Process for preparation of 1, 1, 2, 3-tetrachloropropene from D-D blends

Abstract

The present application relates to a method for preparing tetrachloropropane and 1, 2-dichloropropane from a D-D mixture, the method comprising the steps of: a) feeding a first feed into a first reaction device via an inlet of the first reaction device, the first feed comprising a D-D mixture and chlorine gas, the first reaction device being a microchannel reactor, the first reaction device being a reactor having a plurality of microchannels; and the D-D mixture comprises 1, 2-dichloropropane, 1, 3-dichloropropene and 2, 3-dichloropropene, and the component A comprises 1, 2-dichloropropane, 1, 3-dichloropropene and 2, 3-dichloropropene. B) reacting the first feed in the first reaction device to form a first reaction mixture, the first reaction mixture comprising 1, 2-dichloropropane, 1, 1, 2, 3-tetrachloropropane, and 1, 2, 2, 3-tetrachloropropane, and b) reacting the first feed in the first reaction device to form a second reaction mixture comprising 1, 2-dichloropropane, 1, 1, 2, 3-tetrachloropropane and 1, 2, 2, 3-tetrachloropropane. The invention also relates to a method for preparing tetrachloropropene from the DD mixture, a system for implementing the method for preparing tetrachloropropane and 1, 2-dichloropropane from the DD mixture, and a system for implementing the method for preparing tetrachloropropene from the DD mixture.

Description

Technical Field

[0001] The invention relates to the technical field of fine chemical organic synthesis, and in particular to a method for preparing 1,1,2,3-tetrachloropropene from a DD mixture containing 1,2-dichloropropane, 1,3-dichloropropene and 2,3-dichloropropene. Background Art

[0002] 1,1,2,3-tetrachloro-propene (HCC-1230xa or TCP for short, CAS No.: 10436-39-2) is a colorless, transparent, oily liquid with a chemical formula of C3H2Cl4 and a molecular weight of 179.86. It is easily soluble in organic solvents such as chloroform and carbon tetrachloride and slightly soluble in water.

[0003] 1,1,2,3-Tetrachloropropene is an important chemical intermediate, which can be mainly used to prepare the herbicide wild barley and the new generation of environmentally friendly refrigerant 2,3,3',3"-tetrafluoropropene (HFO-1234yf). HFO-1234yf is a molecule with low global warming potential (GWP). It can be used as an effective refrigerant, fire extinguishing agent, heat transfer medium, propellant, foaming agent, film blowing agent, gas insulation agent, bactericide carrier, polymerization medium, etc. It can also be used as a monomer component for the production of various fluorocarbon materials and various polymers.

[0004] As the application areas and demand for 1,1,2,3-tetrachloropropene continue to expand, the optimization and development of its preparation process has become a difficult problem that researchers need to further overcome, especially the need to produce such compounds using cheap and readily available raw materials and simplified processes.

[0005] At present, the main synthetic routes of 1,1,2,3-tetrachloropropene are:

[0006] (1) 1,1,1,2,3-pentachloropropane is prepared from ethylene and carbon tetrachloride through a series of processes including multi-step chlorination and dehydrochlorination, as well as transposition and dehydration;

[0007] (2) Using 1,2,3-trichloropropane as a raw material, 1,1,2,2,3-pentachloropropane is prepared through a multi-step reaction, and then 1,1,2,3-tetrachloropropene is prepared by removing hydrogen chloride in an alkaline solution;

[0008] (3) Using cis-1,3-dichloropropene (cis-1,3-DCP) as a raw material, 1,1,2,3-tetrachloropropane is obtained by chlorine addition, and mixed trichloropropenes are obtained after dehydrochlorination, and mixed pentachloropropanes are obtained after chlorination, and finally 1,1,2,3-tetrachloropropene is obtained after transposition.

[0009] From the current preparation methods, there are common problems such as long synthesis routes, low production efficiency, large amounts of by-products and "three wastes", harsh operating conditions, high costs, and the need for a large number of separation and purification equipment.

[0010] Patent CN102911006A relates to a method for preparing high-purity low-water tetrachloropropylene, which comprises the following steps: first, pentachloropropane is rectified by a distillation tower, and then liquid alkali and a phase transfer catalyst (quaternary ammonium salt) are added thereto to obtain a crude tetrachloropropylene product, and then the water content is controlled below 80 ppm after water removal, and then the product is rectified by a distillation tower to obtain a high-purity low-water tetrachloropropylene product with a purity of more than 99.5% and a water content of less than 30 ppm. The disadvantage is that the catalyst cannot be recovered and the amount of "three wastes" discharged is large.

[0011] Patent CN107285992B discloses a method of using 1,2-dichloroethylene and chloroform as starting materials, and obtaining 1,1,2,3,3-pentachloropropane through free radical coupling under the catalysis of anhydrous aluminum chloride, anhydrous ferric chloride, and anhydrous zinc chloride, and then conducting gas phase dehydrochlorination under the action of AlCl3 / C, NiCl2 / C, and FeCl3 / C catalysts to obtain 1,1,2,3-tetrachloropropene. Chloroform is a toxic and carcinogenic chemical with high environmental pollution and occupational health hazards. Although the reaction steps of this method are short, the metal catalyst has a large processing capacity, and the remaining metal ions can cause HCC-1230xa to decompose; the high-temperature gas phase dehydrochlorination method has high energy consumption; the free radical reaction is easy to produce by-products, which need to be quenched with water, and the product has high acidity and water content, which makes it difficult to purify the product in the whole process flow, and complicates storage and transportation.

[0012] Patent US8084653 discloses a method for preparing 1,1,2,3-tetrachloropropene, wherein the steps include: (1) 1,2,3-trichloropropane is saponified with 25% sodium hydroxide solution at 73°C to eliminate hydrogen chloride to obtain 2,3-dichloropropene, with a yield of 95.4%, a selectivity of 97.5%, and a product purity of 93% after distillation and purification; (2) 2,3-dichloropropene is then added with chlorine at 10°C to 30°C to obtain 1,2,2,3,3-pentachloropropane, with a yield of 54.4%, a selectivity of 87%, and a product purity of 99% after purification; (3) Finally, 1,2,2,3,3-pentachloropropane is saponified with 25% sodium hydroxide solution to eliminate hydrogen chloride to obtain 1,1,2,3-tetrachloropropene, with a yield of 96%. The disadvantages of this method are long reaction time, low yield, high by-product content, and the need for a large number of separation and purification equipment, which is not conducive to industrial production.

[0013] In summary, although there are many methods for preparing 1,1,2,3-tetrachloropropene, there are problems such as difficult to obtain raw materials, low yield, high energy consumption, catalyst cannot be recycled, and large amount of "three wastes" emissions. Therefore, it is necessary to develop a green, low-cost, and low-energy method for preparing 1,1,2,3-tetrachloropropene.

[0014] When propylene is subjected to high-temperature chlorination to produce 3-chloropropene, a side reaction occurs. A group of mixed organic substances with a higher boiling point than chloropropene are collectively referred to as chloropropene high-boiling products, also known as DD mixtures, which mainly include 1,2-dichloropropane, 1,3-dichloropropene, 2,3-dichloropropene and a small amount of chloropropene. DD mixtures are yellow-brown or greenish oily liquids, flammable, and have a garlic smell. They are often used as soil fumigants and paint solvents. Usually, in industrial DD mixtures, the content of 1,2-dichloropropane is greater than 40%, and the content of dichloropropene (including cis- and / or trans-1,3-dichloropropene and 2,3-dichloropropene) is greater than 30%. Since the boiling points of 1,2-dichloropropane (boiling point: 98°C) and 1,3-dichloropropene (boiling point 104 to 112°C) are very close, it is easy to form azeotropy and difficult to separate and purify.

[0015] Therefore, the development of a process in which DD mixtures are directly used as raw materials for the synthesis of high-value organic intermediates has good application prospects and economic benefits. Summary of the invention

[0016] The purpose of the present invention is to prepare 1,1,2,3-tetrachloropropene using DD mixture as a starting material, thereby greatly reducing the production cost of the target product and realizing the high-value resource recycling of low-value by-products of industrial production, thereby providing space and economic benefits for reducing equipment investment and increasing product added value.

[0017] The first aspect of the present application provides a method for preparing tetrachloropropane and 1,2-dichloropropane from a DD mixture, the method comprising the following steps:

[0018] a) allowing a first feed to enter the first reaction device through an inlet of the first reaction device, wherein:

[0019] The first feed comprises DD mixture and chlorine,

[0020] The first reaction device is a microchannel reactor,

[0021] The DD mixture contains 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene;

[0022] b) reacting the first feed in the first reaction unit to form a first reaction mixture, wherein the first reaction mixture comprises 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0023] The second aspect of the present application provides a method for preparing tetrachloropropylene, the method comprising the following steps:

[0024] a) allowing a first feed to enter the first reaction device through an inlet of the first reaction device, wherein:

[0025] The first feed comprises DD mixture and chlorine,

[0026] The first reaction device is a microchannel reactor,

[0027] The DD mixture contains 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene;

[0028] b) reacting the first feed in the first reaction unit to form a first reaction mixture, the first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane;

[0029] c) passing the first reaction mixture into a first purification unit to form a first stream and a second stream, wherein the first stream comprises 1,2-dichloropropane and the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane;

[0030] d) obtaining tetrachloropropene from the second stream.

[0031] The third aspect of the present application provides a system for operating the method for preparing tetrachloropropane and 1,2-dichloropropane from a DD mixture according to the first aspect of the present application, wherein the system comprises a first reaction device as a microchannel reactor, wherein:

[0032] The first reaction device is configured to have at least one inlet and at least one outlet;

[0033] At least one of the inlets of the first reaction device is configured to receive a first feed, the first feed comprising a DD mixture and chlorine gas, the DD mixture comprising 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene;

[0034] The first reaction apparatus is configured to react the first feed to form a first reaction mixture, the first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane;

[0035] At least one of the outlets of the first reaction device is configured to discharge the first reaction mixture.

[0036] The fourth aspect of the present application provides a system for operating the method for preparing tetrachloropropene according to the second aspect of the present application, the system comprising a first reaction device as a microchannel reactor, a first purification device, and a third reaction device, wherein:

[0037] The first reaction device is configured to have at least one inlet and at least one outlet; at least one of the inlets of the first reaction device is configured to receive a first feed, the first feed comprises a DD mixture and chlorine gas, the DD mixture comprises 1,2-dichloropropane, 1,3-dichloropropene and 2,3-dichloropropene; the first reaction device is configured to react the first feed to form a first reaction mixture, the first reaction mixture comprises 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; at least one of the outlets of the first reaction device is configured to discharge the first reaction mixture;

[0038] The first purification device comprises at least one inlet and at least one outlet, at least one of the inlets of the first purification device is configured to receive the first reaction mixture from the first reaction device, the first purification device is configured to purify the first reaction mixture to form a first stream and a second stream, the first stream comprises 1,2-dichloropropane, the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane, the first outlet of the first purification device is configured to discharge the first stream, and the second outlet of the first purification device is configured to discharge the second stream;

[0039] The third reaction device comprises at least one inlet and at least one outlet, at least one of the inlets of the third reaction device is configured to receive the second stream from the first purification device and form tetrachloropropene.

[0040] The fifth aspect of the present application provides a composition comprising tetrachloropropane and 1,2-dichloropropane prepared by the method according to the first aspect of the present application.

[0041] The sixth aspect of the present application provides a tetrachloropropene product obtained by the method according to the second aspect of the present application.

[0042] The method provided in the present application makes full use of the components in the DD mixture, simplifies the process steps, and reduces equipment investment, thereby preparing tetrachloropropane and even 1,1,2,3-tetrachloropropene.

[0043] The present application adopts a microchannel reactor to carry out the first chlorination reaction, and utilizes the advantage of the high mass transfer rate of the microchannel to reduce the contact time of the raw materials, efficiently control the rates of different chlorination reactions, and at the same time reduce the occurrence of over-chlorination, effectively control the conversion of dichloropropylene in the raw materials into tetrachloropropane, and inhibit the chlorine substitution reaction of 1,2-dichloropropane.

[0044] The method of the present application is conducive to reducing the complexity of the components after the first chlorination reaction, thereby improving the distillation separation yield of the target component. In addition, the microchannel reaction can significantly reduce the reaction time and reduce the production energy consumption, so it has good economic benefits and industrial application potential. DETAILED DESCRIPTION

[0045] "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 inclusive or exclusive of end values, and can be arbitrarily combined, i.e., any lower limit can be combined with any upper limit to form a range. For example, if a range of 60 to 120 and 80 to 110 is listed for a particular parameter, it is understood that a range of 60 to 110 and 80 to 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 range can all be expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4 and 2 to 5. In this application, unless otherwise specified, the numerical range "a to b" 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 to 5" means that all real numbers between "0 to 5" are listed in this document, and "0 to 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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).

[0052] Herein, unless otherwise specified, percentage (%) or part refers to percentage by weight or part by weight relative to the composition.

[0053] Herein, if there is no contrary description, the sum of the contents of the various components in the composition is 100%.

[0054] Herein, if there is no contrary description, the sum of the parts of each component in the composition may be 100 parts by weight.

[0055] 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.

[0056] If not specifically stated, the terms "a" or "an" used in the present specification means "at least one".

[0057] Herein, unless otherwise stated, all reactions are carried out at normal temperature and pressure.

[0058] In the context of this application, the expression "N% i；X ” means the molar fraction of component X in a stream / mixture; wherein i is 0 and means the molar fraction of component X in the feed; wherein i is a, b, c, d, e, or f and means the molar fraction of component X in the stream at the end of step a), b), c), d), e), or f).

[0059] Expression "ΣN% i；X , where X is...” can be used to express the sum of the mole fractions of the components mentioned in a stream / mixture, where i has the same meaning as described above.

[0060] In the context of this application, the expression "A i；X ” means the peak area of ​​component X when analyzing a stream / mixture by chromatography; the expression “ΣA i；X , where X is... " can be used to express the sum of the peak areas of the components mentioned when analyzing a certain stream / mixture by chromatography (such as liquid chromatography, gas chromatography). The meaning expressed by i is as described above.

[0061] In the context of this application, the expression "R i；X ” means the mass flow rate of component X or stream X, R i；X kg·s -1 The meaning of i is as described above.

[0062] In the context of this application, the expression " i；X ” means the molar flow rate of component X or stream X, r i；X With mol·s -1 The meaning of i is as described above.

[0063] Method for preparing tetrachloropropane and 1,2-dichloropropane from DD mixture

[0064] The first aspect of the present application relates to a method for preparing tetrachloropropane and 1,2-dichloropropane from a DD mixture, the method comprising the following steps:

[0065] a) allowing a first feed to enter the first reaction device through an inlet of the first reaction device, wherein:

[0066] The first feed comprises DD mixture and chlorine,

[0067] The first reaction device is a microchannel reactor, and

[0068] The DD mixture contains 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene;

[0069] b) reacting the first feed in the first reaction unit to form a first reaction mixture, wherein the first reaction mixture comprises 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0070] Step a)

[0071] In the method of the first aspect of the present application, step a) involves allowing a first feed to enter the first reaction device through an inlet of the first reaction device, the first feed comprising a DD mixture and chlorine, the first reaction device being a microchannel reactor, and the DD mixture comprising 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene.

[0072] [First feed]

[0073] The first material used in the first aspect of the present application comprises a DD mixture and chlorine gas.

[0074] [DD mixture]

[0075] Generally, the DD mixture in the present application is a conventional industrial product, which is derived from the by-product of propylene chlorination and is usually treated as chlorine-containing waste. In a non-limiting example of the present application, the DD mixture is provided by Jiangsu Ruiheng New Materials Co., Ltd.

[0076] DD mixture mainly contains 1,2-dichloropropane, 1,3-dichloropropylene, 2,3-dichloropropylene and a small amount of chloropropylene and other mixed components. Generally, in industrial DD mixture, the content of 1,2-dichloropropane is greater than 40%, and the content of dichloropropylene (including cis- and / or trans-1,3-dichloropropylene and 2,3-dichloropropylene) is greater than 30%.

[0077] As a non-limiting example, the content of 1,2-dichloropropane in the DD mixture that can be used in the present application can be 40 to 75% by weight, based on the total weight of the DD mixture. For example, the content of 1,2-dichloropropane in the DD mixture that can be used in the present application can be 40% by weight, or 42% by weight, or 44% by weight, or 46% by weight, or 48% by weight, or 50% by weight, or 52% by weight, or 54% by weight, or 56% by weight, or 58% by weight, or 60% by weight, based on the total weight of the DD mixture.

[0078] As a non-limiting example, in the DD mixture that can be used in the present application, the content of dichloropropylene can be 25 to 60% by weight, based on the total weight of the DD mixture. For example, in the DD mixture that can be used in the present application, the amount of dichloropropylene can be 25% by weight, or 26% by weight, or 28% by weight, or 30% by weight, or 32% by weight, or 34% by weight, or 36% by weight, or 38% by weight, or 40% by weight, or 42% by weight, or 44% by weight, or 46% by weight, or 48% by weight, or 50% by weight, based on the total weight of the DD mixture.

[0079] As a non-limiting example, in the DD mixture that can be used in the present application, the content of 1,3-dichloropropene can be 20 to 50% by weight, based on the total weight of the DD mixture. For example, in the DD mixture that can be used in the present application, the content of 1,3-dichloropropene can be 20% by weight, or 22% by weight, or 24% by weight, or 26% by weight, or 28% by weight, or 30% by weight, or 32% by weight, or 34% by weight, or 36% by weight, or 38% by weight, or 40% by weight, based on the total weight of the DD mixture.

[0080] As a non-limiting example, in the DD mixture that can be used in the present application, the content of cis-1,3-dichloropropene can be 10 to 25% by weight, based on the total weight of the DD mixture. For example, in the DD mixture that can be used in the present application, the content of cis-1,3-dichloropropene can be 10% by weight, or 12% by weight, or 14% by weight, or 16% by weight, or 18% by weight, or 20% by weight, based on the total weight of the DD mixture.

[0081] As a non-limiting example, in the DD mixture that can be used in the present application, the content of trans-1,3-dichloropropene can be 10 to 25% by weight, based on the total weight of the DD mixture. For example, in the DD mixture that can be used in the present application, the content of trans-1,3-dichloropropene can be 10% by weight, or 12% by weight, or 14% by weight, or 16% by weight, or 18% by weight, or 20% by weight, based on the total weight of the DD mixture.

[0082] As a non-limiting example, in the DD mixture that can be used in the present application, the content of 2,3-dichloropropene can be 5 to 10% by weight, based on the total weight of the DD mixture. For example, in the DD mixture that can be used in the present application, the content of 2,3-dichloropropene can be 5% by weight, or 6% by weight, or 7% by weight, or 8% by weight, or 9% by weight, or 10% by weight, based on the total weight of the DD mixture.

[0083] According to one embodiment, the DD mixture that can be used in the present application may further contain allyl chloride. According to one embodiment, the content of allyl chloride in the DD mixture that can be used in the present application may be 0 to 10 wt%.

[0084] The contents of 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene in the DD mixture can be calculated by chromatography and the following formula 1:

[0085]

[0086] wherein X is 1,2-dichloropropane, 1,3-dichloropropene, 2,3-dichloropropene, and allyl chloride (if present).

[0087] Correspondingly, in Formula 1

[0088] ∑A 0；X =A 0；1,2-二氯丙烷 +A 0；1,3-二氯丙烯 +A 0；2,3-二氯丙烯 +A 0；氯丙烯

[0089] For 1,3-dichloropropene, A 0；1,3-二氯丙烯 It represents the sum of the areas of cis-1,3-dichloropropane and trans-1,3-dichloropropene in the chromatogram.

[0090] [Chlorine]

[0091] Chlorine gas can be obtained from any source known to those skilled in the art. In a non-limiting example, chlorine gas that can be used in the present application can be obtained from Jiangsu Ruiheng New Materials Co., Ltd.

[0092] According to one embodiment, the molar ratio of chlorine to dichloropropylene in the first feed is 0.5 to 5, or 0.6 to 4, or 0.7 to 3, or 0.8 to 2. For example, the molar ratio of chlorine to dichloropropylene in the first feed may be 0.5, or 0.6, or 0.7, or 0.8, or 0.9, or 0.95, or 1, 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, 1.10, or 1.2, or 1.3, or 1.4, or 1.5, or 1.6, or 1.7, or 1.8, or 1.9, or 2.0 , or 2.1, or 2.2, or 2.3, or 2.4, or 2.5, or 2.6, or 2.7, or 2.8, or 2.9, or 3.0, or 3.1, or 3.2, or 3.3, or 3.4, or 3.5, or 3.6, or 3.7, or 3.8, or 3.9, or 4.0, or 4.1, or 4.2, or 4.3, or 4.4, or 4.5, or 4.6, or 4.7, or 4.8, or 4.9, or 5.0.

[0093] If the method described in the first aspect of the present application is carried out in an intermittent manner, the molar ratio of chlorine to dichloropropylene can be calculated by the feed mass of chlorine and the feed mass of dichloropropylene in the DD mixture. The feed mass of dichloropropylene in the DD mixture can be calculated by the feed mass of the DD mixture and the content N% of each component in the DD mixture measured by chromatography as described above. 0；X Calculated.

[0094] If the method of the first aspect of the present application is carried out in a continuous manner, the molar ratio of chlorine to dichloropropylene can be determined by the molar flow rate of chlorine r 0；Cl2 The molar flow rate of dichloropropylene in the mixture with DD 0；二氯丙烯 Specifically, as shown in Formula 2,

[0095]

[0096] Where X is 1,2-dichloropropane, 1,3-dichloropropylene, 2,3-dichloropropylene, and allyl chloride (if present). The mass flow rate of chlorine gas and the mass flow rate of DD mixture can be obtained by a metering pump.

[0097] How step a) is carried out

[0098] The first feed can enter the first reactor as a microchannel reactor in a manner known to those skilled in the art. As a non-limiting example, the first feed can enter the first reactor via a flow pump. The DD mixture and chlorine in the first feed can be mixed and fed to the microchannel reactor together, or can enter the microchannel reactor via separate inlets.

[0099] The mass flow rate of the DD mixture can be 0.1 to 100 g / min. In non-limiting examples, the mass flow rate of the DD mixture can be 0.1 g / min, or 0.2 g / min, or 0.5 g / min, or 1.0 g / min, or 2.0 g / min, or 5.0 g / min, or 8 g / min, or 10 g / min, or 12 g / min, or 14 g / min, or 16 g / min, or 18 g / min, or 20 g / min, or 25 g / min, or 30 g / min, or 35 g / min, or 40 g / min, or 45 g / min, or 50 g / min, or 55 g / min, or 60 g / min, or 65 g / min, or 70 g / min, or 75 g / min, or 80 g / min, or 85 g / min, or 90 g / min, or 95 g / min, or 100 g / min.

[0100] The mass flow rate of chlorine gas may be 0.1 to 20 g / min. In non-limiting examples, the mass flow rate of chlorine gas may be 0.1 g / min, or 0.2 g / min, or 0.5 g / min, or 1.0 g / min, or 2.0 g / min, or 5.0 g / min, or 8 g / min, or 10 g / min, or 12 g / min, or 14 g / min, or 16 g / min, or 18 g / min, or 20 g / min.

[0101]

Microchannel reactor

[0102] In the context of this application, the terms "microchannel reactor", "microflow reactor", "microreactor", "microstructure reactor", "microfluidic reactor", "tubular reactor" and the like can be used interchangeably.

[0103] Microchannel reactors belong to the field of micro-processing engineering. They are usually continuous fluid reactors with the advantages of high heat transfer efficiency, fast reaction speed, high yield, good safety and stability.

[0104] The material of channel in micro passage reactor is not particularly limited. As non-limiting example, the material of channel can be selected from: stainless steel, silicon carbide ceramics etc. The channel inner diameter is not particularly limited in micro passage reactor. As non-limiting example, the channel inner diameter range can be no more than 5mm, or no more than 4mm, or no more than 3mm, or no more than 2mm, or no more than 1mm, or no more than 0.9mm, or no more than 0.8mm, or no more than 0.7mm, or no more than 0.6mm, or no more than 0.5mm, or no more than 0.4mm, or no more than 0.3mm, or no more than 0.2mm, or no more than 0.1mm.

[0105] The channel length in the microchannel reactor is not particularly limited. As a non-limiting example, the channel length can be 50 to 200 cm, for example, the channel length can be 50 cm, or 100 cm, or 150 cm, or 200 cm.

[0106] The specific surface area of ​​the channels in the microchannel reactor is not particularly limited. As a non-limiting example, the specific surface area of ​​the channels may be 1000 to 50000 m 2 / m 3 , or 5000 to 30000m 2 / m 3 , or 10000 to 20000m 2 / m 3 .

[0107] The microchannel reactor comprises at least one outlet and at least one inlet. In a non-limiting example, the microchannel reactor has 1 to 5, or 1 to 3, or 1 to 2 inlets.

[0108] The microchannel reactor that can be used in the present application can be commercially obtained, for example, from Hangzhou Shenshi Energy Saving Technology Co., Ltd. under the model number ss-0010wr-ti-p, or from Corning Reactor Technology Co., Ltd. under the model number G1 SiC.

[0109] Step b)

[0110] The first feed enters into a first reaction device which is a microchannel reactor for reaction to form a first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0111] The reaction temperature in the microchannel reactor can be 15 to 100° C. For example, the reaction temperature in the microchannel reactor can be 15° C., or 20° C., or 25° C., or 30° C., or 35° C., or 40° C., or 45° C., or 50° C., or 55° C., or 60° C., or 65° C., or 70° C., or 75° C., or 80° C., or 85° C., or 90° C., or 95° C., or 100° C.

[0112] The total residence time of the first feed in the microchannel reactor can be 10 to 300 seconds, for example, the total residence time can be 10 seconds, or 20 seconds, or 30 seconds, or 40 seconds, or 50 seconds, or 60 seconds, or 70 seconds, or 80 seconds, or 90 seconds, or 100 seconds, or 110 seconds, or 120 seconds, or 130 seconds, or 140 seconds, or 150 seconds, or 160 seconds, or 170 seconds, or 180 seconds, or 190 seconds, or 200 seconds, or 210 seconds, or 220 seconds, or 230 seconds, or 240 seconds, or 250 seconds, or 260 seconds, or 270 seconds, or 280 seconds, or 290 seconds, or 300 seconds.

[0113] In a preferred embodiment, the total residence time of the first feed in the microchannel reactor is 10 to 120 seconds. In a more preferred embodiment, the total residence time of the first feed in the microchannel reactor is 30 to 90 seconds.

[0114] The microchannel reactor may have 1 or more stages. In a preferred embodiment, the microchannel reactor may have 1 to 5 stages. In a non-limiting example, the microchannel reactor may have 1, or 2, or 3, or 4, or 5 stages.

[0115] In the case where the microchannel reactor has more than one stage, the temperature of each section in the microchannel reactor may be the same or different. In a preferred embodiment, the temperature of the nth section of the microchannel is greater than or equal to the temperature of the n-1th section. In a non-limiting example, the temperature of the nth section of the microchannel may be 0 to 10°C higher than the temperature of the n-1th section. For example, the temperature of the nth section of the microchannel may be 0°C, or 2°C, or 4°C, or 6°C, or 8°C, or 10°C higher than the temperature of the n-1th section.

[0116] In a preferred embodiment, in the method of the first aspect of the present application, the microchannel reactor has two stages, and step b) is carried out as follows: wherein in the first stage of the microchannel reactor, the reaction is carried out at a temperature T1, and the residence time in the first stage is t1, and then in the second stage of the microchannel reactor, the reaction is carried out at a temperature T2, and the residence time in the second stage is t2.

[0117] According to one embodiment, t1 is the ratio of the total residence time of the first logistics in the microchannel reactor is not more than 100% and greater than 0%. For example, t1 can be 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%.

[0118] According to one embodiment, T1 is 30 to 60°C, or 35 to 55°C, or 40 to 50°C.

[0119] According to one embodiment, T2 is 40 to 70°C, or 45 to 65°C, or 50 to 60°C, provided that the temperature of the second stage is higher than that of the first stage.

[0120] [First reaction mixture]

[0121] According to the first aspect of the present application, after step b), a first reaction mixture is obtained, wherein the first reaction mixture comprises 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0122] Unexpectedly, the applicant found that the chlorination of 1,2-dichloropropane in the DD mixture can be significantly suppressed by using a microchannel reactor, while at the same time ensuring that the dichloropropene in the DD mixture is highly selectively converted into 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane. The boiling points of 1,2-dichloropropane and the two tetrachloropropanes are significantly different, so that 1,2-dichloropropane and the two tetrachloropropanes can be easily separated, which is convenient for further processing or product collection in subsequent processes.

[0123] According to one embodiment, after step b), the conversion rate of 1,2-dichloropropane in the DD mixture is less than 5%, or less than 4%, or less than 3%, or less than 2%, or less than 1%, or less than or equal to 0.5%. For example, the conversion rate of 1,2-dichloropropane in the DD mixture is 0.001%, or 0.002%, or 0.005%, or 0.01%, or 0.02%, or 0.05%, or 0.1%, or 0.2%, or 0.3%, or 0.4%, or 0.5%, or 0.6%, or 0.7%, or 0.8%, or 0.9%, or 1.0%, or 1.2%, or 1.4%, or 1.6%, or 1.8%, or 2.0%.

[0124] Conversion rate of 1,2-dichloropropane b；1,2-二氯丙烷 It can be calculated by formula 3:

[0125]

[0126] Where N% 0；1,2-二氯丙烷 The calculation method of is as described in formula 1; N% b；1,2-二氯丙烷 It can be calculated by the following formula:

[0127]

[0128] wherein X is 1,2-dichloropropane, 1,3-dichloropropene, 2,3-dichloropropene, 1,1,2,3-tetrachloropropane, 1,2,2,3-tetrachloropropane, and other carbon-containing components (if present, such as allyl chloride, pentachloropropane).

[0129] According to one embodiment, after step b), the conversion rate of dichloropropylene in the DD mixture is greater than 80%, or greater than 90%, or greater than 95%, or greater than 98%, or greater than 99%. For example, the conversion rate of dichloropropylene in the DD mixture can be 80%, or 81%, or 82%, or 83%, or 84%, or 85%, or 86%, or 87%, or 88%, or 89%, or 90%, or 91%, or 92%, or 93%, or 94%, or 95%, or 96%, or 97%, or 98%, or 99%, or 99.5%, or 99.8%, or 99.9%.

[0130] Conversion rate of dichloropropylene b；二氯丙烯 It can be calculated in a similar way to Equation 3, as shown in Equation 4:

[0131] The conversion rate of 1,2-dichloropropane can be calculated by formula 3:

[0132]

[0133] in

[0134]

[0135] wherein X is 1,2-dichloropropane, 1,3-dichloropropene, 2,3-dichloropropene, and allyl chloride (if present);

[0136]

[0137] wherein Y is 1,2-dichloropropane, 1,3-dichloropropene, 2,3-dichloropropene, 1,1,2,3-tetrachloropropane, 1,2,2,3-tetrachloropropane, and other carbon-containing components (if present, such as allyl chloride, pentachloropropane).

[0138] According to one embodiment, after step b), the yield of tetrachloropropane based on the dichloropropene in the DD mixture is greater than 80%, or greater than 90%, or greater than 95%, or greater than 98%, or greater than 99%. For example, the yield of tetrachloropropane in the DD mixture can be 80%, or 81%, or 82%, or 83%, or 84%, or 85%, or 86%, or 87%, or 88%, or 89%, or 90%, or 91%, or 92%, or 93%, or 94%, or 95%, or 96%, or 97%, or 98%, or 99%, or 99.5%, or 99.8%, or 99.9%, based on the dichloropropene in the DD mixture.

[0139] Yield of Tetrachloropropane b；四氯丙烷 It can be calculated as follows:

[0140]

[0141] wherein X is 1,2-dichloropropane, 1,3-dichloropropene, 2,3-dichloropropene, 1,1,2,3-tetrachloropropane, 1,2,2,3-tetrachloropropane, and other carbon-containing components (if present, such as allyl chloride, pentachloropropane).

[0142] According to one embodiment, in the first reaction mixture, the molar ratio of tetrachloropropane to dichloropropylene is at least 1000, or at least 2000, or at least 5000, or at least 10000. For example, in the first reaction mixture, the molar ratio of tetrachloropropane to dichloropropylene is 1000, or 2000, or 3000, or 4000, or 5000, or 6000, or 7000, or 8000, or 9000, or 10000, or 20000, or 30000, or 40000, or 50000, or 60000, or 70000, or 80000, or 90000, or 100000, or 200000, or 500000.

[0143] The molar ratio of tetrachloropropane to dichloropropylene can be calculated by the ratio of the peak area of ​​tetrachloropropane to the peak area of ​​dichloropropylene in the chromatogram, that is,

[0144]

[0145] Preferred step c) first purification

[0146] According to a preferred embodiment, the method of the first aspect of the present application further comprises the following steps:

[0147] c) passing the first reaction mixture into a first purification unit to form a first stream and a second stream, wherein the first stream comprises 1,2-dichloropropane and the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0148] The purification in step c) can be performed by means well known to those skilled in the art, including but not limited to distillation, rectification or a combination thereof, as described in patent application CN112979413A, which is incorporated herein by reference in its entirety.

[0149] According to one embodiment, the content of 1,2-dichloropropane in the first stream is at least 50% by weight, or at least 60% by weight, or at least 70% by weight, or at least 80% by weight, or at least 90% by weight, or at least 95% by weight, or at least 96% by weight, or at least 97% by weight, or at least 98% by weight, or at least 99% by weight, relative to the total weight of the first stream.

[0150] The content of 1,2-dichloropropane in the first stream can be calculated by chromatography using a similar method to that described above.

[0151] According to one embodiment, in the second stream, the mass fraction of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane is at least 50 wt%, or at least 60 wt%, or at least 70 wt%, or at least 80 wt%, or at least 90 wt%, or at least 95 wt%, or at least 96 wt%, or at least 97 wt%, or at least 98 wt%, or at least 99 wt%, relative to the total weight of the second stream.

[0152] The mass fractions of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane can be calculated by chromatography, for example, by formula 5:

[0153]

[0154] Where N% b；X The calculation method of is as described above.

[0155] Preferred step d) second chlorination

[0156] According to a preferred embodiment, the method of the first aspect of the present application further comprises the following steps:

[0157] d) allowing the first stream obtained in step c) to enter a second reaction device to obtain a third stream comprising 1,2-dichloropropane, 1,2,3-trichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0158] [Second reaction device]

[0159] The second reaction device may be a reaction device well known to those skilled in the art. In some embodiments, the second reaction device may be a microchannel reactor or a reactor. In other embodiments, the second reaction device is a reactor.

[0160] According to one embodiment, the temperature in the second reaction device is -30 to 30° C. For example, the temperature in the second reaction device may be -30° C., or -25° C., or -20° C., or -15° C., or -10° C., or -5° C., or 0° C., or 5° C., or 10° C., or 15° C., or 20° C., or 25° C., or 30° C.

[0161] According to one embodiment, the total reaction time in the second reaction unit is 1 to 30 hours, or 1 to 20 hours. For example, the total reaction time in the second reaction unit is 1 hour, or 2 hours, or 3 hours, or 4 hours, or 5 hours, or 6 hours, or 7 hours, or 8 hours, or 9 hours, or 10 hours, or 11 hours, or 12 hours, or 13 hours, or 14 hours, or 15 hours, or 16 hours, or 17 hours, or 18 hours, or 19 hours, or 20 hours, or 21 hours, or 22 hours, or 23 hours, or 24 hours, or 25 hours, or 26 hours, or 27 hours, or 28 hours, or 29 hours, or 30 hours.

[0162] According to one embodiment, the second reaction device comprises one or more stages, for example, the second reaction device may have 1 to 5 stages. In a non-limiting example, the second reaction device may have 1, or 2, or 3, or 4, or 5 stages.

[0163] In the embodiment where the second reaction device has 2 or more stages, the temperature of each stage may be the same or different. According to a preferred embodiment, in the second reaction device, the temperature of the nth stage is greater than or equal to the reaction temperature of the n-1th stage.

[0164] According to a preferred embodiment, in the second reaction device, the reaction temperature of the nth stage is strictly greater than the reaction temperature of the n-1th stage.

[0165] In the embodiment where the second reaction device has 2 or more stages, the reaction time of each stage may be the same or different. According to a preferred embodiment, in the second reaction device, the reaction time of the nth stage is greater than or equal to the reaction time of the n-1th stage.

[0166] According to a preferred embodiment, the reaction time of each stage in the second reaction device is equal.

[0167] According to a preferred embodiment, the second reaction device has two stages, and the step d) is carried out as follows: the first stream obtained in step c) enters the second reaction device, reacts at temperature T3 for t3 in the first stage, and then reacts at temperature T4 for time t4 in the second stage.

[0168] According to an exemplary embodiment, T3 is -30 to 0°C, or -20 to 0°C, or -15 to -5°C.

[0169] According to an exemplary embodiment, T4 is -5 to 20°C, or -5 to 15°C, or -5 to 10°C, or -5 to 5°C.

[0170] According to an exemplary embodiment, t3 is 1 to 16 hours, or 2 to 14 hours, or 4 to 12 hours.

[0171] According to an exemplary embodiment, t4 is 1 to 16 hours, or 2 to 14 hours, or 4 to 12 hours.

[0172] The catalyst that can be used in the second reaction device includes but is not limited to: Al powder, Fe powder, AlCl3, etc. According to a preferred embodiment, the catalyst used in the second reaction device is Al powder.

[0173] According to one embodiment, the mass fraction of the catalyst relative to the third stream is 0.1 to 3 wt%.

[0174] According to a preferred embodiment, the reaction in the second reaction device is carried out under illumination conditions. The light source of the illumination includes a visible light source, an ultraviolet light source or a natural light source or a combination thereof. Preferably, the light source of the illumination is an ultraviolet light source.

[0175] In a preferred embodiment, the intensity of the illumination is 10 to 300 W. For example, the intensity of the light source may be 10 W, or 50 W, or 100 W, or 150 W, or 200 W, or 250 W, or 300 W.

[0176] The equivalent ratio of the first logistics and chlorine entering the second reaction device may be 1:0.5 to 1:1.5. For example, the equivalent ratio of the first logistics and chlorine entering the second reaction device may be 1:0.5, or 1:0.6, or 1:0.7, or 1:0.8, or 1:0.9, or 1:1, or 1:1.1, or 1:1.2, or 1:1.3, or 1:1.4, or 1:1.5.

[0177] The equivalent ratio of the first stream and the chlorine gas entering the second reaction device can be obtained in a manner similar to that in step a).

[0178] The applicant has found that by preferably using Al or Fe powder or a mixture instead of the commonly used AlCl3 as a catalyst, the 1,2-dichloropropane whose reaction is inhibited in the first reactor can be highly selectively converted into tetrachloropropane via highly selective conversion into 1,2,3-trichloropropane at low temperature. This makes it possible to fully utilize the raw materials in the DD mixture, reducing the production cost and environmental friendliness of the method of the first aspect of the present application.

[0179] [Third Party Logistics]

[0180] The third stream obtained in step d) comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane and optionally 1,2-dichloropropane, 1,2,3-trichloropropane.

[0181] According to a preferred embodiment, the molar content of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane in the third stream is at least 50 mol%, relative to the total molar content of halogenated propanes in the third stream. For example, the molar content of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane in the third stream may be at least 55 mol%, or at least 60 mol%, or at least 65 mol%, or at least 70 mol%, or at least 75 mol%, or at least 80 mol%, or at least 85 mol%, or at least 90 mol%, or at least 91 mol%, or at least 92 mol%, or at least 93 mol%, or at least 94 mol%, or at least 95 mol%, or at least 96 mol%, or at least 97 mol%, or at least 98 mol%, or at least 99 mol%, or at least 99.5 mol%, relative to the total molar content of halogenated propanes in the third stream.

[0182] According to a preferred embodiment, the third stream further contains pentachloropropane.

[0183] According to a preferred embodiment, the molar content of pentachloropropane in the third stream is no more than 20 mole%, relative to the total molar content of halogenated propane in the third stream. For example, the molar content of pentachloropropane in the third stream may be no more than 20 mole%, or no more than 18 mole%, or no more than 16 mole%, or no more than 14 mole%, or no more than 12 mole%, or no more than 10 mole%, or no more than 9 mole%, or no more than 8 mole%, or no more than 7 mole%, or no more than 6 mole%, or no more than 5 mole%, or no more than 4 mole%, or no more than 3 mole%, or no more than 2 mole%, or no more than 1 mole%, relative to the total molar content of halogenated propane in the third stream.

[0184] The mole fraction of each component can be calculated in a manner similar to that described above.

[0185] Preferred step e) second purification

[0186] According to a preferred embodiment, the method of the first aspect of the present application further comprises the following steps:

[0187] e) passing the third stream obtained in step d) into a second purification unit to form a fourth stream, wherein the fourth stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0188] The purification in step e) can be carried out by means well known to those skilled in the art, including but not limited to rectification, distillation or a combination thereof, as described in patent application CN112979413A, which is incorporated herein by reference in its entirety.

[0189] According to a preferred embodiment, in the fourth stream, the mass fraction of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane is at least 50 wt%, or at least 60 wt%, or at least 70 wt%, or at least 80 wt%, or at least 90 wt%, or at least 95 wt%, or at least 96 wt%, or at least 97 wt%, or at least 98 wt%, or at least 99 wt%, relative to the total weight of the fourth stream.

[0190] According to a preferred embodiment, in step e) a fifth stream is also formed, said fifth stream comprising 1,2-dichloropropane and 1,2,3-trichloropropane.

[0191] According to a preferred embodiment, the mass fraction of 1,2-dichloropropane and 1,2,3-trichloropropane in the fifth stream is at least 50 wt%, or at least 60 wt%, or at least 70 wt%, or at least 80 wt%, or at least 90 wt%, or at least 95 wt%, or at least 96 wt%, or at least 97 wt%, or at least 98 wt%, or at least 99 wt%, relative to the total weight of the fifth stream.

[0192] According to a preferred embodiment, in step e), a sixth stream is also formed, said sixth stream comprising 1,1,2,2,3-pentachloropropane and 1,1,1,2,3-pentachloropropane.

[0193] According to a preferred embodiment, the mass fraction of 1,1,2,2,3-pentachloropropane and 1,1,1,2,3-pentachloropropane in the sixth stream is at least 50 wt%, or at least 60 wt%, or at least 70 wt%, or at least 80 wt%, or at least 90 wt%, or at least 95 wt%, or at least 96 wt%, or at least 97 wt%, or at least 98 wt%, or at least 99 wt%, relative to the total weight of the sixth stream.

[0194] According to a preferred embodiment, the method of the first aspect of the present application further comprises the following steps:

[0195] f) returning the fifth stream obtained in step e) to the second reaction device.

[0196] Step f) can be performed by any means known to those skilled in the art.

[0197] Process for producing tetrachloropropene

[0198] A second aspect of the present application relates to a method for preparing tetrachloropropene, the method comprising the following steps:

[0199] a) allowing a first feed to enter the first reaction device through an inlet of the first reaction device, wherein:

[0200] The first feed comprises DD mixture and chlorine,

[0201] The first reaction device is a microchannel reactor, and

[0202] The DD mixture contains 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene;

[0203] b) reacting the first feed in the first reaction unit to form a first reaction mixture, the first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane;

[0204] c) passing the first reaction mixture into a first purification unit to form a first stream and a second stream, wherein the first stream comprises 1,2-dichloropropane and the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; and

[0205] d) obtaining tetrachloropropene from the second stream.

[0206] Wherein, steps a)-c) can be implemented by a method that is the same as or similar to the method described in the first aspect of the present application.

[0207] Step d) of the method of the second aspect of the present application can be implemented by methods well known to those skilled in the art. In a non-limiting example, step d) of the method of the second aspect of the present application includes the following sub-steps:

[0208] d1) allowing the second stream to enter a first dehydrochlorination device, and introducing a first liquid caustic soda and a first phase transfer catalyst into the first dehydrochlorination device;

[0209] d2) reacting the second stream in the first dehydrochlorination unit to form a seventh stream comprising mainly 1,2,3-trichloropropene, 1,1,3-trichloropropene and 2,3,3-trichloropropene;

[0210] d3) allowing the seventh stream to enter a second chlorination reactor and introducing chlorine gas into the second chlorination reactor;

[0211] d4) reacting the seventh stream in the second chlorination reactor to form an eighth stream, wherein the eighth stream comprises tetrachloropropane and / or pentachloropropane;

[0212] d5) optionally, passing the eighth stream into a third purification unit to form a tenth stream comprising mainly 1,2,2,3-tetrachloropropane, and a ninth stream comprising mainly 1,1,1,2,3-pentachloropropane and 1,1,2,2,3-pentachloropropane;

[0213] d6) optionally, returning the tenth stream to the first dehydrochlorination reaction unit;

[0214] d7) allowing the eighth stream or the ninth stream to enter a second dehydrochlorination reaction device, and introducing a second liquid alkali and a second phase transfer catalyst into the second dehydrochlorination reaction device;

[0215] d8) forming an eleventh stream comprising mainly 1,1,2,3-tetrachloropropene and 2,3,3,3-tetrachloropropene in the second dehydrochlorination reaction unit;

[0216] d9) Optionally, subjecting the eleventh stream to a photocatalytic isomerization, wherein 2,3,3,3-tetrachloropropene is converted into 1,1,2,3-tetrachloropropene.

[0217] In a preferred embodiment, step d) of the method of the second aspect of the present application can be implemented by using the method described in patent application CN116444339A.

[0218] The first feed, the first reaction mixture, the first logistics and the second logistics described in the second aspect of the present application are as described in the first aspect of the present application.

[0219] According to a preferred embodiment, the method of the second aspect of the present application further comprises the following steps:

[0220] e) allowing the first stream obtained in step c) to enter a second reaction device to obtain a third stream comprising 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane, and optionally 1,2-dichloropropane and 1,2,3-trichloropropane.

[0221] Step e) of the method described in the second aspect of the present application can be implemented by the same or similar method as step d) described in the first aspect of the present application. The third logistics is as described in the first aspect of the present application.

[0222] According to a preferred embodiment, the method of the second aspect of the present application further comprises the following steps:

[0223] f) passing the third stream obtained in step e) into a second purification unit to form a fourth stream, wherein the fourth stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0224] Step f) of the method described in the second aspect of the present application can be implemented by the same or similar method as step e) described in the first aspect of the present application. The third logistics and the fourth logistics are as described in the first aspect of the present application.

[0225] According to a preferred embodiment, in step f) of the method of the second aspect of the present application, a fifth stream is further formed, wherein the fifth stream comprises 1,2-dichloropropane and 1,2,3-trichloropropane.

[0226] The method further comprises the following steps:

[0227] f) returning the fifth stream obtained in step e) to the second reaction device.

[0228] System for preparing tetrachloropropane and 1,2-dichloropropane from DD mixture

[0229] The third aspect of the present application relates to a system for operating the method for preparing tetrachloropropane and 1,2-dichloropropane from a DD mixture according to the first aspect of the present application, wherein the system comprises a first reaction device as a microchannel reactor, wherein:

[0230] The first reaction device is configured to have at least one inlet and at least one outlet;

[0231] At least one of the inlets of the first reaction device is configured to receive a first feed, the first feed comprising a DD mixture and chlorine gas, the DD mixture comprising 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene;

[0232] The first reaction apparatus is configured to react the first feed to form a first reaction mixture, the first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane;

[0233] At least one of the outlets of the first reaction device is configured to discharge the first reaction mixture.

[0234] The microchannel reactor, the first feed, and the first reaction mixture are as described in the first aspect of the present application.

[0235] According to a preferred embodiment, the system of the third aspect of the present application further comprises the following first purification device:

[0236] The first purification device comprises at least one inlet and at least one outlet, at least one of the inlets of the first purification device is configured to receive the first reaction mixture from the first reaction device, the first purification device is configured to purify the first reaction mixture to form a first stream and a second stream,

[0237] The first stream comprises 1,2-dichloropropane,

[0238] The second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane,

[0239] The first outlet of the first purification device is configured to discharge the first stream,

[0240] The second outlet of the first purification device is configured to discharge the second stream.

[0241] The first purification device in the third aspect of the present application is the same as or similar to the first purification device described in the first aspect of the present application.

[0242] The first logistics and the second logistics are as described in the first aspect of the present application.

[0243] According to a preferred embodiment, the system of the third aspect of the present application further comprises the following second reaction device:

[0244] The second reaction device is configured to include at least one inlet and at least one outlet, and the second reaction device is configured to receive the first stream from the first purification device through at least one of its inlets, and react the first stream to form the following third stream, wherein the third stream includes 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane, and optionally 1,2-dichloropropane and 1,2,3-trichloropropane.

[0245] The second reaction device in the third aspect of the present application is the same as or similar to the second reaction device described in the first aspect of the present application.

[0246] The third logistics is as described in the first aspect of the present application.

[0247] In a preferred embodiment, the system of the third aspect of the present application further comprises a second purification device:

[0248] The second purification device is configured to include at least one inlet and at least one outlet, and the second purification device is configured to receive the third stream from the second reaction device through at least one of its inlets and form the following fourth stream: the fourth stream includes 1,2-dichloropropane and 1,2,3-trichloropropane.

[0249] The second purification device can be any purification device well known to those skilled in the art, including but not limited to a distillation device, a rectification device or a combination thereof, as described in patent application CN112979413A, which is incorporated herein by reference in its entirety.

[0250] The fourth logistics described in the third aspect of the present application is as described in the first aspect of the present application.

[0251] According to a further preferred embodiment, in the system of the third aspect of the present application, the following fifth logistics is also formed in the second purification device: the fifth logistics contains 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0252] According to a further preferred embodiment, in the system of the third aspect of the present application, the following sixth logistics is also formed in the second purification device: the sixth logistics contains 1,1,2,2,3-pentachloropropane and 1,1,1,2,3-pentachloropropane.

[0253] The fifth logistics and the sixth logistics described in the third aspect of the present application are as described in the first aspect of the present application.

[0254] System for operating a process for preparing tetrachloropropene

[0255] The fourth aspect of the present application relates to a system for operating the method for preparing tetrachloropropylene as described in the second aspect of the present application, the system comprising a first reaction device as a microchannel reactor, a first purification device, and a third reaction device, wherein:

[0256] The first reaction device is configured to have at least one inlet and at least one outlet; at least one of the inlets of the first reaction device is configured to receive a first feed, the first feed comprises a DD mixture and chlorine gas, the DD mixture comprises 1,2-dichloropropane, 1,3-dichloropropene and 2,3-dichloropropene; the first reaction device is configured to react the first feed to form a first reaction mixture, the first reaction mixture comprises 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; at least one of the outlets of the first reaction device is configured to discharge the first reaction mixture;

[0257] The first purification device comprises at least one inlet and at least one outlet, at least one of the inlets of the first purification device is configured to receive the first reaction mixture from the first reaction device, the first purification device is configured to purify the first reaction mixture to form a first stream and a second stream, the first stream comprises 1,2-dichloropropane, the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane, the first outlet of the first purification device is configured to discharge the first stream, and the second outlet of the first purification device is configured to discharge the second stream;

[0258] The third reaction device comprises at least one inlet and at least one outlet, at least one of the inlets of the third reaction device is configured to receive the second stream from the first purification device and form tetrachloropropene.

[0259] According to a preferred embodiment, the system of the fourth aspect of the present application further comprises the following second reaction device:

[0260] The second reaction device is configured to include at least one inlet and at least one outlet, and the second reaction device is configured to receive the first stream from the first purification device through at least one of its inlets, and react the first stream to form the following third stream, wherein the third stream includes 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane, and optionally 1,2-dichloropropane and 1,2,3-trichloropropane.

[0261] According to a preferred embodiment, the system of the fourth aspect of the present application further comprises a second purification device:

[0262] The second purification device is configured to include at least one inlet and at least one outlet, and the second purification device is configured to receive the third stream from the second reaction device through at least one of its inlets and form the following fourth stream: the fourth stream includes 1,2-dichloropropane and 1,2,3-trichloropropane.

[0263] According to a preferred embodiment, in the system of the fourth aspect of the present application, the following fifth logistics is also formed in the second purification device: the fifth logistics contains 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

[0264] According to a further preferred embodiment, in the system of the fourth aspect of the present application, a sixth logistics is also formed in the second purification device, and the following sixth logistics is also formed in the second purification device: the sixth logistics contains 1,1,2,2,3-pentachloropropane and 1,1,1,2,3-pentachloropropane.

[0265] In a non-limiting example, the third reaction device in the system of the fourth aspect of the present application may include:

[0266] 1) A first dehydrochlorination unit, wherein

[0267] The first dehydrochlorination device comprises at least one inlet and at least one outlet; the first dehydrochlorination device is configured to receive the second stream from the first purification device via at least one of the inlets, and to receive the first phase transfer catalyst and the first liquid alkali via at least one of the inlets; in the first dehydrochlorination device, the second stream is subjected to a dehydrochlorination reaction to form a seventh stream comprising 1,2,3-trichloropropene, 1,1,3-trichloropropene and 2,3,3-trichloropropene, and the first dehydrochlorination device is configured to discharge the seventh stream via at least one of its outlets;

[0268] 2) a second chlorination reaction device, wherein the second chlorination reaction has at least one inlet and at least one outlet; the second chlorination reaction device is configured to receive the seventh stream from the first dehydrochlorination device through at least one of its inlets, and to receive chlorine gas through one of its inlets; in the second chlorination reaction device, the seventh stream is subjected to chlorination reaction to form an eighth stream, and the eighth stream contains tetrachloropropane and / or pentachloropropane; the second chlorination reaction device is configured to remove the eighth stream through one or more of its outlets;

[0269] 3) an optional third purification unit having at least one inlet and at least one outlet, the third purification unit being configured to receive an eighth stream from the second chlorination reaction unit via one or more of its inlets, the third purification unit being configured to form a tenth stream comprising primarily 1,2,2,3-tetrachloropropane, and a ninth stream comprising primarily 1,1,1,2,3-pentachloropropane and 1,1,2,2,3-pentachloropropane;

[0270] 4) a second dehydrochlorination device, the second dehydrochlorination device having at least one inlet and at least one outlet, the second dehydrochlorination device being configured to receive an eighth stream from the second chlorination reaction device or a ninth stream from the third purification device via one or more of its inlets, and the second dehydrochlorination device being configured to receive a second phase transfer catalyst and a second liquid alkali via one or more of its inlets; optionally, the second dehydrochlorination reaction device being configured to receive a sixth stream from the second purification device via one or more of its inlets; in the second dehydrochlorination reaction device, the eighth stream or the ninth stream is subjected to a dehydrochlorination reaction to form an eleventh stream mainly comprising 1,1,2,3-tetrachloropropene and 2,3,3,3-tetrachloropropene;

[0271] 5) an optional photocatalytic isomerization unit configured to receive the eleventh stream from the second dehydrochlorination unit via one or more of its inlets, the photocatalytic isomerization unit configured to convert the 2,3,3,3-tetrachloropropene in the eleventh stream into 1,1,2,3-tetrachloropropene.

[0272] Optionally, the first dehydrochlorination is further configured to receive, via one or more of its inlets, a tenth stream from the third purification unit as indicated.

[0273] In a preferred embodiment, the third reaction device in the system of the fourth aspect of the present application may be as described in patent application CN116444339A, which is incorporated into the present application in its entirety by reference.

[0274] The reaction devices, purification devices and logistics described in the fourth aspect of the present application are as described in the first and / or second aspect of the present application.

[0275] The present invention is further described below in conjunction with specific examples. It should be understood that the purpose of the following examples is only to illustrate the present application, and not to limit the present application in any way.

[0276] Example

[0277] The equipment, reactants and testing methods used in the examples of this application are as follows:

[0278] The microchannel reactor used was purchased from Jiangsu Ruiheng New Materials Co., Ltd. with the brand name ss-0010wr-ti-p.

[0279] DD mixture comes from Jiangsu Ruiheng New Materials Co., Ltd.

[0280] Hexamethylene-1-n-hexyldimethyl-6-octadecyldimethylammonium bromide was obtained from Shanghai MacLean Biochemical Technology Co., Ltd.

[0281] Sodium hydroxide: Jiangsu Runfeng Synthetic Technology Co., Ltd.

[0282] Hydrochloric acid: Jiangsu Ruiheng New Materials Co., Ltd.

[0283] Al powder: Shanghai Aladdin Reagent Co., Ltd.

[0284] The composition of each stream was detected by liquid chromatography.

[0285] Chromatography: Agilent Technologies China Co., Ltd. 8860GC

[0286] UV light source: CEL-LAM500 long arc mercury lamp source from Beijing Zhongjiao Jinyuan Technology Co., Ltd.

[0287] Examples 1a to 1c: Preparation of Tetrachloropropane and 1,2-Dichloropropane from DD Mixture

[0288] DD mixture raw materials (cis / trans-1,3-dichloropropylene ~ 35wt%, 2,3-dichloropropylene ~ 8wt%, 1,2-dichloropropane ~ 50wt%) and chlorine are sequentially introduced into the first module and the second module of the microchannel reactor for the first chlorination reaction. The reaction undergoes one stage (Example 1a), or two stages with different temperatures (Example 1b, Example 1c), and the total residence time of the material in the microchannel reactor is 60s. The molar ratio of chlorine to dichloropropylene is 1.03:1, and the tail gas is absorbed by the sodium hydroxide solution to obtain a first reaction mixture containing tetrachloropropane. The content of each component in the first reaction mixture is detected by gas chromatography, and the tetrachloropropane yield, dichloropropylene conversion rate, and 1,2-dichloropropane conversion rate are calculated.

[0289] Example 1d

[0290] Example 1a was repeated, except that the reaction went through two stages, the temperature of both stages was 60° C., and the residence time of each stage was 45 s (ie, the total residence time was extended from 60 s in Example 1a to 90 s).

[0291] Example 1e

[0292] Example 1a was repeated, except that the reaction went through 2 stages, the temperature of both stages was 60° C., the residence time of the first stage was 50 s, and the residence time of the second stage was 10 s.

[0293] Example 1g

[0294] Example 1b was repeated, except that the reaction temperature of the first stage was adjusted to 30°C.

[0295] Example 1h Effect of reaction temperature

[0296] Example 1b was repeated, except that the reaction temperature of the first stage was adjusted to 80°C.

[0297] Comparative Example 1-1

[0298] Example 1a was repeated, except that a conventional reactor was used instead of a microchannel reactor to carry out the chlorination reaction of the DD mixture. Specifically, 1000 g of the DD mixture was added to a 1L four-necked bottle with a thermometer and a stirrer, the initial chlorine flow rate was 15 L / h, the reaction temperature was 60°C, the reaction was protected from light, the reaction tail gas was discharged into a fume hood through secondary absorption, and the reaction liquid was tested for residual chlorine, weight, and GC normalized data after the reaction.

[0299] The results obtained in Examples 1a to 1h and Comparative Example 1 are shown in Table 1.

[0300] Table 1:

[0301]

[0302] It can be seen from the results in Table Example 1a and Comparative Example 1-1 that the present application significantly suppresses the conversion rate of 1,2-dichloropropane in the DD mixture (only 0.7%) by using a microchannel reactor, thereby achieving the technical effect of suppressing the reaction of specific raw materials.

[0303] At the same time, the results in Example 1a and Comparative Example 1-1 show that the use of a microchannel reactor significantly improves the tetrachloropropane yield and the conversion rate of dichloropropylene. For example, using a conventional reactor, the undesired 1,2-dichloropropane conversion rate reaches 3.5%, which is significantly higher than Example 1a (0.7%); in addition, the tetrachloropropane yield and dichloropropylene conversion rate in Comparative Example 1-1 using a conventional reactor (78% and 88%, respectively) are significantly lower than the tetrachloropropane yield and dichloropropylene conversion rate in Example 1a (93% and 99%, respectively).

[0304] In addition, the present application further improves the technical effect by controlling the total residence time, residence time distribution and temperature of each stage in the microchannel reactor.

[0305] For example, as can be seen from the comparison between Example 1a and Example 1d, using a longer total residence time in the microchannel reactor further reduces the undesirable 1,2-dichloropropane conversion rate (from 0.7% in Example 1a to 0.42% in Comparative Example 1-2), while the tetrachloropropane yield and the dichloropropane conversion rate are not significantly affected.

[0306] For another example, from the comparison between Example 1a and Example 1e, it can be seen that, under the same reaction temperature, the use of a two-stage reaction can further reduce the undesirable 1,2-dichloropropane conversion rate (from 0.7% in Example 1a to 0.33% in Comparative Examples 1-3), while the tetrachloropropane yield and the dichloropropane conversion rate are not significantly affected.

[0307] Comparison between Example 1f and Example 1b shows that, in the case of a two-stage reaction, lowering the reaction temperature of the first stage helps to further suppress the conversion rate of 1,2-dichloropropane (the conversion rate of 1,2-dichloropropane is reduced from 0.3% in Example 1b to 0.03% in Example 1f), thereby better achieving the goal of not reacting 1,2-dichloropropane in the raw material DD mixture but reacting dichloropropylene.

[0308] Example 2: Synthesis of tetrachloropropane and pentachloropropane mixed product by two-pot continuous chlorination reaction of 1,2-dichloropropane

[0309] The reaction mixture from Example 1-a was distilled and separated. The distillation separation was carried out in the following first distillation column:

[0310] The distillation tower is 60 cm high, the packing is θ ring, the height is 50 cm, there are about 10 to 12 theoretical plates, the distillation pressure is negative pressure -0.04Mpa, the reflux ratio is 3:1, the tower bottom temperature is 88 to 100°C, and the tower top temperature is 50 to 70°C. The purity of 1,2-dichloropropane in the obtained first stream reaches more than 98.5%, and the second stream is obtained at the bottom of the tower, the main components of which are tetrachloropropane, pentachloropropane and heavy components.

[0311] Subsequently, 300 g of 1,2-dichloropropane obtained by distillation separation was added into a 500 mL four-necked round-bottom flask (first kettle) equipped with a condenser, a thermometer, a stirrer, and a gas guide tube, with a chlorine gas flow rate of 20 L / h.

[0312] Aluminum powder was used as a catalyst in the first kettle (feeding amount: 0.1% of the mass of 1,2-dichloropropane). The reaction was carried out for 6 hours by irradiation with a 50W ultraviolet lamp with a wavelength of 253nm. The tail gas was absorbed by alkali solution and the chlorination condition in the kettle was monitored by GC normalization.

[0313] The reaction solution was pumped into the second kettle, and 0.1% aluminum powder was added, with a chlorine gas flow rate of 30 L / h, and the reaction was further irradiated with an ultraviolet lamp for 6 hours.

[0314] The product obtained in the second reactor is collected and put into the second distillation tower, which is 60 cm high, filled with θ rings, 50 cm high, about 10 to 12 theoretical plates, negative pressure -0.06Mpa, reflux ratio of 3:1, tower bottom temperature of 104 to 126°C, and tower top temperature of 72 to 80°C. The fifth stream is obtained at the top of the tower, in which the mass fraction of 1,2-dichloropropane is about 24% and the mass fraction of 1,2,3-trichloropropane is 75%; the fourth stream, whose main components are tetrachloropropane, pentachloropropane and heavy components, is obtained at the bottom of the tower.

[0315] Comparative Example 2-1

[0316] Example 2a was repeated, except that the time of the chlorination reaction in the first kettle was set to 9 hours.

[0317] Comparative Example 2-2

[0318] Example 2a was repeated, except that the chlorination reaction time in the second kettle was set to 9 hours.

[0319] Comparative Examples 2-3

[0320] Example 2a was repeated except that the temperature of the chlorination reaction in the first kettle was set to 40°C.

[0321] The reaction conditions used in Examples 2a to 2b and Comparative Examples 2-1 to 2-4, the 1,2-dichloropropane conversion, 1,2,3-trichloropropane selectivity and tetrachloropropane selectivity in the first kettle, and the 1,2,3-trichloropropane conversion, tetrachloropropane selectivity and pentachloropropane selectivity in the second kettle are summarized in the following Table 2:

[0322] Table 2

[0323]

[0324] Examples 2a and 2b show that by using Al powder as a catalyst and UV irradiation conditions, a continuous chlorination reaction of 1,2-dichloropropane is achieved at low temperature, so that 1,2-dichloropropane is highly selectively converted into tetrachloropropane via highly selective conversion into 1,2,3-trichloropropane.

[0325] The results in Comparative Examples 2-1 and 2-2 respectively show the effect of the reaction time of the first kettle chlorination on the selectivity of 1,2,3-trichloropropane, and the effect of the reaction time of the second kettle chlorination on the selectivity of tetrachloropropane. The result of Comparative Example 2-1 shows that extending the reaction time of the first kettle chlorination reduces the selectivity of 1,2,3-trichloropropane; the result of Comparative Example 2-2 shows that extending the reaction time of the second kettle chlorination reduces the selectivity of tetrachloropropane and increases the selectivity of pentachloropropane.

[0326] The results in Comparative Examples 2-3 show the effect of the reaction temperature of the first kettle chlorination on the selectivity of 1,2,3-trichloropropane. Using a higher first kettle chlorination temperature (and this temperature is higher than the second kettle chlorination temperature) reduces the selectivity of the desired product 1,2,3-trichloropropane.

[0327] Example 3

[0328] (1) The first dehydrochlorination reaction:

[0329] Combine the second stream and the fourth stream obtained in Example 2a, and take 300g as the raw material. Mix the first phase transfer catalyst (hexamethylene-1-n-hexyldimethyl-6-octadecyldimethylammonium bromide) and the raw material in a mass ratio of 2:1000, place in a kettle reactor, heat to 65°C and then drop a 15% by weight sodium hydroxide solution, the molar ratio of the amount of sodium hydroxide to the tetrachloropropane in the raw material is 1.03:1. The obtained reaction solution is adjusted to a neutral pH (pH of 7.1) by hydrochloric acid (concentration 20% by weight) and finely separated to obtain the seventh stream containing trichloropropene in the oil phase.

[0330] (2) Second Chlorination Reaction

[0331] The seventh logistics and chlorine are sequentially introduced into the first module and the second module of the microchannel reactor for the first stage and the second stage of the second chlorination reaction respectively. The temperature of the first stage is 40° C., the residence time is 55 s, and the temperature of the second stage is 65° C., and the residence time is 20 s. The molar ratio of chlorine to the seventh logistics is 1.04:1. The tail gas is absorbed by sodium hydroxide solution to obtain the eighth logistics.

[0332] (3) Second dehydrochlorination reaction

[0333] The second phase transfer catalyst (hexamethylene-1-n-hexyldimethyl-6-octadecyldimethylammonium bromide) and the eighth stream were mixed in a tank reactor at a mass ratio of 4:1000, heated to 55°C, and then a 15 wt% sodium hydroxide solution was added, and the molar ratio of the amount of sodium hydroxide to the eighth stream was 1.03:1. The obtained reaction solution was adjusted to pH 7.1 by hydrochloric acid to obtain the eleventh stream.

[0334] (4) Photocatalytic isomerization

[0335] Nano titanium tetrachloride (average particle size 200 nm) and the tenth stream are sequentially introduced into the first module and the second module of the microchannel reactor at a mass ratio of 1.3:1000, and subjected to the first stage and the second stage of photocatalytic isomerization reaction. The temperature of the first stage is 80° C., the light source is a 25W LED light source with a wavelength of 450 nm, and the residence time is 35 seconds to obtain 1,1,2,3-tetrachloropropene.

[0336] The total conversion rate of 1,2-dichloropropane and 1,3-dichloropropylene and 2,3-dichloropropylene in the DD mixture into 1,1,2,3-tetrachloropropylene is shown in the following table:

[0337] name 1,2-Dichloropropane 1,3-Dichloropropylene 2,3-Dichloropropylene Total conversion rate % 88.9 98.9 99.0

[0338] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing tetrachloropropane and 1,2-dichloropropane from a DD mixture, the method comprising the following steps: a) allowing a first feed to enter the first reaction device through an inlet of the first reaction device, wherein: The first feed comprises DD mixture and chlorine, The first reaction device is a microchannel reactor, and The DD mixture contains 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene; b) reacting the first feed in the first reaction unit to form a first reaction mixture, the first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; Preferably: - the content of 1,2-dichloropropane in the DD mixture is 40 to 75% by weight, based on the total weight of the DD mixture; and / or - the content of dichloropropylene in the DD mixture is 25 to 60% by weight, based on the total weight of the DD mixture; and / or - the content of 1,3-dichloropropylene in the DD mixture is 20 to 50% by weight, based on the total weight of the DD mixture; and / or - the content of cis-1,3-dichloropropene in the DD mixture is 10 to 25% by weight, based on the total weight of the DD mixture; and / or - the content of trans-1,3-dichloropropene in the DD mixture is 10 to 25% by weight, based on the total weight of the DD mixture; and / or - the content of 2,3-dichloropropylene in the DD mixture is 5 to 10% by weight, based on the total weight of the DD mixture; and / or - the DD mixture further comprises allyl chloride, wherein the content of allyl chloride is 0 to 10 wt %, based on the total mass of the DD mixture; and / or - In step a), the mass flow rate of the DD mixture is 0.1 to 100 g / min; and / or - in step a), the mass flow rate of chlorine gas may be 0.1 to 20 g / min; and / or - in step b), the reaction temperature is 15 to 100°C; and / or - in step b), the total residence time is from 10 to 300 seconds; and / or - in step b), the total residence time is from 10 to 300 seconds, or from 10 to 120 seconds, or from 30 to 90 seconds; and / or The molar ratio of tetrachloropropane to dichloropropylene is at least 1000, or at least 2000, or at least 5000, or at least 10000.

2. The method according to claim 1, wherein the microchannel reactor has 1 to 5 stages; Preferably, the microchannel reactor has more than 1 stage, and the temperature of the nth stage of the microchannel is greater than or equal to the temperature of the n-1th stage; Preferably, the microchannel reactor has two stages, and step b) is carried out as follows: in the first stage of the microchannel reactor, the reaction is carried out at temperature T1, and the residence time in the first stage is t1, and then in the second stage of the microchannel reactor, the reaction is carried out at temperature T2, and the residence time in the second stage is t2. Preferably: T1 is 30 to 60°C, or 35 to 55°C, or 40 to 50°C; and / or T2 is 40 to 70°C, or 45 to 65°C, or 50 to 60°C, provided that the temperature of the second stage is higher than the temperature of the first stage.

3. The method according to claim 1, wherein: The method further comprises the following steps: c) passing the first reaction mixture into a first purification unit to form a first stream and a second stream, wherein the first stream comprises 1,2-dichloropropane and the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; Preferably step c) has one or more of the following characteristics: 1) The content of 1,2-dichloropropane in the first stream is at least 50% by weight; and / or 2) in the second stream, the mass fraction of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane is at least 50 wt %; Preferably, the method further comprises the following steps: d) passing the first stream obtained in step c) into a second reaction device to obtain a third stream comprising 1,2-dichloropropane, 1,2,3-trichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; Preferably step d) has one or more of the following characteristics: 1) The temperature in the second reaction device is -30 to 30°C; and / or 2) The total reaction time in the second reaction device is 1 to 30 hours, or 1 to 20 hours; and / or 3) The second reaction device comprises 1 to 5 stages; and / or 4) The second reaction device has 2 or more stages, and the temperature of the nth stage is greater than or equal to the reaction temperature of the n-1th stage; More preferably, the second reaction device has 2 or more stages, wherein the reaction time of the nth stage is greater than or equal to the reaction time of the n-1th stage; More preferably, the second reaction device has 2 stages, and the step d) is carried out by: allowing the first stream obtained in step c) to enter the second reaction device, reacting at temperature T3 for t3 in the first stage, and then reacting at temperature T4 for time t4 in the second stage; Preferably T3 is -30 to 0°C, or -20 to 0°C, or -15 to -5°C; and / or T4 is -5 to 20°C, or -5 to 15°C, or -5 to 10°C, or -5 to 5°C; and / or t3 is 1 to 16 hours, or 2 to 14 hours, or 4 to 12 hours; and / or t4 is 1 to 16 hours, or 2 to 14 hours, or 4 to 12 hours; and / or 5) the equivalent ratio of the first stream and chlorine entering the second reaction device is 1:0.5 to 1:1.5; and / or 6) the molar content of pentachloropropane in the third stream is no more than 20 mole %, relative to the total molar content of halogenated propane in the third stream; and / or 7) the molar content of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane in the third stream is at least 50 mole %, relative to the total molar content of the halogenated propane in the third stream; Preferably, the method further comprises the following steps: e) passing the third stream obtained in step d) into a second purification device to form a fourth stream, wherein the fourth stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; Preferably step e) has one or more of the following characteristics: 1) in the fourth stream, the mass fraction of 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane is at least 50 wt %, relative to the total mass of the fourth stream; and / or 2) in step e), a fifth stream is also formed, the fifth stream comprising 1,2-dichloropropane and 1,2,3-trichloropropane; preferably, the mass fraction of 1,2-dichloropropane and 1,2,3-trichloropropane in the fifth stream is at least 50 wt%; and / or 3) in step e), a sixth stream is also formed, the sixth stream comprising 1,1,2,2,3-pentachloropropane and 1,1,1,2,3-pentachloropropane; preferably, the mass fraction of 1,1,2,2,3-pentachloropropane and 1,1,1,2,3-pentachloropropane in the sixth stream is at least 50 wt %; Preferably, the method further comprises the following steps: f) returning the fifth stream obtained in step e) to the second reaction device.

4. A method for preparing tetrachloropropylene, the method comprising the following steps: a) allowing a first feed to enter the first reaction device through an inlet of the first reaction device, wherein: The first feed comprises DD mixture and chlorine, The first reaction device is a microchannel reactor, and The DD mixture contains 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene; b) reacting the first feed in the first reaction unit to form a first reaction mixture, the first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; c) passing the first reaction mixture into a first purification unit to form a first stream and a second stream, wherein the first stream comprises 1,2-dichloropropane and the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; and d) obtaining tetrachloropropene from the second stream. Preferably, the method comprises the following steps: e) passing the first stream obtained in step c) into a second reaction device to obtain a third stream comprising 1,2-dichloropropane, 1,2,3-trichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; Preferably, the method further comprises the following steps: f) allowing the third stream obtained in step e) to enter a second purification device to form a fourth stream, wherein the fourth stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; preferably, a fifth stream is further formed in step f), wherein the fifth stream comprises 1,2-dichloropropane and 1,2,3-trichloropropane; Preferably, the method further comprises the following steps: g) returning the fifth stream obtained in step f) to the second reaction device.

5. A system for operating the process for preparing tetrachloropropane and 1,2-dichloropropane from a DD mixture according to any one of claims 1 to 3, the system comprising a first reaction device as a microchannel reactor, wherein: The first reaction device is configured to have at least one inlet and at least one outlet; At least one of the inlets of the first reaction device is configured to receive a first feed, the first feed comprising a DD mixture and chlorine gas, the DD mixture comprising 1,2-dichloropropane, 1,3-dichloropropylene and 2,3-dichloropropylene; The first reaction apparatus is configured to react the first feed to form a first reaction mixture, the first reaction mixture comprising 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; At least one of the outlets of the first reaction device is configured to discharge the first reaction mixture; Preferably, the system further comprises the following first purification device: The first purification device comprises at least one inlet and at least one outlet, at least one of the inlets of the first purification device is configured to receive the first reaction mixture from the first reaction device, the first purification device is configured to purify the first reaction mixture to form a first stream and a second stream, The first stream comprises 1,2-dichloropropane, The second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane, The first outlet of the first purification device is configured to discharge the first stream, The second outlet of the first purification device is configured to discharge the second stream. Preferably, the system further comprises the following second reaction device: The second reaction device is configured to include at least one inlet and at least one outlet, the second reaction device is configured to receive the first stream from the first purification device via at least one of its inlets, and react the first stream to form a third stream comprising 1,2-dichloropropane, 1,2,3-trichloropropane, and 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; Preferably, the system further comprises a second purification device: The second purification device is configured to include at least one inlet and at least one outlet, and the second purification device is configured to receive the third stream from the second reaction device via at least one of its inlets and form the following fourth stream: the fourth stream includes 1,2-dichloropropane and 1,2,3-trichloropropane; Preferably, the second purification device further forms the following fifth stream, wherein the fifth stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

6. A system for operating the method for preparing tetrachloropropene as claimed in claim 4, said system comprising a first reaction device as a microchannel reactor, a first purification device, and a third reaction device, wherein: The first reaction device is configured to have at least one inlet and at least one outlet; at least one of the inlets of the first reaction device is configured to receive a first feed, the first feed comprises a DD mixture and chlorine gas, the DD mixture comprises 1,2-dichloropropane, 1,3-dichloropropene and 2,3-dichloropropene; the first reaction device is configured to react the first feed to form a first reaction mixture, the first reaction mixture comprises 1,2-dichloropropane, 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; at least one of the outlets of the first reaction device is configured to discharge the first reaction mixture; The first purification device comprises at least one inlet and at least one outlet, at least one of the inlets of the first purification device is configured to receive the first reaction mixture from the first reaction device, the first purification device is configured to purify the first reaction mixture to form a first stream and a second stream, the first stream comprises 1,2-dichloropropane, the second stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane, the first outlet of the first purification device is configured to discharge the first stream, and the second outlet of the first purification device is configured to discharge the second stream; The third reaction device comprises at least one inlet and at least one outlet, at least one of the inlets of the third reaction device is configured to receive the second stream from the first purification device and form tetrachloropropene; Preferably, the system further comprises the following second reaction device: The second reaction device is configured to include at least one inlet and at least one outlet, the second reaction device is configured to receive the first stream from the first purification device via at least one of its inlets, and react the first stream to form a third stream comprising 1,2-dichloropropane, 1,2,3-trichloropropane, and 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane; Preferably, the system further comprises a second purification device: The second purification device is configured to include at least one inlet and at least one outlet, and the second purification device is configured to receive the third stream from the second reaction device via at least one of its inlets and form the following fourth stream: the fourth stream includes 1,2-dichloropropane and 1,2,3-trichloropropane; Preferably, the second purification device further forms the following fifth stream: the fifth stream comprises 1,1,2,3-tetrachloropropane and 1,2,2,3-tetrachloropropane.

7. A composition comprising tetrachloropropane and 1,2-dichloropropane prepared by the process according to any one of claims 1 to 3.

8. A tetrachloropropene product obtained by the process according to claim 4.

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