination of _{La2O3 and CeO2} , _the combination _{of CeO2} and _MnO2 , the combination of _B2O3 , _La2O3 and _CeO2 combination, a combination of La ₂ O ₃ , CeO ₂ and MnO ₂ , or a combination of B ₂ O ₃ , La ₂ O ₃ , CeO ₂ and MnO ₂ .

The SiO ₂ -Al ₂ O ₃ in the first catalyst has strong acidity, and the addition of additive A can further increase the acidity of the first catalyst, so as to cooperate with the organic acid given by the organic acid addition device, which is the second A hydrogenation reaction can be carried out at a lower hydrogenation temperature.

Preferably, the gauge pressure of the first hydrogenation reaction in step (1) is 1.5-3MPa, such as 1.5MPa, 1.8MPa, 2MPa, 2.5MPa, 2.8MPa or 3MPa, but not limited to the listed values, the values Other unlisted values in the range are also applicable; the temperature is 120-140°C, for example, it can be 120°C, 125°C, 130°C, 135°C or 140°C, but not limited to the listed values, other unlisted values within the range Numerical values also apply.

Preferably, the liquid hourly space velocity of the first hydrogenation reaction in step (1) is 1-3h ^-1 , such as 1h ^-1 , 1.5h ^-1 , 2h ^-1 , 2.5h ^-1 or 3h ^-1 , But not limited to the listed values, other unlisted values within the range of values are also applicable.

Preferably, the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol in the first hydrogenation reaction in step (1) is (100-300):1, for example, it can be 100:1, 150:1, 200 :1, 250:1 or 300:1, but not limited to the listed values, other unlisted values within the value range are also applicable.

The volume ratio of hydrogen to α,α-dimethylbenzyl alcohol in the first hydrogenation reaction described in this application refers to the ratio of hydrogen to α,α-dimethylbenzyl alcohol in the raw material containing α,α-dimethylbenzyl alcohol volume ratio. Exemplarily, if the volume ratio of hydrogen to the raw material containing α,α-dimethylbenzyl alcohol during the first hydrogenation reaction in step (1) is 100:100, in the raw material containing α,α-dimethylbenzyl alcohol If the volume concentration of α,α-dimethylbenzyl alcohol is 1%, the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is 100:1.

Preferably, the catalyst used in the second hydrogenation reaction in step (2) is a second catalyst; the second catalyst is a Pd/C catalyst.

Preferably, the gauge pressure of the second hydrogenation reaction in step (2) is 1.5-3MPa, such as 1.5MPa, 1.8MPa, 2MPa, 2.5MPa, 2.8MPa or 3MPa, but not limited to the listed values, the values Other unlisted values in the range are also applicable; the temperature is 150-170°C, for example, it can be 150°C, 155°C, 160°C, 165°C or 170°C, but not limited to the listed values, other unlisted values within the range Numerical values also apply.

Preferably, the liquid hourly space velocity of the second hydrogenation reaction in step (2) is 1-3h ^-1 , such as 1h ^-1 , 1.5h ^-1 , 2h ^-1 , 2.5h ^-1 or 3h ^-1 , But not limited to the listed values, other unlisted values within the range of values are also applicable.

The hydrogen required for the second hydrogenation reaction in step (2) of the present application comes from the first hydrogenation reaction.

Preferably, the light component obtained from the deweighting treatment in step (2) is a cumene product, and the heavy component obtained is returned to be mixed with the first hydrogenation product, and then the second hydrogenation reaction is performed.

After the first hydrogenation reaction and the second hydrogenation reaction described in this application, the composition of the heavy component obtained after deweighting treatment is: 15-45wt% of bibenzyl and ≤0.1wt% of α-styrene polymer, and the rest The amount is cumene.

The present application realizes the recovery and utilization of bibenzyl by reusing the heavy components containing bibenzyl. Since bibenzyl can be hydrogenated to generate cumene, it can reduce the consumption of cumene caused by the generation of by-products.

Preferably, in the mixture obtained by mixing the heavy component and the first hydrogenation product, the mass percentage of bibenzyl is 0.01-3wt%, such as 0.01wt%, 0.05wt%, 0.1wt%, 0.3wt%, 0.5wt% %, 0.8wt%, 1wt%, 1.2wt%, 1.5wt%, 2wt%, 2.5wt% or 3wt%, but not limited to the numerical values listed, other unlisted numerical values in the numerical range are also applicable, preferably 0.1- 1.5 wt%.

As a preferred technical solution of the method described in the second aspect, the method includes the following steps:

(1) The raw material containing α,α-dimethylbenzyl alcohol is mixed with organic acid and hydrogen, and the first hydrogenation reaction is carried out by using the first catalyst, and the water and organic acid are separated by flash evaporation to obtain the first hydrogenation product; the organic The amount of acid added is 0.01-0.2wt% of the raw material containing α,α-dimethylbenzyl alcohol; the gauge pressure of the first hydrogenation reaction is 1.5-3MPa, the temperature is 120-140°C, and the liquid hourly space velocity is 1 -3h ^-1 , the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is (100-300):1;

(2) The first hydrogenation product obtained in step (1) is mixed with hydrogen, and the second hydrogenation reaction is carried out by using the second catalyst, and the second hydrogenation product is deheavy-treated to obtain the cumene product; the second hydrogenation The gauge pressure of the reaction is 1.5-3MPa, the temperature is 150-170°C, and the liquid hourly space velocity is 1-3h ^-1 .

Compared with the prior art, the present application has the following beneficial effects:

(1) The present application improves the acidity of the reaction system in the first hydrogenation reactor by setting an organic acid addition device at the raw material inlet of the first hydrogenation reactor, thereby reducing the temperature required for the first hydrogenation reaction, not only The unit consumption of cumene is reduced, and the generation of by-product benzene ring hydrogenation products can also be reduced;

(2) The application realizes the recovery and utilization of bibenzyl by connecting the heavy component outlet with the feed port of the second hydrogenation reactor, and converts bibenzyl into cumene by the second hydrogenation reaction, reducing the production of by-products. The cumene consumption caused by the product;

(3) The SiO ₂ -Al ₂ O ₃ in the first catalyst provided by the application has strong acidity, and it can further improve the acidity of the first catalyst through the addition of auxiliary agent A, so as to combine with the organic acid added by the organic acid addition device. Acid coordination means that the first hydrogenation reactor can react at a lower hydrogenation temperature;

(4) This application improves the acidity of the reaction system of the first hydrogenation reaction by mixing the raw material containing α,α-dimethylbenzyl alcohol with an organic acid, so that the first hydrogenation reaction can be carried out at a lower temperature, not only The unit consumption of cumene is reduced, and the problem of increased by-products caused by temperature rise is also avoided.

Description of drawings

Fig. 1 is a schematic diagram of a device for producing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol provided by the present application.

Among them: 1, the first hydrogenation reactor; 11, the flash separator; 2, the second hydrogenation reactor; 3, the weight removal device.

Detailed ways

The technical solutions of the present application will be further described below through specific implementation methods. It should be clear to those skilled in the art that the embodiments are only for helping to understand the present application, and should not be regarded as a specific limitation on the present application.

In order to facilitate the description of the technical solution provided by this application, the specific implementation of this application is carried out in the following α,α-dimethylbenzyl alcohol hydrogenolysis device for producing cumene. The structural schematic diagram of the device is shown in Figure 1, including The first hydrogenation reactor 1, the flash separator 11, the second hydrogenation reactor 2 and the weight removal device 3 connected in sequence;

The raw material inlet of the first hydrogenation reactor 1 is provided with an organic acid addition device;

The reactant outlet of the first hydrogenation reactor 1 is provided with a flash separator 11 , and the liquid phase product obtained by the flash separator 11 flows into the second hydrogenation reactor 2 .

The heavy component outlet of the deweighting device 3 is connected with the feed inlet of the second hydrogenation reactor 2 .

The α,α-dimethylbenzyl alcohol undergoes the first hydrogenation reaction in the first hydrogenation reactor 1 , and the second hydrogenation reaction in the second hydrogenation reactor 2 . The product of the first hydrogenation reaction is separated from moisture and organic acid in the flash separator 11 . The second hydrogenated product is subjected to weight removal treatment in the weight removal device 3 to obtain the heavy component containing bibenzyl and the light component cumene.

By arranging an organic acid addition device at the raw material inlet of the first hydrogenation reactor 1, the acidity of the reaction system in the first hydrogenation reactor 1 is improved, thereby reducing the temperature required for the first hydrogenation reaction, not only reducing the The unit consumption of propylbenzene can also reduce the generation of by-product benzene ring hydrogenation products. By connecting the heavy component outlet with the feed port of the second hydrogenation reactor 2, the recovery of p-bibenzyl is realized, and bibenzyl is converted into cumene by the second hydrogenation reaction, reducing the isopropyl benzene caused by the generation of by-products. Propylene consumption.

The preparation method of the first catalyst Pd-A/SiO ₂ -Al ₂ O ₃ catalyst used in the first hydrogenation reactor 1 comprises the following steps:

(a) Mix with aluminum isopropoxide, ethyl silicate and absolute ethanol, heat up to 50°C, then add additive A for hydrolysis, add ammonia water dropwise during the hydrolysis to control the pH to 9; use ultrasonic treatment during the hydrolysis , the hydrolysis temperature is 50°C, and the time is 1h; after the hydrolysis, aging at 60°C for 3h is carried out to obtain the aged slurry;

(b) The aging slurry obtained in step (a) is filtered, dried and roasted to obtain a carrier containing auxiliary agent A;

(c) Under the condition of reflux, the carrier containing auxiliary agent A obtained in step (b) was immersed in a chloroplatinic acid solution for 3 hours at 70° C., and dried and calcined to obtain the first catalyst.

The preparation method of the second catalyst Pd/C catalyst used in the second hydrogenation catalyst 2 comprises the steps:

(1) mixing active carbon and nitric acid with a concentration of 15wt%, washing and drying at 70° C. under reflux for 3 h to obtain a modified carrier; the end point of the washing is to make the washing solution neutral;

(II) Under the condition of reflux, the modified carrier obtained in step (I) was immersed in chloroplatinic acid solution at 70° C. for 3 hours, and dried and calcined to obtain the second catalyst.

Example 1

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, the method comprising the following steps:

(1) The raw material containing α,α-dimethylbenzyl alcohol is mixed with organic acid and hydrogen, and the first hydrogenation reaction is carried out by using the first catalyst, and the water and organic acid are separated by flash evaporation to obtain the first hydrogenation product; the organic The acid is p-toluenesulfonic acid; the added amount of the organic acid is 0.1wt% of the raw material containing α,α-dimethylbenzyl alcohol; the gauge pressure of the first hydrogenation reaction is 2MPa, the temperature is 130°C, and the liquid The hourly space velocity is 2h ^-1 , the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is 200:1;

(2) The first hydrogenation product obtained in step (1) is mixed with hydrogen, and the second hydrogenation reaction is carried out by using the second catalyst, and the second hydrogenation product is deheavy-treated to obtain the cumene product; the second hydrogenation The gauge pressure of the reaction is 2MPa, the temperature is 160°C, and the liquid hourly space velocity is 2h ^-1 ;

Step (2) said deweighting treatment gained light component is cumene product, gained heavy component returns and mixes with the first hydrogenation product, then carries out the second hydrogenation reaction; Described heavy component mixes with the first hydrogenation product In the obtained mixture, the mass percent of bibenzyl is 1 wt%.

The first catalyst is Pd-A/SiO ₂ -Al ₂ O ₃ , the auxiliary agent A is CeO ₂ , the mass percentage of Pd is 1 wt% based on the mass percentage of the first catalyst as 100%, and the A The mass percent content of the SiO 2 -Al ₂ O ₃ carrier is 2.5wt%, and the mass percent content of the carrier SiO ₂ -Al 2 O 3 is 96.5 wt%; the SiO ₂ in the carrier SiO ₂ -Al ₂ O ₃ is 50wt% of the total weight of the carrier.

The second catalyst is a Pd/C catalyst, based on 100% by mass of the second catalyst, the mass percentage of Pd is 1 wt%, and the mass percentage of carrier C is 99 wt%.

The raw materials containing α,α-dimethylbenzyl alcohol in step (1) include: 24wt% α,α-dimethylbenzyl alcohol, ≤0.05wt% propylene oxide, ≤0.3wt% cumyl Hydrogen peroxide, phenol≤0.2wt%, balance is cumene.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤20ppm, the bibenzyl production capacity≤100ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 2

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, the method comprising the following steps:

(1) The raw material containing α,α-dimethylbenzyl alcohol is mixed with organic acid and hydrogen, and the first hydrogenation reaction is carried out by using the first catalyst, and the water and organic acid are separated by flash evaporation to obtain the first hydrogenation product; the organic The acid is p-toluenesulfonic acid; the added amount of the organic acid is 0.05wt% of the raw material containing α,α-dimethylbenzyl alcohol; the gauge pressure of the first hydrogenation reaction is 2MPa, the temperature is 135°C, and the liquid The hourly space velocity is 1.5h ^-1 , the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is 150:1;

(2) The first hydrogenation product obtained in step (1) is mixed with hydrogen, and the second hydrogenation reaction is carried out by using the second catalyst, and the second hydrogenation product is deheavy-treated to obtain the cumene product; the second hydrogenation The gauge pressure of the reaction is 2MPa, the temperature is 165°C, and the liquid hourly space velocity is 1.5h ^-1 ;

Step (2) said deweighting treatment gained light component is cumene product, gained heavy component returns and mixes with the first hydrogenation product, then carries out the second hydrogenation reaction; Described heavy component mixes with the first hydrogenation product In the obtained mixture, the mass percentage of bibenzyl is 0.5wt%.

The first catalyst is the same as the Pd-A/SiO ₂ -Al ₂ O ₃ catalyst provided in Example 1; the second catalyst is the same as the Pd/C catalyst provided in Example 1.

The composition of the α,α-dimethylbenzyl alcohol-containing raw material in step (1) is the same as that in Example 1.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤50ppm, the bibenzyl production capacity≤150ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 3

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, the method comprising the following steps:

(1) The raw material containing α,α-dimethylbenzyl alcohol is mixed with organic acid and hydrogen, and the first hydrogenation reaction is carried out by using the first catalyst, and the water and organic acid are separated by flash evaporation to obtain the first hydrogenation product; the organic The acid is p-toluenesulfonic acid; the added amount of the organic acid is 0.15wt% of the raw material containing α,α-dimethylbenzyl alcohol; the gauge pressure of the first hydrogenation reaction is 2.5MPa, and the temperature is 125°C. The liquid hourly space velocity is 2.5h ^-1 , and the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is 250:1;

(2) The first hydrogenation product obtained in step (1) is mixed with hydrogen, and the second hydrogenation reaction is carried out by using the second catalyst, and the second hydrogenation product is deheavy-treated to obtain the cumene product; the second hydrogenation The gauge pressure of the reaction is 2.5MPa, the temperature is 155°C, and the liquid hourly space velocity is 2.5h ^-1 ;

Step (2) said deweighting treatment gained light component is cumene product, gained heavy component returns and mixes with the first hydrogenation product, then carries out the second hydrogenation reaction; Described heavy component mixes with the first hydrogenation product In the obtained mixture, the mass percentage of bibenzyl is 2wt%.

The first catalyst is the same as the Pd-A/SiO ₂ -Al ₂ O ₃ catalyst provided in Example 1; the second catalyst is the same as the Pd/C catalyst provided in Example 1.

The composition of the α,α-dimethylbenzyl alcohol-containing raw material in step (1) is the same as that in Example 1.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤60ppm, the bibenzyl production capacity≤120ppm, and the purity of cumene≥99.9%wt%. And in the present embodiment α, the transformation rate of α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 4

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, the method comprising the following steps:

(1) The raw material containing α,α-dimethylbenzyl alcohol is mixed with organic acid and hydrogen, and the first hydrogenation reaction is carried out by using the first catalyst, and the water and organic acid are separated by flash evaporation to obtain the first hydrogenation product; the organic The acid is p-toluenesulfonic acid; the added amount of the organic acid is 0.01wt% of the raw material containing α,α-dimethylbenzyl alcohol; the gauge pressure of the first hydrogenation reaction is 1.5MPa, and the temperature is 140°C. The liquid hourly space velocity is 1h ^-1 , and the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is 100:1;

(2) The first hydrogenation product obtained in step (1) is mixed with hydrogen, and the second hydrogenation reaction is carried out by using the second catalyst, and the second hydrogenation product is deheavy-treated to obtain the cumene product; the second hydrogenation The gauge pressure of the reaction is 1.5MPa, the temperature is 170°C, and the liquid hourly space velocity is 1h ^-1 ;

Step (2) said deweighting treatment gained light component is cumene product, gained heavy component returns and mixes with the first hydrogenation product, then carries out the second hydrogenation reaction; Described heavy component mixes with the first hydrogenation product In the obtained mixture, the mass percentage of bibenzyl is 0.01wt%.

The first catalyst is the same as the Pd-A/SiO ₂ -Al ₂ O ₃ catalyst provided in Example 1; the second catalyst is the same as the Pd/C catalyst provided in Example 1.

The composition of the α,α-dimethylbenzyl alcohol-containing raw material in step (1) is the same as that in Example 1.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤200ppm, the bibenzyl production capacity≤400ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 5

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, the method comprising the following steps:

(1) The raw material containing α,α-dimethylbenzyl alcohol is mixed with organic acid and hydrogen, and the first hydrogenation reaction is carried out by using the first catalyst, and the water and organic acid are separated by flash evaporation to obtain the first hydrogenation product; the organic The acid is p-toluenesulfonic acid; the added amount of the organic acid is 0.2wt% of the raw material containing α,α-dimethylbenzyl alcohol; the gauge pressure of the first hydrogenation reaction is 3MPa, the temperature is 120°C, and the liquid The hourly space velocity is 3h ^-1 , the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is 300:1;

(2) The first hydrogenation product obtained in step (1) is mixed with hydrogen, and the second hydrogenation reaction is carried out by using the second catalyst, and the second hydrogenation product is deheavy-treated to obtain the cumene product; the second hydrogenation The gauge pressure of the reaction is 3MPa, the temperature is 150°C, and the liquid hourly space velocity is 3h ^-1 ;

Step (2) said deweighting treatment gained light component is cumene product, gained heavy component returns and mixes with the first hydrogenation product, then carries out the second hydrogenation reaction; Described heavy component mixes with the first hydrogenation product In the obtained mixture, the mass percentage of bibenzyl is 3wt%.

The first catalyst is the same as the Pd-A/SiO ₂ -Al ₂ O ₃ catalyst provided in Example 1; the second catalyst is the same as the Pd/C catalyst provided in Example 1.

The composition of the α,α-dimethylbenzyl alcohol-containing raw material in step (1) is the same as that in Example 1.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤120ppm, the bibenzyl production capacity≤300ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 6

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, and the process parameters of the method are the same as those in Example 1.

The first catalyst used in the first hydrogenation reaction in this example is Pd-A/SiO ₂ -Al ₂ O ₃ , and the auxiliary agent A is B ₂ O ₂ , based on the mass percentage of the first catalyst as 100%, the The mass percentage is 0.05wt%, the mass percentage of A is 2wt%, the mass percentage of the carrier SiO ₂ -Al ₂ O ₃ is 97.95 wt%; the SiO ₂ in the carrier SiO ₂ -Al ₂ O ₃ is the carrier 30% by weight of the total weight.

The second catalyst is a Pd/C catalyst, based on 100% by mass of the second catalyst, the mass percentage of Pd is 0.05 wt%, and the mass percentage of carrier C is 99.95 wt%.

The raw materials containing α,α-dimethylbenzyl alcohol in step (1) include: 18wt% α,α-dimethylbenzyl alcohol, ≤0.05wt% propylene oxide, ≤0.3wt% cumyl Hydrogen peroxide, phenol≤0.2wt%, balance is cumene.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤100ppm, the bibenzyl production capacity≤300ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 7

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, and the process parameters of the method are the same as those in Example 1.

The first catalyst used in the first hydrogenation reaction in this example is Pd-A/SiO ₂ -Al ₂ O ₃ , and the auxiliary agent A is La ₂ O ₃ , based on the mass percentage of the first catalyst as 100%, the The mass percentage is 2wt%, the mass percentage of A is 4wt%, and the mass percentage of the carrier _SiO2 - _Al2O3 is 94wt%; _SiO2 in _{the carrier SiO2-Al2O3 is the total} weight of the carrier 40wt%.

The second catalyst is a Pd/C catalyst, based on 100% by mass of the second catalyst, the mass percentage of Pd is 2 wt%, and the mass percentage of carrier C is 98 wt%.

The raw materials containing α,α-dimethylbenzyl alcohol in step (1) include: 28wt% α,α-dimethylbenzyl alcohol, ≤0.05wt% propylene oxide, ≤0.3wt% cumyl Hydrogen peroxide, phenol≤0.2wt%, balance is cumene.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤40ppm, the bibenzyl production capacity≤100ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 8

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, and the process parameters of the method are the same as those in Example 1.

The first catalyst used in the first hydrogenation reaction in this example is Pd-A/SiO ₂ -Al ₂ O ₃ , the auxiliary agent A is MnO ₂ , and the mass percentage of Pd is content of 0.5wt%, the mass percentage of A is 1wt%, and the mass percentage of the carrier SiO ₂ -Al ₂ O ₃ is 98.5 wt%; the SiO ₂ in the carrier SiO ₂ -Al ₂ O ₃ is the total weight of the carrier 65wt%.

The second catalyst is a Pd/C catalyst, based on 100% by mass of the second catalyst, the mass percentage of Pd is 0.5 wt%, and the mass percentage of carrier C is 99.5 wt%.

The raw materials containing α,α-dimethylbenzyl alcohol in step (1) include: 25wt% α,α-dimethylbenzyl alcohol, ≤0.05wt% propylene oxide, ≤0.3wt% cumyl Hydrogen peroxide, phenol≤0.2wt%, balance is cumene.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤50ppm, the bibenzyl production capacity≤200ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 9

This embodiment provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, except that p-toluenesulfonic acid is replaced by o-toluenesulfonic acid of equal mass, the rest are the same as those in the embodiment 1 is the same.

In the present embodiment step (2) gained cumene product, the content of isopropyl cyclohexane≤50ppm, bibenzyl production capacity≤100ppm, the purity of cumene is ≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 10

This embodiment provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol. The method is the same as in Example 1 except that p-toluenesulfonic acid is replaced by benzenesulfonic acid of equal mass. same.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane≤50ppm, the bibenzyl production capacity≤100ppm, and the purity of cumene≥99.9wt%. And in this example, the conversion rate of α,α-dimethylbenzyl alcohol is more than or equal to 99%.

Example 11

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol. The method is the same as that of Example 1 except that p-toluenesulfonic acid is replaced by oxalic acid of equal mass.

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane ≥ 500ppm, the production of bibenzyl ≥ 2000ppm, and the purity of cumene is < 99wt%. And the conversion rate of α,α-dimethylbenzyl alcohol in this example is ≤96.5%.

Example 12

This example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol. The method is the same as in Example 1 except that p-toluenesulfonic acid is replaced by citric acid of equal mass. .

In the cumene product obtained in step (2) of this embodiment, the content of isopropylcyclohexane ≥ 3500ppm, the bibenzyl production capacity ≥ 300000ppm, and the purity of cumene is < 99wt%. And the conversion rate of α,α-dimethylbenzyl alcohol in this example is ≤98.5%.

Example 13

This example provides a method for producing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, in which the addition of organic acid is 0.008wt% of the raw material containing α,α-dimethylbenzyl alcohol Except, all the other are identical with embodiment 1.

Due to the reduced amount of organic acid added, the efficient conversion of α,α-dimethylbenzyl alcohol could not be achieved under the conditions of 130°C provided in Example 1. In the cumene product obtained in step (2), the content of isopropylcyclohexane<10ppm, the production amount of bibenzyl≤20ppm, and the purity of cumene<92wt%. And the conversion rate of α,α-dimethylbenzyl alcohol in this example is ≤88%.

Comparative example 1

This comparative example provides a method for preparing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol. The method is the same as that of Example 1 except that p-toluenesulfonic acid is replaced by equal mass of sulfuric acid.

Sulfuric acid cannot be recovered by flash separation, and the existence of sulfuric acid affects the smooth progress of the second hydrogenation reaction. The impurity content in the resulting cumene product is higher, and the content of isopropylcyclohexane ≥ 300ppm. ≥10000ppm, the purity of cumene is <98wt%. And the conversion rate of α,α-dimethylbenzyl alcohol in this comparative example is ≤99%.

In summary, the present application increases the acidity of the reaction system in the first hydrogenation reactor by setting an organic acid addition device at the raw material inlet of the first hydrogenation reactor, thereby reducing the temperature required for the first hydrogenation reaction , not only reduces the unit consumption of cumene, but also reduces the generation of by-product benzene ring hydrogenation products; this application realizes the recovery of p-bibenzyl by connecting the heavy component outlet with the feed port of the second hydrogenation reactor Utilize, convert bibenzyl into cumene through the second hydrogenation reaction, reduce the consumption of cumene due to the generation of by-products; SiO ₂ -Al ₂ O ₃ in the first catalyst provided by the application has stronger acidity , it can further improve the acidity of the first catalyst through the addition of the auxiliary agent A, so as to cooperate with the organic acid given by the organic acid adding device, so that the first hydrogenation reactor can react at a lower hydrogenation temperature; the present application By mixing raw materials containing α,α-dimethylbenzyl alcohol with organic acids, the acidity of the reaction system of the first hydrogenation reaction is improved, so that the first hydrogenation reaction can be carried out at a lower temperature, which not only reduces the cumene The unit consumption is low, and the problem of increasing by-products caused by temperature rise is also avoided.

The applicant declares that the above description is only a specific embodiment of the application, but the scope of protection of the application is not limited thereto, and those skilled in the art should understand that any person skilled in the art disclosed in this application Within the technical scope, easily conceivable changes or substitutions all fall within the scope of protection and disclosure of the present application.

Claims (14)

1. A device for producing cumene by hydrogenolysis of α,α-dimethylbenzyl alcohol, which includes a first hydrogenation reactor, a flash separator, a second hydrogenation reactor and a weight removal device connected in sequence;

   Wherein, the raw material inlet of the first hydrogenation reactor is provided with an organic acid addition device; and

   The reactant outlet of the first hydrogenation reactor is provided with a flash separator, wherein the liquid phase product obtained by the flash separator flows into the second hydrogenation reactor.
2. The device according to claim 1, wherein the heavy component outlet of the weight removal device is connected with the feed port of the second hydrogenation reactor.
3. The device according to claim 1 or 2, wherein the first hydrogenation reactor is provided with a first catalyst; the first catalyst is a Pd-A/SiO ₂ -Al ₂ O ₃ catalyst, wherein A is Any one or a combination of at least two of B ₂ O ₃ , La ₂ O ₃ , CeO ₂ or MnO ₂ .
4. The device according to claim 3, wherein, based on the mass percentage of the first catalyst being 100 wt%, the mass percentage of Pd is 0.05-2 wt%;

   Preferably, based on the mass percentage of the first catalyst being 100 wt%, the mass percentage of A is 1-4 wt%;

   Preferably, the mass percentage of the carrier SiO ₂ -Al ₂ O ₃ is 94-98.95 wt% based on 100 wt% of the first catalyst;

   Preferably, SiO ₂ in the carrier SiO ₂ -Al ₂ O ₃ is 30-65 wt% of the total weight of the carrier, and the balance is Al ₂ O ₃ .
5. The device according to any one of claims 1-4, wherein a second catalyst is arranged in the second hydrogenation reactor; the second catalyst is a Pd/C catalyst.
6. The device according to claim 5, wherein, based on 100 wt% of the second catalyst, the mass percentage of Pd is 0.05-2 wt%, and the mass percentage of carrier C is 98-99.95 wt%.
7. A method for preparing cumene by hydrogenolysis of α-dimethylbenzyl alcohol, wherein the method comprises the steps of:

   (1) mixing raw materials containing α,α-dimethylbenzyl alcohol with organic acid and hydrogen, performing a first hydrogenation reaction, flashing and separating water and organic acid, and obtaining a first hydrogenation product;

   (2) The first hydrogenated product obtained in step (1) is mixed with hydrogen to carry out a second hydrogenation reaction, and the obtained second hydrogenated product is subjected to deheavy treatment to obtain a cumene product.
8. The method according to claim 7, wherein the raw material containing α,α-dimethylbenzyl alcohol in step (1) comprises: 18-28wt% α,α-dimethylbenzyl alcohol, ≤0.05wt% Propylene oxide, cumene hydroperoxide ≤0.3wt%, phenol ≤0.2wt%, balance cumene.
9. The method according to claim 7 or 8, wherein the organic acid in step (1) comprises any one or a combination of at least two of benzenesulfonic acid, o-toluenesulfonic acid or p-toluenesulfonic acid.
10. The method according to any one of claims 7 to 9, wherein the amount of the organic acid added in step (1) is 0.01-0.2 wt% of the raw material containing α,α-dimethyl benzyl alcohol.
11. The method according to any one of claims 7 to 10, wherein the catalyst used for the first hydrogenation reaction described in step (1) is the first catalyst;

    Preferably, the gauge pressure of the first hydrogenation reaction in step (1) is 1.5-3MPa, and the temperature is 120-140°C;

    Preferably, the liquid hourly space velocity of the first hydrogenation reaction described in step (1) is 1-3h ^-1 ;

    Preferably, the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol in the first hydrogenation reaction in step (1) is (100-300):1.
12. The method according to any one of claims 7 to 11, wherein the catalyst used for the second hydrogenation reaction described in step (2) is the second catalyst;

    Preferably, the gauge pressure of the second hydrogenation reaction in step (2) is 1.5-3MPa, and the temperature is 150-170°C;

    Preferably, the liquid hourly space velocity of the second hydrogenation reaction in step (2) is 1-3h ^-1 .
13. according to the method described in any one in claim 7 to 12, wherein, step (2) described deweighting treatment gained light component is cumene product, and gained heavy component returns and mixes with the first hydrogenation product, then carries out Second hydrogenation reaction;

    Preferably, in the mixture obtained by mixing the heavy component and the first hydrogenation product, the mass percentage of bibenzyl is 0.01-3wt%, preferably 0.1-1.5wt%.
14. The method according to any one of claims 7 to 13, wherein said method comprises the steps of:

    (1) The raw material containing α,α-dimethylbenzyl alcohol is mixed with organic acid and hydrogen, and the first hydrogenation reaction is carried out by using the first catalyst, and the water and organic acid are separated by flash evaporation to obtain the first hydrogenation product; the organic The amount of acid added is 0.01-0.2wt% of the raw material containing α,α-dimethylbenzyl alcohol; the gauge pressure of the first hydrogenation reaction is 1.5-3MPa, the temperature is 120-140°C, and the liquid hourly space velocity is 1 -3h ^-1 , the volume ratio of hydrogen to α,α-dimethylbenzyl alcohol is (100-300):1;

    (2) The first hydrogenation product obtained in step (1) is mixed with hydrogen, and the second hydrogenation reaction is carried out by using the second catalyst, and the second hydrogenation product is deheavy-treated to obtain the cumene product; the second hydrogenation The gauge pressure of the reaction is 1.5-3MPa, the temperature is 150-170°C, and the liquid hourly space velocity is 1-3h ^-1 .

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