阅读说明：本技术 一种液相法管道化连续化生产氟化烷烃过程中对氟化催化剂的再活化方法 (Reactivation method for fluorination catalyst in process of liquid phase method pipeline continuous production of fluorinated alkane ) 是由 沈涛 徐志雄 葛新 钱超 胡喜军 潘国东 于 2019-10-09 设计创作，主要内容包括：本发明公开一种液相法管道化连续化生产氟化烷烃过程中对氟化催化剂的再活化方法,包括以下步骤：(1)将原料从管道化反应器的入口泵入,在氟化催化剂存在下,通过加热段组或冷却段组,控制氟化反应的温度,氯化烷烃与氟化氢在管道化反应器中接触,从而进行氟化反应,得到包含中间产物和氟化烷烃的反应液物流；(2)从步骤(1)的反应液物流中分离出氟化烷烃后,剩余的反应液物流经过过滤设备,过滤出固体物质后再循环至步骤(1),将过滤出的固体物质转移至氟化催化剂再活化设备中,使用活化剂进行再活化工艺,得到再活化的氟化催化剂,并泵回管道化反应器。该法具有效果好,腐蚀小,催化剂活化后活性高的特点。(The invention discloses a reactivation method of a fluorination catalyst in the process of producing fluorinated alkane continuously by a liquid phase method in a pipeline way, which comprises the following steps: (1) pumping raw materials from an inlet of a pipeline reactor, controlling the temperature of the fluorination reaction through a heating section group or a cooling section group in the presence of a fluorination catalyst, and contacting chlorinated alkane with hydrogen fluoride in the pipeline reactor to perform the fluorination reaction to obtain a reaction liquid stream containing an intermediate product and fluorinated alkane; (2) and (2) after the fluorinated alkane is separated from the reaction liquid material flow in the step (1), the residual reaction liquid material flow passes through a filtering device, solid matters are filtered out and recycled to the step (1), the filtered solid matters are transferred to a fluorination catalyst reactivation device, a reactivation process is carried out by using an activating agent, and the reactivated fluorination catalyst is obtained and is pumped back to the pipeline reactor. The method has the characteristics of good effect, small corrosion and high activity of the activated catalyst.)

1. A reactivation method of fluorination catalyst in the process of liquid phase method pipeline continuous production of fluorinated alkane is characterized in that,

the fluorinated alkane has the following general formula:

C_nH_2n+2-x-yCl_xF_y

wherein n is an integer of 1 to 3,

it is characterized in that the preparation method is characterized in that,

the method comprises the following steps:

(1) pumping a raw material into the inlet of the pipeline reactor, wherein the raw material comprises a fluorinating agent and chlorineAlkane fluoride and fluorination catalyst, the fluorinating agent comprises hydrogen fluoride, and the fluorination catalyst is selected from one or more of antimony pentachloride, antimony chlorofluoride, stannic chloride, sulfur tetrafluoride and titanium tetrachloride; the pipeline reactor comprises a heating section group and a cooling section group, so that in the presence of the fluorination catalyst, the temperature of the fluorination reaction is controlled through the heating section group or the cooling section group, chlorinated alkane is contacted with hydrogen fluoride in the pipeline reactor, thereby the fluorination reaction is carried out, and a reaction liquid stream containing intermediate products and the fluorinated alkane is obtained, wherein the chlorinated alkane has a general formula C_nH_2n+2-x-yCl_xF_yWherein n is an integer of 1-3;

(2) separating the fluorinated alkane from the reaction liquid stream of step (1), forming the fluorinated alkane product stream, passing the remaining reaction liquid stream through a filtration device, filtering out solid matter and recycling to step (1), transferring the filtered solid matter to a fluorination catalyst reactivation device, performing a reactivation process using an activating agent selected from one or more of chlorosulfonic acid, chlorine, perchloric acid to obtain the reactivated fluorination catalyst, and pumping back to the pipeline reactor.

2. The method of claim 1, wherein the fluorinating agent further comprises one or more of potassium fluoride, mercury difluoride, and cobalt trifluoride.

3. The method of claim 1, wherein the chlorinated alkane has the general formula C_nH_2n+2-xCl_xWherein n is an integer of 1-3, and x is less than 6.

4. The method of claim 1, wherein hydrogen fluoride is fed from the front end of the heating zone stack such that in steps (1) and (2) the molar ratio of hydrogen fluoride to the intermediate product in the ducted reactor is at least 20: 1.

5. the method according to claim 1, 2, 3 or 4, wherein the reactivation process is carried out at a reactivation temperature of 50 to 100 ℃ and a reactivation pressure of 0.5 to 2.5MPa in the fluorination catalyst reactivation apparatus.

6. The method according to claim 5, wherein the weight ratio of the reactivator to the solid substance is 1: (5-50).

7. The method according to claim 1 or 6, characterized in that the feedstock comprises the reactivator in an amount of 0.05 wt% to 0.5 wt% of the feedstock.

8. The method of claim 7, wherein the reactivating agent is mixed with the fluorinated agent after being uniformly mixed with the chlorinated alkane and the fluorination catalyst.

9. The method of claim 1, wherein the pipelined reactor comprises at least two heating stage trains with an intermediate device disposed therebetween, wherein the fluorinating agent and the reactivating agent are introduced into the pipelined reactor via the intermediate device, and wherein the weight ratio of the fluorinating agent to the reactivating agent is 1: (50-1000).

10. The method of claim 1, wherein the heating section array is comprised of at least one heating section and the cooling section array is comprised of at least one cooling section.

Technical Field

The invention relates to a reactivation method of a fluorination catalyst in a liquid phase method pipeline continuous production process of fluorinated alkane.

Background

Fluorinated alkanes, as a class of substances, have a number of different applications, including as chemical intermediates, blowing agents, and refrigerants.

The fluorination process of fluorinated alkane mainly comprises the following three processes: the first, liquid phase fluorination, the second, gas phase fluorination, the third, liquid-gas combined fluorination. The liquid phase fluorination is widely applicable to production due to large production capacity per unit volume, small equipment investment and low energy consumption. The fluorination catalyst mainly comprises antimony pentachloride, tin tetrachloride, titanium tetrachloride and other transition metal compounds, wherein the most common fluorination catalyst is antimony pentachloride. In the using process, antimony pentachloride is degraded and inactivated, and chlorine gas is continuously introduced to reactivate the fluorination catalyst in order to keep the activity of the fluorination catalyst, but the corrosion of the chlorine gas to the reaction kettle at high temperature is aggravated, and the chlorine gas can be substituted with raw materials to generate other byproducts, and the chlorine gas introduced into the reaction kettle has the contact problem with the inactivated catalyst, so that the effect is poor.

The kettle reactor is a full mixed flow reactor, and chlorine reactivation and reaction can not be separated independently, so that the reaction kettle has the phenomena of corrosion and perforation, and the separation energy consumption is high. In the liquid phase method pipeline reaction, the reactivation part of the fluorination catalyst and the reaction pipeline part can be separated independently, so that the corrosion of chlorine to the reaction pipeline is prevented, other byproducts are reduced, the service life of the reaction pipeline is effectively prolonged, and the separation energy consumption is reduced. In the tubular reactor, a method for removing the deactivated catalyst is provided, and the problem is effectively solved.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a method for reactivating deactivated catalyst in the process of producing fluorinated alkane. The method has the characteristics of good effect, small corrosion and high activity of the activated catalyst.

The purpose of the invention is realized as follows:

a reactivation method of a fluorination catalyst in the process of continuously producing fluorinated alkane by a liquid phase method in a pipeline way,

the fluorinated alkane has the following general formula:

C_nH_2n+2-x-yCl_xF_y

wherein n is an integer of 1 to 3,

the method comprises the following steps:

(1) pumping a feedstock from an inlet of a piping reactor, the feedstock comprising a fluorinating agent, a chlorinated alkane, and a fluorination catalyst, the fluorinating agent comprising hydrogen fluoride, the fluorination catalyst selected from one or more of antimony pentachloride, antimony chlorofluoride, tin tetrachloride, sulfur tetrafluoride, and titanium tetrachloride; the pipeline reactor comprises a heating section group and a cooling section group, so that in the presence of the fluorination catalyst, the temperature of the fluorination reaction is controlled through the heating section group or the cooling section group, chlorinated alkane is contacted with hydrogen fluoride in the pipeline reactor, thereby the fluorination reaction is carried out, and a reaction liquid stream containing intermediate products and the fluorinated alkane is obtained, wherein the chlorinated alkane has a general formula C_nH_2n+2-x-yCl_xF_yWherein n is an integer of 1-3;

(2) separating said fluorinated alkane from said reaction liquid stream of step (1), forming said fluorinated alkane product stream, passing the remaining reaction liquid stream through a filtration unit, filtering out solid material and recycling to step (1), transferring said filtered solid material to a fluorination catalyst reactivation unit, performing a reactivation process using an activating agent to obtain said reactivated fluorination catalyst, and pumping back to said pipeline reactor, said reactivation agent being selected from one or more of chlorosulfonic acid, chlorine, perchloric acid.

Preferably, the fluorinating agent further comprises one or more of potassium fluoride, mercury difluoride and cobalt trifluoride.

Preferably, the chlorinated alkane has the general formula C_nH_2n+2-xCl_xWherein n is an integer of 1-3, and x is less than 6.

Preferably, hydrogen fluoride is additionally added from the front end of the heating section group, so that in the steps (1) and (2), the molar ratio of the hydrogen fluoride to the intermediate product in the pipelining reactor is at least 20: 1.

further, when the reactivation process is carried out, the reactivation temperature is 50-100 ℃ and the reactivation pressure is 0.5-2.5MPa in the fluorination catalyst reactivation equipment.

Further, the weight ratio of the reactivator to the solid matter is 1: (5-50).

Further, the raw material comprises the re-activating agent, and the content of the re-activating agent in the raw material is 0.05 wt% to 0.5 wt%.

Further, the reactivator is mixed with the chlorinated alkane and the fluorination catalyst uniformly, and then mixed with the fluorination agent.

Preferably, the pipeline reactor at least comprises two heating section groups, an intermediate device is arranged between the heating section groups, the pipeline reactor is fed with the fluorinating agent and the reactivating agent through the intermediate device, and the weight ratio of the fluorinating agent to the reactivating agent is 1: (50-1000).

Preferably, the heating section group consists of at least one heating section, and the cooling section group consists of at least one cooling section.

Preferably, the fluorination reaction temperature is 50-120 ℃, and the fluorination pressure is 0.2-2 MPa.

The invention has the following beneficial effects:

1. the reactivation process of the fluorination catalyst can be carried out in a separate device, the temperature for reactivating the fluorination catalyst is reduced, and the reactivation of the fluorination catalyst in a pipeline reactor can be reduced or even avoided, so that the corrosion rate of the reactor can be obviously reduced;

2. the method for producing fluorinated alkane in a pipeline manner by using the liquid phase method can separate a fluorinated catalyst regeneration reactivation system from a fluorination reaction system, so that the fluorinated catalyst to be reactivated can be separated from the fluorination reaction firstly and then subjected to reactivation reaction, and the reactivation efficiency is improved; compared with the traditional technology that the reactivation is carried out in a reaction kettle, the reactivation catalyst is not separated from the fluorination reaction, and the reactivation catalyst obtained by the reactivation has higher purity and better activity, so that the selectivity of the fluorination reaction is obviously higher than that of a kettle-type reactor.

Detailed Description

The present invention is further illustrated by the following examples, which are not intended to limit the invention to these embodiments. It will be appreciated by those skilled in the art that the present invention encompasses all alternatives, modifications and equivalents as may be included within the scope of the claims.

In the present invention, the raw materials and equipment used are commercially available or commonly used in the art, unless otherwise specified. The methods in the following examples are conventional in the art unless otherwise specified.

Preparation example

A reactivation method of a fluorination catalyst in the process of continuously producing fluorinated alkane by a liquid phase method in a pipeline way,

the fluorinated alkane has the following general formula:

C_nH_2n+2-x-yCl_xF_y

wherein n is an integer of 1 to 3,

the method comprises the following steps:

(1) pumping a feedstock from an inlet of a piping reactor, the feedstock comprising a fluorinating agent, a chlorinated alkane, and a fluorination catalyst, the fluorinating agent comprising hydrogen fluoride, the fluorination catalyst selected from one or more of antimony pentachloride, antimony chlorofluoride, tin tetrachloride, sulfur tetrafluoride, and titanium tetrachloride; the piping reactor comprises a heating section group and a cooling section group, so that the fluorination catalyst passes through the heating section group or the heating section groupThe cooling section group controls the temperature of the fluorination reaction, and the chlorinated alkane is contacted with hydrogen fluoride in the pipeline reactor so as to carry out the fluorination reaction and obtain a reaction liquid stream containing an intermediate product and the fluorinated alkane, wherein the chlorinated alkane has a general formula C_nH_2n+2-x-yCl_xF_yWherein n is an integer of 1-3;

(2) separating said fluorinated alkane from said reaction liquid stream of step (1), forming said fluorinated alkane product stream, passing the remaining reaction liquid stream through a filtration unit, filtering out solid material and recycling to step (1), transferring said filtered solid material to a fluorination catalyst reactivation unit, performing a reactivation process using a reactivation agent selected from one or more of chlorosulfonic acid, chlorine, perchloric acid to obtain said reactivated fluorination catalyst, and pumping back to said pipeline reactor.

Specifically, a feedstock is pumped from an inlet of the pipelined reactor, the feedstock comprising a fluorinating agent selected from one or more of hydrogen fluoride, potassium fluoride, mercury difluoride, cobalt trifluoride, and a fluorination catalyst, the chlorinated alkane having the general formula C_nH_2n+2-xCl_xWherein n is an integer of 1-3, x is less than 6, and the fluorination catalyst is one or more selected from antimony pentachloride, antimony chlorofluoride, stannic chloride, sulfur tetrafluoride and titanium tetrachloride; the raw materials are mixed into a reaction solution in the pipeline reactor; the pipeline reactor comprises at least two sections of heating sections, the heating sections of the pipeline reactor are connected in series, an intermediate device is connected between the heating sections of the tubular reactor, and the pipeline reactor is heated to the corresponding fluorination reaction temperature; filling pressurized gas into a pipeline reactor to a fluorination pressure, enabling the reaction liquid to flow through a heating section of the pipeline reactor at a flow rate of 0.1-3m/s, carrying out a fluorination reaction in the heating section of the pipeline reactor, enabling the reaction liquid to flow to an intermediate device, gasifying the fluorinated alkane in the reaction liquid in the intermediate device to form a fluorinated alkane gas flow, and enabling the fluorinated alkane gas flow to a gas-liquid separation device(ii) a The reaction liquid flows through the pipeline reactor to carry out fluorination reaction to form reaction effluent liquid; pumping the reaction effluent liquid out of an outlet of the pipeline reactor, and pumping the reaction effluent liquid to the gas-liquid separation device for pre-separation; the reaction effluent or the fluorinated alkane gas flow is pre-separated into a gas phase material and a liquid phase material in the gas-liquid separation device, wherein the gas phase material contains the fluorinated alkane, and the liquid phase material contains the fluorination catalyst, unreacted fluorinated alkane and the fluorinating agent; filtering solid substances in the liquid phase material by using a filtering device, and pumping the liquid phase material back to the pipeline reactor; transferring the solid matter to a fluorination catalyst reactivation apparatus, performing a reactivation process using a reactivation agent selected from one or more of chlorosulfonic acid, chlorine, perchloric acid to obtain the reactivated fluorination catalyst, and pumping back to the pipeline reactor.

The method comprises the steps of firstly, uniformly mixing raw materials including a fluorinating agent, chlorinated alkane and a fluorination catalyst, introducing the mixture into a pipeline reactor, and carrying out fluorination reaction at the fluorination reaction temperature and the fluorination reaction pressure; preferably, the chlorinated alkane and the fluorination catalyst are mixed in advance and then mixed with the fluoride;

preferably, the fluorination reaction temperature is 50-120 ℃, and the fluorination pressure is 0.2-2 MPa;

preferably, the raw material comprises the reactivator, and the content of the reactivator in the raw material is 0.05 wt% to 0.5 wt%; further, the reactivating agent is uniformly mixed with the chlorinated alkane and the fluorination catalyst, and then is mixed with the fluorinating agent; aims to reactivate a fluorination catalyst in a pipeline reactor, thereby maintaining the efficiency of the fluorination reaction and reducing the occurrence of side reactions.

The reaction liquid flows through the heating section of the pipeline reactor and is subjected to fluorination reaction at the fluorination reaction temperature and the fluorination reaction pressure; the reaction liquid flows to a subsequent intermediate device adjacent to the reaction liquid after flowing through the section heating section of the pipeline reactor, wherein the reaction liquid comprises an intermediate product, generated fluorinated alkane, unreacted raw materials and a fluorination catalyst, partial fluoride and chlorinated alkane are consumed, the fluorination catalyst is also partially fluorinated, and the reaction liquid contains the generated fluorinated alkane in the intermediate device and is gasified to form a fluorinated alkane gas flow to a gas-liquid separation device;

further, feeding the fluorinating agent and the reactivating agent to the pipeline reactor through the intermediate device, wherein the weight ratio of the fluorinating agent to the reactivating agent is 1: (50-1000); aims to reactivate a fluorination catalyst in a pipeline reactor so as to maintain the efficiency of the fluorination reaction;

the reaction liquid flows through the pipeline reactor to carry out fluorination reaction to form reaction effluent liquid; pumping the reaction effluent liquid out of an outlet of the pipeline reactor, and pumping the reaction effluent liquid to the gas-liquid separation device for pre-separation; the reaction effluent or the fluorinated alkane gas flow is pre-separated into a gas phase material and a liquid phase material in the gas-liquid separation device, wherein the gas phase material contains the fluorinated alkane, and the liquid phase material contains the fluorination catalyst, unreacted fluorinated alkane and the fluorinating agent; pumping the liquid phase material back to the pipeline reactor, and pumping the gas phase material into a purification device; after the gas-phase material is subjected to a separation procedure in the purification device, separating out the fluorinated alkane to obtain a finished product; before the liquid phase material is pumped back to the pipeline reactor, solid matters in the liquid phase material are filtered out through a filtering device, aiming at filtering out fluorination catalyst inactivated by fluorination and other impurities in reaction liquid, so that side reactions are reduced, on the other hand, precondition is provided for a process of reactivation of the fluorination catalyst in a separate device, the solid matters are transferred to a device for reactivation of the fluorination catalyst, and reactivated to obtain the reactivated fluorination catalyst, and the liquid phase material is pumped back to the pipeline reactor, aiming at reactivating the fluorination catalyst in a separate device, so that the temperature of the reactivated fluorination catalyst is reduced, and the corrosion rate of the reactor can be remarkably reduced as the reactivation of the fluorination catalyst in the pipeline reactor can be reduced or even avoided;

preferably, when the reactivation process is carried out, in the reactivation equipment of the fluorination catalyst, the reactivation temperature is 50-100 ℃, and the reactivation pressure is 0.5-2.5 MPa; further, transferring a reactivation agent and the solid matter to a fluorination catalyst reactivation apparatus, the weight ratio of reactivation agent to solid matter being 1: (5-50), the reactivator is one or more selected from chlorosulfonic acid, chlorine and perchloric acid; the method has the advantages that a fluorination catalyst is reactivated, so that the fluorination reaction efficiency is kept, a regeneration reactivation system and a reaction system of the fluorination catalyst are separated in the method, the fluorination catalyst system can be separated firstly and then further reactivated, the reactivation efficiency is improved, and in addition, the regenerated and reactivated fluorination catalyst enters the reaction system and is reactivated in a reaction kettle in comparison with the traditional technology, so that the purity is higher, the activity is better, and the reaction selectivity is obviously higher than that of a kettle type reactor;

the process of the present invention is compared to prior art processes by synthesizing specific fluorinated alkanes.