Method for resource utilization of 1, 1, 2-trichloropropane
By converting 1,1,2-trichloropropane into 1,1,2,3-tetrachloropropene through high-temperature cracking and chlorination, the problems of low reaction efficiency and poor product selectivity in existing technologies are solved, realizing the efficient resource utilization and economic benefits of 1,1,2-trichloropropane.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-29
- Publication Date
- 2026-04-07
AI Technical Summary
Existing methods for treating 1,1,2-trichloropropane suffer from problems such as low reaction efficiency, poor product selectivity, and high catalyst costs, making it impossible to effectively utilize the resources.
1,1,2-trichloropropane is converted to 3,3-dichloropropene using a high-temperature pyrolysis process, and then chlorinated to obtain 1,1,2,3-tetrachloropropane. Further pyrolysis, chlorination and dehydrochlorination are then used to obtain 1,1,2,3-tetrachloropropene. The high-temperature pyrolysis fixed-bed reaction process avoids catalyst deactivation and coking, and the reaction temperature and residence time are precisely controlled.
This has enabled the efficient resource utilization of 1,1,2-trichloropropane, reduced residue disposal and overall production costs, improved reaction efficiency and selectivity, and established a sound circular economy model.
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of chemical synthesis, in particular to a method for resource utilization of 1,1,2-trichloropropane. BACKGROUND
[0002] In the field of modern agriculture and chemical industry, 1,3-dichloropropene shows many application values: as a soil fumigant, it can be used in combination with chloropicrin to effectively control root-knot nematodes, short-bodied nematodes and other nematodes and underground pests; at the same time, it also plays a key role in the fields of chemical reagents, solvents, organic synthesis, antifungal agents and pharmaceutical intermediates. 1,3-dichloropropene can be generated by high-temperature chlorination of propylene and chloropropylene, but by-products 1,1,2-trichloropropane will be generated during the chlorination of propylene or chloropropylene. The traditional treatment method of 1,1,2-trichloropropane (e.g., incineration or landfill) not only causes resource waste, but also poses environmental risks. At present, although there are conversion methods to treat 1,1,2-trichloropropane, there are problems such as low reaction efficiency, poor product selectivity, and high catalyst cost, which cannot resource utilize 1,1,2-trichloropropane.
[0003] Therefore, it is urgent to provide a new method for resource utilization of 1,1,2-trichloropropane, which can efficiently and economically resource utilize 1,1,2-trichloropropane and promote the green development and resource recycling of the industry. SUMMARY
[0004] The purpose of the example embodiments of the present application is to solve the problems existing in the prior art. In view of the problems of low reaction efficiency, poor product selectivity, and high catalyst cost existing in the traditional conversion method, the inventors innovatively use 1,1,2-trichloropropane as raw material, convert it into 3,3-dichloropropene by high-temperature cracking process, and then obtain 1,1,2,3-tetrachloropropane by chlorination, and optionally further obtain 1,1,2,3-tetrachloropropene by cracking, chlorination and dehydrochlorination. The method described in the present application can realize the resource utilization of by-products on the one hand, reduce the residue disposal and overall production cost, improve the economic benefit, and build a good circular economy mode; on the other hand, it also avoids the risk of catalyst deactivation and coking by using high-temperature cracking fixed bed reaction process, accurately regulates the reaction temperature and residence time, effectively inhibits the occurrence of side reactions, and improves the reaction efficiency (conversion rate) and reaction selectivity.
[0005] In one aspect, the present application provides a method for resource utilization of 1,1,2-trichloropropane, which comprises: (1) high-temperature cracking of a material stream containing 1,1,2-trichloropropane to obtain a material stream containing 3,3-dichloropropene; (2) chlorinating the material stream containing 3,3-dichloropropene to obtain a material stream containing 1,1,2,3-tetrachloropropane. In the present application, the method of resource utilization of 1,1,2-trichloropropane can pyrolyze the propylene chlorination by-product 1,1,2-trichloropropane into 3,3-dichloropropene, and then obtain 1,1,2,3-tetrachloropropane after chlorination. This fundamentally solves the by-product 1,1,2-trichloropropane, and the process route is simple, the flow is short, the reaction conversion rate is high, the selectivity is good, and it is conducive to industrial implementation.
[0006] In an embodiment of the present application, the method further comprises: (3) pyrolyzing the material stream containing 1,1,2,3-tetrachloropropane to obtain a material stream containing 1,2,3-trichloro-1-propene; (4) chlorinating the material stream containing 1,2,3-trichloro-1-propene to obtain a material stream containing 1,1,2,2,3-pentachloropropane; (5) dehydrochlorinating the material stream containing 1,1,2,2,3-pentachloropropane to obtain a material stream containing 1,1,2,3-tetrachloropropene.
[0007] In the present application, the method of resource utilization of 1,1,2-trichloropropane can further pyrolyze, chlorinate and dehydrochlorinate 1,1,2,3-tetrachloropropane to generate 1,1,2,3-tetrachloropropene. This also fundamentally solves the by-product 1,1,2-trichloropropane, and its process route is simple, economical, high reaction conversion rate, good selectivity, and conducive to industrial implementation.
[0008] In an embodiment of the present application, the pyrolysis in step (1) is carried out without carrier gas, or in the presence of at least one inert gas selected from nitrogen, argon, helium, carbon dioxide.
[0009] In an embodiment of the present application, the pyrolysis in step (1) is carried out under the following conditions: preheating temperature 100-200°C, reaction temperature 350-600°C, space velocity 10-500h -1 , pressure 0-2MPa.
[0010] In an embodiment of the present application, step (1) further comprises rectifying the material stream containing 3,3-dichloropropene.
[0011] In an embodiment of the present application, the chlorination in step (2) is carried out under the following conditions: preheating temperature 50-100°C, reaction temperature 50-150°C, space velocity 100-500h -1 , pressure 0-1MPa, feed flow rate 0.5-2ml / min, chlorine flow rate 50-200ml / min.
[0012] In one embodiment of the present invention, the conditions for high-temperature pyrolysis in step (3) include: preheating temperature 50-100℃, reaction temperature 350-600℃, and space velocity 10-500 h⁻¹. -1 Pressure 0-2MPa.
[0013] In one embodiment of the present invention, the chlorination in step (4) is carried out under the following conditions: preheating temperature 50-100°C, reaction temperature 80-200°C, and space velocity 10-500 h⁻¹. -1 Pressure 0-1 MPa, chlorine flow rate 50-200 ml / min.
[0014] In one embodiment of the present invention, the dehydrochlorination in step (5) is carried out in the presence of a phase transfer catalyst and a base, wherein the phase transfer catalyst is selected from one or more of hexadecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, and tetradecyldimethylbenzylammonium chloride.
[0015] In one embodiment of the present invention, in step (5), the mass ratio of phase transfer catalyst to 1,1,2,2,3-pentachloropropane is (0.002-0.01):1, the molar ratio of base to 1,1,2,2,3-pentachloropropane is (1-1.1):1, the reaction temperature is 70-90℃, the dropping time is 1-4h, and the holding time is 1-6h (hours).
[0016] Other features and aspects will become clear from the following detailed description and the claims. Detailed Implementation
[0017] Unless otherwise defined, the technical or scientific terms used in the claims and description shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.
[0018] In this document, the term “about” used to modify, for example, the amount, concentration, process temperature, process time, flow rate, and similar values and ranges of an ingredient in a composition, or the scale and similar values and ranges of a component, refers to possible changes in numerical values, such as those arising from routine measurements and operations used in the manufacture or use of formulations for preparing materials, compositions, complexes, concentrates, components, articles; accidental errors in these processes; differences in the purity or composition of the manufacturing, source, or starting materials used to carry out the method; and similar factors.
[0019] In this document, when a numerical range such as 5-25 is given, this means at least 5 or not less than 5 and separately and independently not greater than or less than 25. In some embodiments, such a range may be independently defined as not less than 5 and separately and independently not greater than 25. Values having such a range, such as 10, -15, or 10-20, also include the lower and upper limits of the range separately and independently in the same manner.
[0020] As used herein, unless otherwise specified, “% by weight” or “percentage by weight” for a component refers to the total weight of the composition or article containing that component. Terms such as “comprising” or “including” indicate that the elements or articles preceding “comprising” or “including” encompass the elements or articles listed following “comprising” or “including” and their equivalents, and do not exclude other elements or articles.
[0021] In this invention, the terms "high-temperature cracking" and "dehydrochlorination" are used interchangeably when referring to the same type of reaction, namely, a reaction that typically results in the formation of double bonds by removing hydrogen and chlorine atoms from adjacent carbon atoms in a chlorinated hydrocarbon reactant.
[0022] Unless otherwise stated, the (high-temperature) cracking, chlorination, distillation, dehydrochlorination, and other steps described in this invention can be performed using conventional apparatus, equipment, process conditions, etc., used in the art for their respective purposes. The reaction conditions that can be optimized by the methods described in this invention include any reaction conditions that are easily adjustable, for example, by using equipment and / or materials already present in the manufacturing footprint, or by achieving them at low resource costs. Examples of such conditions may include, but are not limited to, adjustments to temperature, pressure, flow rate, reactant molar ratio, etc. That is, the specific conditions used in each step described herein are not critical and are readily determined by those skilled in the art.
[0023] In this invention, the term "inert gas" refers to inert gases in a broad sense, including gases with strong intramolecular chemical bonds that are not easily reacted at room temperature and are often used as protective gases, such as rare gases, nitrogen, and carbon dioxide.
[0024] The method for resource utilization of 1,1,2-trichloropropane according to the present invention includes using 1,1,2-trichloropropane as raw material, and subjecting it to high-temperature cracking to obtain crude 3,3-dichloropropene. In some embodiments, the crude 3,3-dichloropropene is further separated by distillation to obtain 3,3-dichloropropene with a purity of 95% or higher, 99% or higher, or 99.95% or higher. The 3,3-dichloropropene is then chlorinated to obtain 1,1,2,3-tetrachloropropane. Optionally, the 1,1,2,3-tetrachloropropane is further cracked, chlorinated, and dehydrochlorinated to obtain 1,1,2,3-tetrachloropropene.
[0025] In this invention, the chlorination step may not require a catalyst, but may be used if necessary to enhance reaction kinetics. For example, a radical catalyst or initiator may be used to enhance the chlorination step. Such catalysts typically contain one or more chlorine, peroxide, or azo-(-N=N-R') groups and / or exhibit reactor phase fluidity / activity.
[0026] In some embodiments, the high-temperature pyrolysis reaction may be carried out without a carrier gas or using one or more inert gases such as nitrogen, argon, helium, and carbon dioxide. In some embodiments, the high-temperature pyrolysis reaction may be carried out under conventional conditions known in the art for this purpose, without particular limitations; for example, a process preheating temperature of 100-200°C, a reaction temperature of 350-600°C, and a space velocity of 10-500 h⁻¹. -1 Pressure 0-2MPa.
[0027] In some embodiments, the (light-light) distillation can be carried out under conventional conditions known in the art for this purpose, without particular limitations; for example, 10-60 process trays, bottom temperature 75-85°C, top temperature 30-40°C, vacuum pressure -0.1 to 0.05 MPa, and reflux ratio 1:0.5-5.
[0028] In some embodiments, the chlorination of 3,3-dichloropropene to 1,1,2,3-tetrachloropropane can be carried out under conventional conditions known in the art for this purpose, without particular limitations; for example, a process preheating temperature of 50-100°C, a reaction temperature of 50-150°C, and a space velocity of 100-500 h⁻¹. -1 Pressure 0-1MPa, feed flow rate 0.5-2 ml / min, chlorine flow rate 50-200 ml / min.
[0029] In some embodiments, the high-temperature pyrolysis of 1,1,2,3-tetrachloropropane to obtain 1,2,3-trichloro-1-propene can be carried out under conventional conditions known in the art for this purpose, without particular limitations; for example, a process preheating temperature of 50-150°C, a reaction temperature of 350-600°C, and a space velocity of 10-500 h⁻¹. -1 Pressure 0-2MPa.
[0030] In some embodiments, the chlorination of 1,2,3-trichloro-1-propene to obtain 1,1,2,2,3-pentachloropropane can be carried out under conventional conditions known in the art for this purpose, without particular limitations; for example, a process preheating temperature of 50-100°C, a reaction temperature of 80-200°C, and a space velocity of 10-500 h⁻¹. -1 Pressure 0-2MPa, chlorine flow rate 50-200 ml / min.
[0031] In some embodiments, the dehydrochlorination reaction of 1,1,2,2,3-pentachloropropane can be carried out in the presence of a base and / or a phase transfer catalyst. In this invention, the base is any base known in the art that can be used for this purpose. Suitable (cracking) bases include, but are not limited to, alkali metal hydroxides, such as sodium hydroxide, potassium hydroxide, and calcium hydroxide; alkali metal carbonates, such as sodium carbonate, lithium carbonate, rubidium carbonate, and cesium carbonate, or combinations thereof. In some embodiments, the molar ratio of base to 1,1,2,2,3-pentachloropropane is (1-1.1):1, (1-1.05):1, or (1-1.03):1.
[0032] In this invention, the phase transfer catalyst comprises quaternary ammonium and quaternary phosphonium salts to improve the dehydrochlorination reaction rate using a base. The phase transfer catalyst can be one or more of hexadecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, and tetradecyldimethylbenzylammonium chloride. In some embodiments, the mass ratio of the phase transfer catalyst to 1,1,2,2,3-pentachloropropane is (0.002-0.01):1, (0.004-0.008):1, or (0.005-0.007):1.
[0033] The dehydrochlorination reaction of 1,1,2,2,3-pentachloropropane can be carried out under conventional conditions known in the art for this purpose, without particular limitations; for example, a reaction temperature of 70-90°C, a dropping time of 1-4 h, and a holding time of 1-6 h.
[0034] Example
[0035] To make the technical solution and effects of the present invention clearer, the technical solution of the present invention will be further described below in conjunction with some specific embodiments. The described embodiments are for further illustrating the present invention and should not be construed as limiting the scope of protection of the present invention.
[0036] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.
[0037] Example 1: Preparation of 1,1,2,3-tetrachloropropane from 1,1,2-trichloropropane
[0038] 1,1,2-trichloropropane was transported at a space velocity of 150 h⁻¹ -1The material is pumped into a preheater at 150°C, and then flows into a fixed-bed reactor for pyrolysis at 550°C. The reaction liquid is recovered through a two-stage condensation system, and the tail gas is treated by water absorption, producing hydrochloric acid as a byproduct. Measurements showed that the conversion rate of 1,1,2-trichloropropane reached 90.21%; the main product was 3,3-dichloropropene with a selectivity of 93.45%, and the byproduct 1,1-dichloropropene had a selectivity of 5.47%.
[0039] The pyrolysis reaction solution was subjected to distillation, with the distillation column having 30 trays, a final reboiler temperature of 78-80℃, a vapor phase temperature of 45-50℃, a reflux ratio of 5:1, and a pressure of -0.05 MPa. Measurements showed that the normalized content of 3,3-dichloropropene was 99.97%.
[0040] High-purity 3,3-dichloropropene is chlorinated to obtain 1,1,2,3-tetrachloropropane: under normal pressure, preheating temperature 50℃, reaction temperature 80℃, and space velocity 80h⁻¹. -1 The chlorine flow rate was 50 mL / min. Measurements showed that the conversion rate of 3,3-dichloropropene was 99.94%, and the selectivity for the product 1,1,2,3-tetrachloropropane was 99.56%.
[0041] Example 2: Preparation of 1,1,2,3-tetrachloropropene from 1,1,2,3-tetrachloropropane
[0042] 1,1,2,3-Tetrachloropropane was transported at a space velocity of 150 h⁻¹ -1 The material is pumped into a preheater at 120°C, and then flows into a fixed-bed reactor for pyrolysis at 500°C. The reaction liquid is recovered through a two-stage condensation system, and the tail gas is treated by water absorption, producing hydrochloric acid as a byproduct. Measurements showed that the conversion rate of 1,1,2,3-tetrachloropropane reached 94.15%, and the selectivity for the product 1,2,3-trichloropropene was 95.46%.
[0043] 1,2,3-Trichloropropene is then chlorinated to obtain 1,1,2,2,3-pentachloropropane: under normal pressure, preheating temperature 50℃, reaction temperature 100℃, and space velocity 50h⁻¹. -1 The chlorine flow rate was 80 mL / min. Measurements showed that the conversion rate of 1,2,3-trichloropropene was 99.87%, and the selectivity for 1,1,2,2,3-pentachloropropane was 99.56%.
[0044] 1,1,2,2,3-Pentachloropropane was dehydrochlorinated to obtain 1,1,2,3-Tetrachloropropene. The phase transfer catalyst was hexadecyltrimethylammonium chloride, and the base was NaOH. The mass ratio of the phase transfer catalyst to 1,1,2,2,3-pentachloropropane was 0.002:1, the molar ratio of NaOH to 1,1,2,2,3-pentachloropropane was 1:1, the reaction temperature was 70℃, the dropping time was 2 h, and the holding time was 3 h. The conversion rate of 1,1,2,2,3-pentachloropropane was 98.67%, and the selectivity of 1,1,2,3-tetrachloropropene was 99.76%.
[0045] Example 3: Preparation of 1,1,2,3-tetrachloropropane from 1,1,2-trichloropropane
[0046] 1,1,2-trichloropropane was transported at a space velocity of 10 h⁻¹ -1 The material is pumped into a preheater at 100°C, and then flows into a fixed-bed reactor for pyrolysis at 350°C. The reaction liquid is recovered through a two-stage condensation system, and the tail gas is treated by water absorption, producing hydrochloric acid as a byproduct. Measurements showed that the conversion rate of 1,1,2-trichloropropane reached 85.74%; the main product was 3,3-dichloropropene with a selectivity of 96.54%, and the byproduct 1,1-dichloropropene had a selectivity of 1.73%.
[0047] The pyrolysis reaction solution was subjected to distillation, with the distillation column having 30 trays, a final reboiler temperature of 78-80℃, a vapor phase temperature of 45-50℃, a reflux ratio of 5:1, and a pressure of -0.05 MPa. Measurements showed that the normalized content of 3,3-dichloropropene was 99.97%.
[0048] High-purity 3,3-dichloropropene is chlorinated to obtain 1,1,2,3-tetrachloropropane: under normal pressure, preheating temperature 100℃, reaction temperature 150℃, and space velocity 500h⁻¹. -1 The chlorine flow rate was 200 mL / min. Measurements showed that the conversion rate of 3,3-dichloropropene was 99.91%, and the selectivity for the product 1,1,2,3-tetrachloropropane was 99.06%.
[0049] Example 4: Preparation of 1,1,2,3-tetrachloropropene from 1,1,2,3-tetrachloropropane
[0050] 1,1,2,3-Tetrachloropropane was transported at a space velocity of 10 h⁻¹ -1 The material is pumped into a preheater at 50°C, and then flows into a fixed-bed reactor for pyrolysis at 350°C. The reaction liquid is recovered through a two-stage condensation system, and the tail gas is treated by water absorption, producing hydrochloric acid as a byproduct. Measurements showed that the conversion rate of 1,1,2,3-tetrachloropropane reached 90.17%, and the selectivity for the product 1,2,3-trichloropropene was 96.34%.
[0051] 1,2,3-Trichloropropene is then chlorinated to obtain 1,1,2,2,3-pentachloropropane: under normal pressure, preheating temperature 100℃, reaction temperature 200℃, and space velocity 500 h⁻¹. -1 The chlorine flow rate was 200 mL / min, and the reaction pressure was 1.0 MPa. Measurements showed that the conversion rate of 1,2,3-trichloropropene was 99.34%, and the selectivity for 1,1,2,2,3-pentachloropropane was 99.23%.
[0052] 1,1,2,2,3-Pentachloropropane was dehydrochlorinated to obtain 1,1,2,3-Tetrachloropropene. The phase transfer catalyst was tetradecyltrimethylammonium chloride, and the base was NaOH. The mass ratio of the phase transfer catalyst to 1,1,2,2,3-pentachloropropane was 0.01:1, the molar ratio of NaOH to 1,1,2,2,3-pentachloropropane was 1.1:1, the reaction temperature was 90℃, the dropping time was 1 h, and the holding time was 1 h. The conversion rate of 1,1,2,2,3-pentachloropropane was 96.87%, and the selectivity of 1,1,2,3-tetrachloropropene was 99.14%.
[0053] Example 5: Preparation of 1,1,2,3-tetrachloropropane from 1,1,2-trichloropropane
[0054] 1,1,2-trichloropropane was transported at a space velocity of 500 h⁻¹ -1 The material is pumped into a preheater at 200℃, and then flows into a fixed-bed reactor for pyrolysis at 600℃. The reaction liquid is recovered through a two-stage condensation system, and the tail gas is treated by water absorption, producing hydrochloric acid as a byproduct. Measurements showed that the conversion rate of 1,1,2-trichloropropane reached 89.74%; the selectivity for the main product, 3,3-dichloropropene, was 91.54%, and the selectivity for the byproduct, 1,1-dichloropropene, was 5.81%.
[0055] The pyrolysis reaction solution was subjected to distillation, with the distillation column having 30 trays, a final reboiler temperature of 78-80℃, a vapor phase temperature of 45-50℃, a reflux ratio of 5:1, and a pressure of -0.05 MPa. Measurements showed that the normalized content of 3,3-dichloropropene was 99.97%.
[0056] High-purity 3,3-dichloropropene is chlorinated to obtain 1,1,2,3-tetrachloropropane: under normal pressure, preheating temperature 50℃, reaction temperature 50℃, and space velocity 100 h⁻¹. -1 The chlorine flow rate was 50 mL / min. Measurements showed that the conversion rate of 3,3-dichloropropene was 99.45%, and the selectivity for the product 1,1,2,3-tetrachloropropane was 99.46%.
[0057] Example 6: Preparation of 1,1,2,3-tetrachloropropene from 1,1,2,3-tetrachloropropane
[0058] 1,1,2,3-Tetrachloropropane was transported at a space velocity of 500 h⁻¹ -1 The material is pumped into a preheater at 100℃, and then flows into a fixed-bed reactor for pyrolysis at 600℃. The reaction liquid is recovered through a two-stage condensation system, and the tail gas is treated by water absorption, producing hydrochloric acid as a byproduct. Measurements showed that the conversion rate of 1,1,2,3-tetrachloropropane reached 85.17%, and the selectivity for the product 1,2,3-trichloropropene was 97.89%.
[0059] 1,2,3-Trichloropropene is then chlorinated to obtain 1,1,2,2,3-pentachloropropane: under normal pressure, preheating temperature 50℃, reaction temperature 80℃, and space velocity 10h⁻¹. -1 The chlorine flow rate was 50 mL / min, and the reaction pressure was 0.0 MPa. Measurements showed that the conversion rate of 1,2,3-trichloropropene was 98.17%, and the selectivity for 1,1,2,2,3-pentachloropropane was 99.67%.
[0060] 1,1,2,2,3-Pentachloropropane was dehydrochlorinated to obtain 1,1,2,3-Tetrachloropropene. The phase transfer catalyst was tetradecyl dimethyl benzyl ammonium chloride, and the base was NaOH. The mass ratio of the phase transfer catalyst to 1,1,2,2,3-pentachloropropane was 0.002:1, the molar ratio of NaOH to 1,1,2,2,3-pentachloropropane was 1:1, the reaction temperature was 90℃, the dropping time was 4 h, and the holding time was 6 h. The conversion rate of 1,1,2,2,3-pentachloropropane was 94.87%, and the selectivity of 1,1,2,3-tetrachloropropene was 98.67%.
[0061] As can be seen from the above Examples 1-2, 3-4 and 5-6, the present invention fundamentally solves the problem of the byproduct 1,1,2-trichloropropane by converting propylene chlorination byproduct 1,1,2-trichloropropane into 1,1,2,3-tetrachloropropane, and subsequently into 1,1,2,3-tetrachloropropene. Moreover, the process route is simple, the reaction conversion rate is high, and the selectivity is good.
[0062] Measurement criteria
[0063] 1. Conversion rate
[0064] In this invention, conversion rate is used to describe the proportion of reactant conversion, and the calculation formula is as follows: Conversion rate (%) = (Consumed reactants / Initially added reactants) 100% Conversion rate (%) reflects the degree to which reactants are consumed and is directly related to reaction conditions (such as temperature, time, catalyst, etc.). The higher the conversion rate, the greater the proportion of reactants that are converted.
[0065] 2. Selectivity
[0066] In this invention, the proportion of the target product among all products is selectively described, and the calculation formula is as follows: Selectivity (%) = (Amount of target product / Total amount of all products) 100% Note: The total amount of all products must be calculated based on the conversion of reactants.
[0067] Selectivity (%) reflects the specificity of the target product in the reaction system. The higher the selectivity, the greater the proportion of reactants converted into the target product and the fewer byproducts.
[0068] Although the invention has been described in conjunction with specific embodiments, those skilled in the art will understand that many modifications and variations can be made to the invention. Therefore, it is to be appreciated that the claims are intended to cover all such modifications and variations that fall within the true concept and scope of the invention.
Claims
1. A method for resource utilization of 1,1,2-trichloropropane, the method comprising: (1) A feed stream containing 1,1,2-trichloropropane was subjected to high-temperature pyrolysis to obtain a feed stream containing 3,3-dichloropropene; (2) Chlorinate the feed stream containing 3,3-dichloropropene to obtain a feed stream containing 1,1,2,3-tetrachloropropane.
2. The method according to claim 1, wherein, The method further includes: (3) The feed stream containing 1,1,2,3-tetrachloropropane was subjected to high-temperature pyrolysis to obtain a feed stream containing 1,2,3-trichloro-1-propene; (4) Chlorinate the feed stream containing 1,2,3-trichloro-1-propene to obtain a feed stream containing 1,1,2,2,3-pentachloropropane; (5) Pass the material stream containing 1,1,2,2,3-pentachloropropane through dehydrochlorination to obtain a material stream containing 1,1,2,3-tetrachloropropene.
3. The method according to claim 1, wherein, The high-temperature pyrolysis described in step (1) is carried out without a carrier gas, or in the presence of at least one inert gas selected from nitrogen, argon, helium and carbon dioxide.
4. The method according to claim 1, wherein, The conditions for high-temperature pyrolysis described in step (1) include: preheating temperature 100-200℃, reaction temperature 350-600℃, and space velocity 10-500 h⁻¹. -1 Pressure 0-2MPa.
5. The method according to claim 1, wherein, Step (1) also includes distilling the feed stream containing 3,3-dichloropropene.
6. The method according to claim 1, wherein, The chlorination in step (2) is carried out under the following conditions: preheating temperature 50-100℃, reaction temperature 50-150℃, and space velocity 100-500 h⁻¹. -1 Pressure 0-1MPa, feed flow rate 0.5-2 ml / min, chlorine flow rate 50-200 ml / min.
7. The method according to claim 2, wherein, The conditions for high-temperature pyrolysis in step (3) include: preheating temperature 50-100℃, reaction temperature 350-600℃, and space velocity 10-500 h⁻¹. -1 Pressure 0-2MPa.
8. The method according to claim 2, wherein, The chlorination described in step (4) is carried out under the following conditions: preheating temperature 50-100℃, reaction temperature 80-200℃, and space velocity 10-500 h⁻¹. -1 Pressure 0-1 MPa, chlorine flow rate 50-200 ml / min.
9. The method according to claim 2, wherein, The dehydrochlorination in step (5) is carried out in the presence of a phase transfer catalyst and a base, wherein the phase transfer catalyst is selected from one or more of hexadecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, and tetradecyldimethylbenzylammonium chloride.
10. The method according to claim 2, wherein, In step (5), the mass ratio of phase transfer catalyst to 1,1,2,2,3-pentachloropropane is (0.002-0.01):1, the molar ratio of base to 1,1,2,2,3-pentachloropropane is (1-1.1):1, the reaction temperature is 70-90℃, the dropping time is 1-4h, and the holding time is 1-6h.