Method for resourceful treatment and recovery of phenolic ketone tar

Abstract

The invention provides a phenolic ketone tar resourceful treatment and recovery method which comprises the following steps: (1) removing light components from phenolic ketone tar, and separating out light fractions to obtain a light component removed material; and (2) adding a cracking catalyst and water into the light component removed material, and carrying out cracking reaction under the conditions of higher than one standard atmospheric pressure and higher than room temperature to obtain a cracking product. The invention further provides a process device for implementing the method.

Description

Technical Field

[0001] The invention belongs to the field of petrochemical industry, and in particular relates to a method for resource processing and recycling of phenol-ketone tar. Background Art

[0002] Phenol is an important chemical raw material, which is widely used in the industrial production of plastics, synthetic fibers, medicines, pesticides and fuel intermediates. After the phenol and acetone production equipment of the isopropylbenzene method separates the products, a large amount of heavy component tar is discharged from the system, which is called phenol ketone tar (phenol tar). The main components of phenol ketone tar can be: 3-10% phenol, 10-25% acetophenone, 8-20% α-methylstyrene dimer, 1-8% 2-cumylphenol, 15-40% 4-cumylphenol, and 15-30% heavy components. Due to differences in production processes, the composition of tar output from each device is quite different.

[0003] In 2023, the production capacity of phenol-ketone equipment in my country will be about 10.23 million tons / a, and about 315,000 tons / a of phenol-ketone tar will be produced. At present, the conventional practice for the treatment of phenol-ketone tar is to incinerate the by-product steam, because the benefits it produces are limited and it causes more serious environmental problems. Some studies have proposed to extract high-value components (phenol and acetophenone) from phenol-ketone tar, and then incinerate the remaining tar, which increases the added value of phenol-ketone tar. However, the total content of phenol and acetophenone in phenol-ketone tar is about 13-35%, and most of the tar still needs to be incinerated, and the environmental improvement effect is not obvious.

[0004] Some studies have proposed that the remaining tar after the recovery of phenol and acetophenone can be cracked at high temperature to crack α-methylstyrene dimer and 2-cumylphenol (ortho-cumylphenol) and 4-cumylphenol (para-cumylphenol) to produce α-methylstyrene. After α-methylstyrene and phenol are hydrogenated, cumene is generated, and cumene is returned to the system as a raw material. However, α-methylstyrene is unstable and easily self-polymerizes or reacts with phenol to generate heavy components with larger molecular weight. Therefore, the total yield of α-methylstyrene and phenol during high-temperature cracking reaction is about 60-70%, and the subsequent high-risk processes such as hydrogenation are involved, which are not economical and safe, and are difficult to apply in practice.

[0005] In order to further increase the added value of phenol-ketone tar, improve the yield of valuable products in tar, reduce the amount of tar incineration, and reduce carbon emissions, it is of great significance to develop a simple, efficient, safe and economical method for resource utilization of phenol-ketone tar. Summary of the invention

[0006] In view of the current problems of low yield of target product, complex process and high production cost when recovering useful products from phenol-ketone tar cracking, in one aspect, the present invention provides a method for resource utilization of phenol-ketone tar by high-pressure catalytic cracking, the method comprising:

[0007] (1) removing light fractions from phenol-ketone tar to separate light fractions and obtain light-removed material;

[0008] (2) adding a cracking catalyst and water to the light-removed material, and carrying out a cracking reaction under conditions higher than a standard atmospheric pressure and higher than room temperature to obtain a cracking product.

[0009] The cracking products of the present invention can be directly separated to obtain cumene and phenol. Compared with the conventional high-temperature cracking method, the present method directly generates cumene and phenol without generating α-methylstyrene. This is because under high temperature and high pressure, α-methylstyrene dimer and 2-cumylphenol and 4-cumylphenol in tar can form cumyl radicals, and the cumyl radicals combine with hydrogen radicals generated by water under high pressure to form cumene. The following chemical formula shows the generation mechanism of cumene under high temperature and high pressure (taking α-methylstyrene dimer and 4-cumylphenol as examples).

[0010]

[0011] In addition, the cracking of α-methylstyrene dimer will produce small amounts of ethylbenzene and butylbenzene (such as sec-butylbenzene).

[0012] The high-pressure catalytic cracking method of phenol-ketone tar reduces the subsequent hydrogenation step. After separation, isopropylbenzene can be directly returned to the phenol-ketone unit for use as raw material. The process flow is simple, the yield of the cracking target product is high, and the economic benefit is good.

[0013] In some embodiments, the method of the present invention further comprises further processing the light fraction to separate phenol and acetophenone.

[0014] In some embodiments, the method of the present invention further comprises further processing the cracking product to separate ethylbenzene, isopropylbenzene and phenol products.

[0015] On the other hand, the present invention also provides a process device for implementing the method of the present invention, which at least includes a device for removing light from phenol-ketone tar and a device for performing cracking reaction.

[0016] In some embodiments, the process unit of the present invention further comprises a device for further processing the separated light fraction.

[0017] In some embodiments, the process device of the present invention further comprises a device for further processing the cracking product.

[0018] The process apparatus of the present invention may also include any other apparatus that can be suitable for implementing the method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1This is a schematic diagram of the process of the phenol-ketone tar resource utilization device in Example 1; the accompanying drawings are described as follows:

[0020] 1-phenol-ketone tar raw material tank, 2-removal light distillation tower, 3-first distillation unit condenser, 4-first distillation unit, 5-phenol receiving tank, 6-second distillation unit condenser, 7-second distillation unit, 8-acetophenone receiving tank, 9-high-pressure cracking reactor, 10-third distillation unit condenser, 11-third distillation unit, 12-ethylbenzene receiving tank, 13-fourth distillation unit condenser, 14-fourth distillation unit, 15-isopropylbenzene receiving tank, 16-fifth distillation unit condenser, 17-fifth distillation unit, 18-phenol receiving tank, 19-heavy oil receiving tank. DETAILED DESCRIPTION

[0021] "Scope" disclosed herein is defined in the form of lower limit and upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a particular range. The scope defined in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a particular parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following scope can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this application, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0022] In this application, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form a new technical solution.

[0023] In this application, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

[0024] In the present application, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0025] In this application, unless otherwise specified, the terms "include" and "comprising" mentioned herein may be open-ended or closed-ended. For example, the terms "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0026] In the description of this article, it should be noted that, unless otherwise specified, "above" and "below" are inclusive of the number itself, and "several" in "one or several" means two or more.

[0027] In the description herein, unless otherwise specified, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0028] Herein, unless otherwise specified, percentage (%) or part refers to percentage by weight or part by weight relative to the composition.

[0029] Herein, if there is no contrary description, the sum of the contents of the various components in the composition is 100%.

[0030] Herein, if there is no contrary description, the sum of the parts of each component in the composition may be 100 parts by weight.

[0031] In this context, unless otherwise specified, "a combination thereof" means a multi-component mixture of the elements described, for example a mixture of two, three, four and up to the maximum possible multi-component mixture.

[0032] If not specifically stated, the terms "a" or "an" used in the present specification means "at least one".

[0033] Herein, unless otherwise stated, all reactions are carried out at normal temperature and pressure.

[0034] One aspect of the present application provides a method for resource processing and recovery of phenol-ketone tar, the method comprising:

[0035] (1) removing light fractions from phenol-ketone tar to separate light fractions and obtain light-removed material;

[0036] (2) adding a cracking catalyst and water to the light-removed material, and carrying out a cracking reaction under conditions higher than a standard atmospheric pressure and higher than room temperature to obtain a cracking product.

[0037] Phenolic tar

[0038] In this article, "phenol-ketone tar", also known as phenol tar, is a heavy component tar produced as a byproduct of the production of phenol and acetone by the cumene method. In the process of producing phenol and acetone by the cumene method, benzene and propylene react under the action of a catalyst to produce cumene, and cumene undergoes an oxidation reaction with oxygen to produce cumene hydroperoxide. Cumene hydroperoxide decomposes under the action of an acid (such as sulfuric acid) to produce phenol and acetone. Phenol and acetone are obtained by separation, and the remaining byproduct is phenol-ketone tar. The components in phenol tar are complex, and due to differences in the process routes and types of catalysts adopted by different manufacturers, the proportions of each component in the phenol tar produced by each manufacturer will vary to a certain extent. The main components of phenol-ketone tar can include α-methylstyrene dimer, 2-cumylphenol, 4-cumylphenol, phenol, acetophenone, heavy oil, etc.

[0039] Take off the light

[0040] In this article, "light removal" refers to the use of the volatility / boiling point difference of a substance to achieve the separation of light components and heavy components. The light removal tower, also known as the light component removal tower, is usually used for light removal. It is a device that uses the volatility / boiling point difference of a substance to remove light components from a mixture. The working principle of the light removal tower is based on the different volatilities of the components in the mixture. In the tower, the mixture is heated and condensed. The light components are enriched at the top of the tower due to their high volatility, while the heavy components are enriched at the bottom of the tower, to obtain light fractions and light-removed materials, respectively. By controlling the temperature and pressure at the top and bottom of the tower, effective separation of light components can be achieved.

[0041] In step (1) of the method of the present invention, the phenol-ketone tar is delightened. The purpose of delightening the phenol-ketone tar is to remove phenol and acetophenone from the phenol-ketone tar. Therefore, the separated light fraction mainly contains phenol and acetophenone. The delightened material after the light fraction is removed contains α-methylstyrene dimer, 2-cumylphenol, 4-cumylphenol, heavy oil, etc. For example, the delightening can be carried out using a negative pressure distillation device, such as a delightening tower, with a theoretical plate number of 2 to 25, preferably 5 to 20, a pressure of 1 to 20 Kpa, preferably 2 to 10 Kpa, and a reflux ratio of 0.1 to 2, preferably 0.5 to 1.5.

[0042] Separation of light fractions

[0043] The separated light fraction can be further processed to separate phenol and acetophenone. The light fraction can pass through at least two distillation separation devices, such as a first distillation device and a second distillation device, for example, wherein the first distillation device has a theoretical plate number of 20 to 120, preferably 30 to 100, a pressure of 50 to 150 KPa, preferably 60 to 130 KPa, and a reflux ratio of 2 to 25, preferably 3 to 20; the second distillation device has a theoretical plate number of 10 to 120, preferably 20 to 80, a pressure of 0.5 to 15 KPa, preferably 1 to 10 KPa, and a reflux ratio of 0.1 to 8, preferably 0.5 to 5.

[0044] Lysis

[0045] As used herein, "cracking" refers to a chemical process in which a higher molecular weight substance is converted into one or more lower molecular weight substances under conditions such as high temperature or a catalyst.

[0046] In step (2) of the method of the present invention, a cracking catalyst and water are added to the light-removed material, and a cracking reaction is carried out at high temperature and high pressure to obtain a cracking product. The cracking targets are mainly α-methylstyrene dimer, 2-cumylphenol and 4-cumylphenol.

[0047] Preferably, the cracking reaction pressure is 1 to 50 MPa, or 1.5 to 15 MPa, or 2 to 10 MPa. For example, the cracking reaction pressure may be 1 MPa, 1.5 MPa, 2.0 MPa, 2.5 MPa, 3.0 MPa, 3.5 MPa, 3.6 MPa, 3.7 MPa, 3.8 MPa, 3.9 MPa, 4.0 MPa, 4.1 MPa, 4.2 MPa, 4.3 MPa, 4.4 MPa, 4.5 MPa, 4.6 MPa, 4.7 MPa, 4.8 MPa, 4.9 MPa, 5.0 MPa, 5.1 MPa, 5.2 MPa, 5.3 MPa, 5.4 MPa, 5.5 MPa, 5.6 MPa, 5.7 MPa, 5.8 MPa, 5.9 MPa, 6.0 MPa, 6.1 MPa, 6.2 MPa, 6.3 MPa, 6.4 MPa, 6.5 MPa, 6.6 MPa, 6.7 MPa, 6.8 MPa, 6.9 MPa, 7.0 MPa, 7.1 MPa, 7.2 MPa, 7.3 MPa, 7.4 MPa, 7.5 MPa, 7.6 MPa, 7.7 MPa, 7.8 MPa, 7.9 MPa, 8.0 MPa, 8.1 MPa, 8. 2Mpa, 5.3Mpa, 5.4Mpa, 5.5Mpa, 6.0Mpa, 6.5Mpa, 7.0Mpa, 7.5Mpa, 8.0Mpa, 8.5Mpa, 9.0Mpa, 9.5Mpa, 1 0Mpa, 11Mpa, 12Mpa, 13Mpa, 14Mpa, 15Mpa, 16Mpa, 17Mpa, 18Mpa, 19Mpa, 20Mpa, 30Mpa, 40Mpa, 50Mpa.

[0048] In this article, "room temperature" is also called general temperature or normal temperature, which is usually defined as a temperature of 25°C.

[0049] The cracking reaction temperature is 200-450° C., or 230-400° C., or 260-350° C. For example, the temperature of the cracking reaction can be 200° C., 210° C., 220° C., 230° C., 240° C., 250° C., 260° C., 270° C., 280° C., 290° C., 300° C., 310° C., 320° C., 330° C., 340° C., 350° C., 360° C., 370° C., 380° C., 390° C., 400° C., 450° C.

[0050] Preferably, the cleavage reaction time is 1 to 25 h, or 2 to 20 h, or 3 to 15 h.

[0051] The cleavage can be carried out in a high pressure reaction device. For example, the high pressure reaction device is selected from a high pressure reactor, a fixed bed reactor, a microchannel reactor, a tubular reactor, etc. The cleavage can be carried out in a high pressure cleavage reactor, such as a high pressure cleavage reactor with a stirring device.

[0052] Preferably, the cleavage reaction is carried out in an atmosphere of a non-reactive gas. Preferably, the cleavage reaction is carried out in an atmosphere selected from nitrogen, argon or helium, for example, the cleavage reaction of the present invention is carried out in a nitrogen atmosphere. In this article, "non-reactive gas" refers to a gas that does not participate in the reaction of the present invention.

[0053] Cracking Catalyst

[0054] In the present invention, a cracking catalyst is added to the cracking reaction. The cracking catalyst can be selected from alkaline catalysts, such as sodium hydroxide, potassium hydroxide, calcium hydroxide and magnesium hydroxide. The cracking catalyst can be selected from solid base catalysts. The cracking catalyst can be selected from acid catalysts, such as organic acids or inorganic acids, such as formic acid, acetic acid, hydrochloric acid, boric acid, phosphoric acid, sulfuric acid, etc. The cracking catalyst can be selected from solid acid catalysts. The cracking catalyst can be selected from oxide catalysts, such as Al2O3, MgO, CaO, Na2O, K2O and SiO2. The cracking catalyst can be selected from salt catalysts, such as sulfates, such as MgSO4, ZnSO4. The cracking catalyst can be loaded on a carrier.

[0055] Preferably, based on the weight of the light material removed, the amount of catalyst used is 0.1 to 5% by weight, or 0.5 to 4% by weight, or 1.0 to 3% by weight. For example, the amount of catalyst used may be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4.0%, 4.1%, 4.2%, 4.3%, 4.4%, 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5. 5wt%, 2.6wt%, 2.7wt%, 2.8wt%, 2.9wt%, 3.0wt%, 3.1wt%, 3.2wt%, 3.3wt%, 3.4wt%, 3.5wt%, 3.6wt%, 3.7wt%, 3.8wt%, 3.9wt%, 4.0wt%, 4.1wt%, 4.2wt%, 4.3wt%, 4.4wt%, 4.5wt%, 4.6wt%, 4.7wt%, 4.8wt%, 4.9wt%, 5.0wt%.

[0056] Adding water

[0057] In the cracking reaction of step (2), water is added. As mentioned above, the role of water is to generate hydrogen free radicals under high pressure. Under high temperature and high pressure, α-methylstyrene dimer and 2-cumylphenol and 4-cumylphenol can all form cumyl free radicals, and the cumyl free radicals combine with hydrogen free radicals to form isopropylbenzene.

[0058] Preferably, based on the weight of the de-lightened material, the amount of water added may be 0.1-5 wt%, or 0.5-4 wt%, or 1.0-3 wt%. Preferably, the amount of water added may be 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1.0 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, 1.7 wt%, 1.8 wt%, 1.9 wt%, 2.0 wt%, 2.1 wt%, 2.2 wt%, 2.3 wt%, 2.4 wt%. , 2.5 weight %, 2.6 weight %, 2.7 weight %, 2.8 weight %, 2.9 weight %, 3.0 weight %, 3.1 weight %, 3.2 weight %, 3.3 weight %, 3.4 weight %, 3.5 weight %, 3.6 weight %, 3.7 weight %, 3.8 weight %, 3.9 weight %, 4.0 weight %, 4.1 weight %, 4.2 weight %, 4.3 weight %, 4.4 weight %, 4.5 weight %, 4.6 weight %, 4.7 weight %, 4.8 weight %, 4.9 weight %, 5.0 weight %.

[0059] Separation of cleavage products

[0060] In the present invention, the cracking product may include cumene, phenol, and ethylbenzene. Optionally, the method of the present invention further comprises separating the cracking product to obtain ethylbenzene, cumene, and phenol products respectively. For example, the cracking product is passed through at least three distillation separation devices to obtain ethylbenzene, cumene, and phenol products respectively. For example, the at least three distillation separation devices include a third distillation device, a fourth distillation device, and a fifth distillation device. For example, the third distillation device has a theoretical plate number of 30 to 80, preferably 50 to 70, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.5 to 10, preferably 1 to 8; the fourth distillation device has a theoretical plate number of 30 to 80, preferably 30 to 50, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.2 to 5, preferably 0.5 to 3; the fifth distillation device has a theoretical plate number of 30 to 80, preferably 30 to 50, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.5 to 10, preferably 0.5 to 3.

[0061] For example, the cracking product is first transferred to the third distillation unit for distillation, and ethylbenzene is produced from the top of the third distillation unit; the bottom material of the third distillation tower enters the fourth distillation unit, and isopropylbenzene is produced from the top of the tower; the bottom material of the fourth distillation tower enters the fifth distillation unit, and phenol is produced from the top of the tower, and heavy oil is obtained in the bottom of the tower.

[0062] Another aspect of the present application provides a process device for implementing the method according to any one of the preceding claims, comprising at least a device for removing light fractions from phenol-ketone tar and a device for performing cracking reactions. Optionally, the process device of the present invention may also include a device for separating light fractions and / or a device for separating cracking products.

[0063] Lightweight device

[0064] In the present invention, the device for removing light components from phenol-ketone tar can be a distillation device, such as a negative pressure distillation device. The device for removing light components from phenol-ketone tar can be a light component removal tower. A light component removal tower, also known as a light component removal tower, is a device that utilizes the volatility difference of a substance to remove light components from a mixture. The working principle of the light component removal tower is based on the different volatilities of the components in the mixture. In the tower, the mixture is heated and condensed, and the light components are enriched at the top of the tower due to their high volatility, while the heavy components are enriched at the bottom of the tower, to obtain light fractions and light-removed materials, respectively. By controlling the temperature and pressure at the top and bottom of the tower, effective separation of light components can be achieved.

[0065] In step (1) of the method of the present invention, the phenol-ketone tar is subjected to light removal. The purpose of light removal of the phenol-ketone tar is to remove phenol and acetophenone from the phenol-ketone tar. Therefore, the separated light fraction mainly contains phenol and acetophenone. The light-removed material after the light fraction is removed contains α-methylstyrene dimer, 2-cumylphenol, 4-cumylphenol, heavy oil, etc. For example, the light removal can be carried out using a negative pressure distillation device, such as a light removal tower, the theoretical number of plates of the negative pressure distillation device is 2 to 25, preferably 5 to 20, the pressure is 1 to 20 Kpa, preferably 2 to 10 Kpa, and the reflux ratio is 0.1 to 2, preferably 0.5 to 1.5.

[0066] Light fraction separation unit

[0067] The separated light fraction can be further processed to separate phenol and acetophenone. The light fraction can pass through at least two distillation separation devices, such as a first distillation device and a second distillation device, for example, wherein the first distillation device has a theoretical plate number of 20 to 120, preferably 30 to 100, a pressure of 50 to 150 KPa, preferably 60 to 130 KPa, and a reflux ratio of 2 to 25, preferably 3 to 20; the second distillation device has a theoretical plate number of 10 to 120, preferably 20 to 80, a pressure of 0.5 to 15 KPa, preferably 1 to 10 KPa, and a reflux ratio of 0.1 to 8, preferably 0.5 to 5.

[0068] For example, the light fraction first enters the first distillation device, and high-content phenol is extracted from the top of the first distillation device. The bottom material enters the second distillation device, and high-content acetophenone is extracted from the top of the second distillation device.

[0069] Cracking unit

[0070] In this article, "cracking" refers to a chemical process in which a higher molecular weight substance is converted into one or more lower molecular weight substances under conditions such as high temperature or a catalyst. The cracking reaction can be carried out in a high pressure reaction device. For example, the high pressure reaction device is selected from a high pressure reaction kettle, a fixed bed reactor, a microchannel reactor, a tubular reactor, etc. The cracking can be carried out in a high pressure cracking reactor, such as a high pressure cracking reactor with a stirring device.

[0071] Preferably, the cracking reaction pressure is 1 to 50 MPa, or 1.5 to 15 MPa, or 2 to 10 MPa. For example, the cracking reaction pressure may be 1 MPa, 1.5 MPa, 2.0 MPa, 2.5 MPa, 3.0 MPa, 3.5 MPa, 3.6 MPa, 3.7 MPa, 3.8 MPa, 3.9 MPa, 4.0 MPa, 4.1 MPa, 4.2 MPa, 4.3 MPa, 4.4 MPa, 4.5 MPa, 4.6 MPa, 4.7 MPa, 4.8 MPa, 4.9 MPa, 5.0 MPa, 5.1 MPa, 5.2 MPa, 5.3 MPa, 5.4 MPa, 5.5 MPa, 5.6 MPa, 5.7 MPa, 5.8 MPa, 5.9 MPa, 6.0 MPa, 6.1 MPa, 6.2 MPa, 6.3 MPa, 6.4 MPa, 6.5 MPa, 6.6 MPa, 6.7 MPa, 6.8 MPa, 6.9 MPa, 7.0 MPa, 7.1 MPa, 7.2 MPa, 7.3 MPa, 7.4 MPa, 7.5 MPa, 7.6 MPa, 7.7 MPa, 7.8 MPa, 7.9 MPa, 8.0 MPa, 8.1 MPa, 8. 2Mpa, 5.3Mpa, 5.4Mpa, 5.5Mpa, 6.0Mpa, 6.5Mpa, 7.0Mpa, 7.5Mpa, 8.0Mpa, 8.5Mpa, 9.0Mpa, 9.5Mpa, 1 0Mpa, 11Mpa, 12Mpa, 13Mpa, 14Mpa, 15Mpa, 16Mpa, 17Mpa, 18Mpa, 19Mpa, 20Mpa, 30Mpa, 40Mpa, 50Mpa.

[0072] The cracking reaction temperature is 200-450° C., or 230-400° C., or 260-350° C. For example, the temperature of the cracking reaction can be 200° C., 210° C., 220° C., 230° C., 240° C., 250° C., 260° C., 270° C., 280° C., 290° C., 300° C., 310° C., 320° C., 330° C., 340° C., 350° C., 360° C., 370° C., 380° C., 390° C., 400° C., 450° C.

[0073] Preferably, the cleavage reaction time is 1 to 25 h, or 2 to 20 h, or 3 to 15 h.

[0074] Device for separating cleavage products

[0075] In the present invention, the cracking product may include cumene, phenol, and ethylbenzene. Optionally, the method of the present invention further comprises separating the cracking product to obtain ethylbenzene, cumene, and phenol products respectively. For example, the cracking product is passed through at least three distillation separation devices to obtain ethylbenzene, cumene, and phenol products respectively. For example, the at least three distillation separation devices include a third distillation device, a fourth distillation device, and a fifth distillation device. For example, the third distillation device has a theoretical plate number of 30 to 80, preferably 50 to 70, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.5 to 10, preferably 1 to 8; the fourth distillation device has a theoretical plate number of 30 to 80, preferably 30 to 50, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.2 to 5, preferably 0.5 to 3; the fifth distillation device has a theoretical plate number of 30 to 80, preferably 30 to 50, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.5 to 10, preferably 0.5 to 3.

[0076] For example, the cracking product is first transferred to the third distillation unit for distillation, and ethylbenzene is produced from the top of the third distillation unit; the bottom material of the third distillation tower enters the fourth distillation unit, and isopropylbenzene is produced from the top of the tower; the bottom material of the fourth distillation tower enters the fifth distillation unit, and phenol is produced from the top of the tower, and heavy oil is obtained in the bottom of the tower.

[0077] Example

[0078] In order to make the technical solution and effect of the present invention clearer, the technical solution of the present invention will be further described in conjunction with some specific embodiments. The described embodiments are intended to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention.

[0079] In the examples, unless otherwise specified, percentages (%) or parts refer to percentages by weight or parts by weight.

[0080] The phenol-ketone tar described in the embodiments of the present invention and the comparative examples is produced from the phenol-ketone device of Jiangsu Ruiheng New Materials Co., Ltd., and the composition of the phenol-ketone tar is as follows: phenol content 7.1%, acetophenone content 20.9%, α-methylstyrene dimer content 8.5%, 2-cumylphenol content 4.0%, 4-cumylphenol content 21.1%, and the rest are heavy components.

[0081] For the purpose of simplicity, since the cracking raw materials cumylphenol and α-methylstyrene dimer molecules both have two benzene rings, and the target products phenol and isopropylbenzene molecules both have one benzene ring, the conversion rate and yield are calculated based on the combined molar amount of benzene rings.

[0082] Example 1

[0083] The phenol-ketone tar is put into a light fraction removal distillation tower with 10 plates, a pressure of 5 Kpa, a reflux ratio of 1, a top temperature of 113°C, and a bottom temperature of 200°C to obtain a top effluent (light fraction) and light fraction removal material (heavy fraction).

[0084] The weight of the top effluent accounts for 28.1% of the weight of the feed tar, of which the phenol content is 25.5% and the acetophenone content is 71.6%.

[0085] The top effluent is further separated by two distillation devices. The first distillation device has a theoretical plate number of 70, a pressure of 80 Kpa, a reflux ratio of 10, a top temperature of 172°C, a bottom temperature of 194°C, and a phenol content of 96.5% is extracted from the top of the tower. The bottom material enters the second distillation device. The second distillation device has a theoretical plate number of 70, a pressure of 5 Kpa, a reflux ratio of 1.5, a top temperature of 109°C, a bottom temperature of 122°C, and a 99.9% acetophenone content is extracted from the top of the tower.

[0086] The de-light material contained 11.3% α-methylstyrene dimer, 5.5% 2-cumylphenol, 29.3% 4-cumylphenol, and the rest were heavy components.

[0087] The light-removed material was added to a high-pressure cracking reactor (Yantai Songling Chemical Equipment Co., Ltd., model: KCFD1-10), and then 1.5% by weight of phosphoric acid and 2% by weight of water based on the weight of the light-removed material were added. The mixture was stirred under a nitrogen pressure of 1 MPa, heated to 320°C and the pressure gradually increased to about 4.5 MPa, and then kept stable for 6 hours. After cooling, the composition of the cracking products was separated by sampling (GC internal standard analysis method): ethylbenzene content 3.8%, isopropylbenzene content 30.8%, phenol content 15.3%, heavy oil content 47.8%, α-methylstyrene dimer and 2-cumylphenol, 4-cumylphenol conversion rate 100%, and the total molar yield of isopropylbenzene and phenol in the cracking reaction was 99.5%.

[0088] The cracking products are transferred to the third distillation device for distillation. The third distillation device has a theoretical plate number of 50, a pressure of 10 Kpa, a reflux ratio of 2, a tower top temperature of 57°C, a tower bottom temperature of 95°C, and ethylbenzene with a content of 95% is produced from the tower top; the kettle material of the third distillation tower enters the fourth distillation device, with a theoretical plate number of 50, a pressure of 10 Kpa, a reflux ratio of 2, a tower top temperature of 80°C, a tower bottom temperature of 120°C, and isopropylbenzene with a content of 99.9% is produced from the tower top. The kettle material of the fourth distillation tower enters the fifth distillation device, with a theoretical plate number of 50, a pressure of 10 Kpa, a reflux ratio of 3, a tower top temperature of 110°C, a tower bottom temperature of 132°C, and phenol with a content of 99.3% is produced from the tower top. The heavy oil accounts for 31.2% of the weight of the feed tar.

[0089] Example 2

[0090] Except that solid NaOH is used as the cracking catalyst instead of phosphoric acid, the other conditions are the same as those in Example 1, and the cracking product composition is as follows: ethylbenzene content 4.6%, isopropylbenzene content 28.6%, phenol content 14.2%, α-methylstyrene dimer content 0.1%, 4-cumylphenol content 0.1%, heavy oil content 52.2%, conversion rate of α-methylstyrene dimer and 2-cumylphenol, 4-cumylphenol is 99.6%, and the total molar yield of isopropylbenzene and phenol in the cracking reaction is 92.1%.

[0091] Example 3

[0092] Except that acetic acid is used as the cracking catalyst instead of phosphoric acid, the other conditions are the same as those in Example 1, and the cracking product composition is as follows: ethylbenzene content 5.5%, isopropylbenzene content 30.1%, phenol content 15.3%, α-methylstyrene dimer content 0.1%, 4-cumylphenol content 0.2%, heavy oil content 48.1%, α-methylstyrene dimer and 2-cumylphenol, 4-cumylphenol conversion rate is 99.3%, and the total molar yield of isopropylbenzene and phenol in the cracking reaction is 99.1%.

[0093] Comparative Example 1

[0094] Except that no catalyst is added to the cracking reaction, the other conditions are consistent with those of Example 1, and the cracking product composition: ethylbenzene content 1.1%, isopropylbenzene content 7.1%, α-methylstyrene content 1.1%, phenol content 5.4%, α-methylstyrene dimer content 7.3%, 2-cumylphenol content 3.2%, 4-cumylphenol content 18.8%, heavy oil content 55.3%, α-methylstyrene dimer and 2-cumylphenol, 4-cumylphenol conversion rate 36.4%, cracking reaction isopropylbenzene, phenol total molar yield 27.9%.

[0095] Comparative Example 2

[0096] Except that no water is added to the cracking reaction, the other conditions are consistent with those of Example 1, and the cracking product composition is as follows: ethylbenzene content 4.4%, isopropylbenzene content 11.7%, α-methylstyrene content 17.2%, phenol content 15.1%, α-methylstyrene dimer content 0.2%, 2-cumylphenol content 0.2%, 4-cumylphenol content 0.3%, heavy oil content 50.2%, α-methylstyrene dimer and 2-cumylphenol, 4-cumylphenol conversion rate 98.5%, the cracking reaction generates a large amount of α-methylstyrene, isopropylbenzene, phenol total molar yield 60.5%.

[0097] Comparative Example 3

[0098] Except that atmospheric pressure cracking is used for cracking, the other conditions are consistent with those of Example 1. A reactor with a light component extraction device is used for atmospheric pressure cracking. The temperature is raised to 320° C. with stirring and kept warm for 6 hours. The amount of light component recovered by cracking accounts for 47.5% of the amount of tar fed. The light component composition includes 4.7% ethylbenzene content, 13.6% isopropylbenzene content, 38.2% α-methylstyrene content, and 34.1% phenol content. The kettle feed is a heavy component. The conversion rate of α-methylstyrene dimer and 2-cumylphenol and 4-cumylphenol is 92.2%. The cracking reaction generates a large amount of α-methylstyrene, and the total molar yield of isopropylbenzene and phenol is 64.8%.

[0099] Comparative Example 4

[0100] Except that the cracking uses normal pressure cracking, no water is added for reaction, and the holding time is extended, the other conditions are consistent with Example 1. The normal pressure cracking adopts a reactor with a light component extraction device, and the temperature is raised to 320° C. with stirring and kept warm for 8 hours. The cracking light component recovery accounts for 59.1% of the feeding tar amount, and the light component composition includes: ethylbenzene content 10.5%, isopropylbenzene content 15.2%, α-methylstyrene content 33.5%, phenol content 25.0%, the kettle feed is a heavy component, the conversion rate of α-methylstyrene dimer and 2-cumylphenol and 4-cumylphenol is 96.5%, and the cracking reaction generates a large amount of α-methylstyrene, and the total molar yield of isopropylbenzene and phenol is 51.5%.

[0101] Cracking pressure

[0102] Based on Example 1, the results produced by using different cracking pressures were compared through further Examples 4-5 and Comparative Example 3. Except for the different cracking pressures, other conditions of Examples 4-5 and Comparative Example 3 were the same as those of Example 1.

[0103] The results are summarized in Table 1 below:

[0104] Table 1

[0105]

[0106]

[0107] As can be seen from the above table, if the pressure is too low, it is not conducive to the generation of hydrogen free radicals from water, resulting in a low combined molar yield of isopropylbenzene and phenol; if the pressure is too high, the side reactions increase, and the cracking products react with each other to regenerate cumylphenol, resulting in a decrease in the reaction conversion rate and yield.

[0108] Amount of water added

[0109] Based on Example 1, the results produced by using different water addition amounts were compared through further Examples 5-7 and Comparative Example 2. Except for the different water addition amounts, other conditions of Examples 5-7 and Comparative Example 2 were the same as those of Example 1.

[0110] The results are summarized in Table 2 below:

[0111] Table 2

[0112]

[0113] As can be seen from the table above, if no water is added, the yield is significantly reduced. If the amount of water is too low, the hydrogen free radicals formed are small, which leads to the cracking to generate α-methylstyrene, but is not conducive to the formation of isopropylbenzene; adding too much water will lead to a decrease in the conversion rate of the cracking reaction.

[0114] catalyst

[0115] Based on Example 1, the results produced by using the catalysts were compared through further Examples 2-3, 8-13 and Comparative Example 1. Except for the different catalysts, other conditions of Examples 2-3, 8-13 and Comparative Example 1 were the same as those of Example 1.

[0116] The results are summarized in Table 3 below:

[0117] Table 3

[0118]

[0119] As can be seen from the table above, the yields obtained by using acid catalysts such as phosphoric acid, acetic acid, sulfuric acid, and zirconium sulfate are high. The conversion rate obtained by using solid NaOH is also good, but the yield is slightly lower than that of the acid catalyst.

[0120] In summary, through the high-pressure cracking method of the present invention, water and a cracking catalyst are added to carry out resource processing of phenol-ketone tar, isopropylbenzene and phenol can be obtained, α-methylstyrene is not generated, the subsequent hydrogenation step is avoided, and it has a high conversion rate and selectivity, and the amount of heavy oil after cracking is greatly reduced.

[0121] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A method for recycling phenol-ketone tar, comprising: (1) removing light fractions from phenol-ketone tar to separate light fractions and obtain light-removed material; (2) adding a cracking catalyst and water to the light-removed material, and carrying out a cracking reaction under conditions higher than a standard atmospheric pressure and higher than room temperature to obtain a cracking product.

2. The method according to any one of the preceding claims, wherein the phenol-ketone tar is a heavy component tar produced as a byproduct of the production of phenol and acetone by the cumene process; For example, the phenol-ketone tar contains phenol, acetophenone, α-methylstyrene dimer, 2-cumylphenol, 4-cumylphenol, and heavy oil.

3. The method according to any one of the preceding claims, wherein the light fraction of phenol-ketone tar is to remove phenol and acetophenone from the phenol-ketone tar, the light fraction contains phenol and acetophenone, and the light fraction contains α-methylstyrene dimer, 2-cumylphenol, 4-cumylphenol and heavy oil; For example, the light removal adopts a negative pressure distillation device; For example, the number of theoretical plates of the negative pressure distillation device is 2 to 25, preferably 5 to 20, the pressure is 1 to 20 KPa, preferably 2 to 10 KPa, and the reflux ratio is 0.1 to 2, preferably 0.5 to 1.

5.

4. The method according to any one of the preceding claims, wherein the light fraction comprises phenol and acetophenone, and the light fraction is separated to obtain phenol and acetophenone respectively; For example, the light fraction is passed through at least two distillation separation devices to obtain phenol and acetophenone respectively; For example, the at least two distillation separation devices include a first distillation device and a second distillation device, for example, the first distillation device has a theoretical plate number of 20 to 120, preferably 30 to 100, a pressure of 50 to 150 Kpa, preferably 60 to 130 Kpa, and a reflux ratio of 2 to 25, preferably 3 to 20; the second distillation device has a theoretical plate number of 10 to 120, preferably 20 to 80, a pressure of 0.5 to 15 Kpa, preferably 1 to 10 Kpa, and a reflux ratio of 0.1 to 8, preferably 0.5 to 5.

5. The method of claim 1, wherein Preferably, the cracking reaction pressure is 1 to 50 MPa, or 1.5 to 15 MPa, or 2 to 10 MPa; and / or Preferably, the cracking reaction temperature is 200-450°C, or 230-400°C, or 260-350°C; and / or Preferably, the cleavage reaction time is 1 to 25 h, or 2 to 20 h, or 3 to 15 h.

6. The method according to any one of the preceding claims, wherein the pyrolysis is carried out using a high pressure reaction device; For example, the high-pressure reaction device is selected from a high-pressure reactor, a fixed bed reactor, a microchannel reactor, and a tubular reactor.

7. The method according to any one of the preceding claims, wherein the cracking catalyst is selected from a base catalyst and an acid catalyst; Preferably, the cracking catalyst is selected from at least one of sodium hydroxide, potassium hydroxide, calcium hydroxide, formic acid, acetic acid, hydrochloric acid, boric acid, phosphoric acid, sulfuric acid, solid acid, and solid base; Preferably, based on the weight of the light material removed, the amount of the catalyst used is 0.1 to 5 weight %, or 0.5 to 4 weight %, or 1 to 3 weight %.

8. A method as claimed in any one of the preceding claims, wherein Based on the weight of the light-removed material, the amount of water added in step (2) is 0.1 to 5% by weight, or 0.5 to 4% by weight, or 1 to 3% by weight.

9. The method according to any one of the preceding claims, wherein the pyrolysis products comprise cumene, phenol, and ethylbenzene, and the method further comprises separating the pyrolysis products to obtain ethylbenzene, cumene, and phenol products respectively; Preferably, the cracking product passes through at least three distillation separation devices to obtain ethylbenzene, cumene and phenol products respectively; For example, the at least three distillation separation devices include a third distillation device, a fourth distillation device and a fifth distillation device; Preferably, the third distillation device has a theoretical plate number of 30 to 80, preferably 50 to 70, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.5 to 10, preferably 1 to 8; the fourth distillation device has a theoretical plate number of 30 to 80, preferably 30 to 50, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.2 to 5, preferably 0.5 to 3; the fifth distillation device has a theoretical plate number of 30 to 80, preferably 30 to 50, a pressure of 3 to 25 Kpa, preferably 5 to 20 Kpa, and a reflux ratio of 0.5 to 10, preferably 0.5 to 3.

10. A process device for implementing the method according to any one of the preceding claims, comprising at least a device for removing lightness from phenol-ketone tar and a device for performing cracking reaction.

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