阅读说明：本技术 一种液相法管道化连续分离生产氟化烷烃的装置 (Device for producing fluorinated alkane through liquid phase method pipelining continuous separation ) 是由 童绍丰 陈新志 葛新 赵恒军 钱超 符仁华 于 2019-10-09 设计创作，主要内容包括：本发明提供一种液相法管道化连续分离生产氟化烷烃的装置,所使用的管道化反应生产装置包括催化剂储罐、氯化烷烃储罐、氟化氢储罐、管式反应器、加热箱、稳压罐、第一分离装置和第一产品储罐；催化剂储罐、氯化烷烃储罐和氟化氢储罐分别连接至管式反应器的入口；反应段置于具有加热介质的加热箱中,反应段之间连接有第一气液分离器,冷却段连接至稳压罐,在稳压罐的上部设置有气相出口,气相出口连接至第一分离装置,第一分离装置连接至第一产品储罐,在稳压罐的底部设置有液相出口,液相出口连接至管式反应器的入口。本发明的装置,适用于原料包括氢氟酸的氟化反应,该装置具有使用通用设备、投资小、工艺简单、无污染、产品纯度较高等优点。(The invention provides a device for producing fluorinated alkane by liquid phase method pipelining continuous separation, wherein the used pipelining reaction production device comprises a catalyst storage tank, a chlorinated alkane storage tank, a hydrogen fluoride storage tank, a tubular reactor, a heating box, a pressure stabilizing tank, a first separation device and a first product storage tank; the catalyst storage tank, the chlorinated alkane storage tank and the hydrogen fluoride storage tank are respectively connected to the inlet of the tubular reactor; the reaction section is arranged in a heating box with a heating medium, a first gas-liquid separator is connected between the reaction sections, the cooling section is connected to a pressure stabilizing tank, a gas-phase outlet is arranged on the upper portion of the pressure stabilizing tank and connected to a first separation device, the first separation device is connected to a first product storage tank, a liquid-phase outlet is arranged at the bottom of the pressure stabilizing tank, and the liquid-phase outlet is connected to an inlet of the tubular reactor. The device is suitable for the fluorination reaction of raw materials including hydrofluoric acid, and has the advantages of using general equipment, small investment, simple process, no pollution, high product purity and the like.)

1. A device for continuously separating and producing fluorinated alkane in a pipeline way by a liquid phase method 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,

the used pipeline reaction production device comprises a catalyst storage tank (1), a chlorinated alkane storage tank (2), a hydrogen fluoride storage tank (3), a tubular reactor, a heating box, a pressure stabilizing tank (14), a first separation device and a first product storage tank (21); the catalyst storage tank (1), the chlorinated alkane storage tank (2) and the hydrogen fluoride storage tank (3) are respectively connected to the inlet of a tubular reactor, the tubular reactor at least comprises a first reaction section (8), a second reaction section (10) and a cooling section (13), the first reaction section (8) is arranged at the inlet of the tubular reactor, the second reaction section (10) is arranged between the first reaction section (8) and the cooling section (13), and the cooling section (13) is arranged at the outlet of the tubular reactor; the first reaction section (8) and the second reaction section (10) are respectively arranged in a heating box with a heating medium, a first gas-liquid separator (9) is connected between the first reaction section (8) and the second reaction section (10), the cooling section (13) is connected to the pressure stabilizing tank (14), a gas-phase outlet is arranged at the upper part of the pressure stabilizing tank (14), the gas-phase outlet is connected to the first separation device, the first separation device is connected to the first product storage tank (21), a liquid-phase outlet is arranged at the bottom of the pressure stabilizing tank (14), and the liquid-phase outlet is connected to an inlet of the tubular reactor.

2. The apparatus according to claim 1, wherein the pipeline reaction production apparatus further comprises a first metering pump (5), a second metering pump (6) and a premixing tank (4), the catalyst storage tank (1) and the chlorinated alkane storage tank (2) are connected to the premixing tank (4), the premixing tank (4) is connected to the inlet of the tubular reactor after being connected to the second metering pump (6), and the hydrogen fluoride storage tank (3) is connected to the inlet of the tubular reactor after being connected to the first metering pump (5).

3. The apparatus according to claim 2, characterized in that a first preheating device is arranged after the second metering pump (6) and between the inlet of the tubular reactor, and a second preheating device is arranged between the first metering pump (5) and the inlet of the tubular reactor.

4. An apparatus according to claim 1 or 2, characterized in that the first gas-liquid separator (9) is connected to a second separation device, which is connected to the first product tank (21) or a second product tank (22).

5. The plant according to claim 1, characterized in that the pipelined reaction production plant further comprises a premix tank (4), the bottom of the first rectification column (19) or the second rectification column (20) being provided with a liquid phase outlet connected to the premix tank (4).

6. The device according to claim 5, characterized in that the first metering pump (5) is connected to the inlet of the tubular reactor after having passed through the static mixer (7).

7. The device according to claim 6, characterized in that the second metering pump (6) is connected to the inlet of the tubular reactor after the static mixer (7).

8. The apparatus of claim 1, wherein the tubular reactor is one or a combination of several of a straight tube reactor, a coil tube reactor, a multi-tube reactor, a U-tube reactor, and a loop tube reactor.

9. The apparatus of claim 1, wherein the material of the tubular reactor is one or more of carbon steel, brass, stainless steel, monel, hastelloy.

10. The apparatus of claim 1, 8 or 9, wherein the tubular reactor has an inner liner made of polyperfluoroolefin or carbon fiber.

Technical Field

The invention relates to a device for continuously separating and producing fluorinated alkane in a pipeline way by a liquid phase method.

Background

The fluorinated alkane is used as a substitute of Freon refrigerant, and has zero ozone loss potential and good thermodynamic property. The prior preparation methods of the fluorinated alkane mainly comprise a liquid phase fluorination method and a gas phase fluorination method, and the liquid phase fluorination method is widely adopted due to large production capacity and low energy consumption. However, the problem of reactor corrosion caused by the liquid phase fluorination method has not been solved effectively.

Disclosure of Invention

In order to meet the industrial requirements on different fluorinated alkanes, the invention provides the device for producing the fluorinated alkanes by the liquid phase method through the pipelining continuous separation, which is suitable for the fluorination reaction of raw materials including hydrofluoric acid.

The purpose of the invention is realized as follows:

a device for continuously separating and producing fluorinated alkane in a pipeline way by a liquid phase method,

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 used pipeline reaction production device comprises a catalyst storage tank (1), a chlorinated alkane storage tank (2), a hydrogen fluoride storage tank (3), a tubular reactor, a heating box, a pressure stabilizing tank (14), a first separation device and a first product storage tank (21); the catalyst storage tank (1), the chlorinated alkane storage tank (2) and the hydrogen fluoride storage tank (3) are respectively connected to the inlet of a tubular reactor, the tubular reactor at least comprises a first reaction section (8), a second reaction section (10) and a cooling section (13), the first reaction section (8) is arranged at the inlet of the tubular reactor, the second reaction section (10) is arranged between the first reaction section (8) and the cooling section (13), and the cooling section (13) is arranged at the outlet of the tubular reactor; the first reaction section (8) and the second reaction section (10) are respectively arranged in a heating box with a heating medium, a first gas-liquid separator (9) is connected between the first reaction section (8) and the second reaction section (10), the cooling section (13) is connected to the pressure stabilizing tank (14), a gas-phase outlet is arranged at the upper part of the pressure stabilizing tank (14), the gas-phase outlet is connected to the first separation device, the first separation device is connected to the first product storage tank (21), a liquid-phase outlet is arranged at the bottom of the pressure stabilizing tank (14), and the liquid-phase outlet is connected to an inlet of the tubular reactor.

Preferably, the pipeline reaction production device further comprises a first metering pump (5), a second metering pump (6) and a premixing tank (4), wherein the catalyst storage tank (1) and the chlorinated alkane storage tank (2) are connected to the premixing tank (4), the premixing tank (4) is connected to the inlet of the tubular reactor after being connected to the second metering pump (6), and the hydrogen fluoride storage tank (3) is connected to the inlet of the tubular reactor after being connected to the first metering pump (5).

Furthermore, a first preheating device is arranged between the rear part of the second metering pump (6) and the inlet of the tubular reactor, and a second preheating device is arranged between the first metering pump (5) and the inlet of the tubular reactor.

Further, the liquid phase outlet is connected to the premix tank (4).

Further, the hydrogen fluoride storage tank (3) is also connected to the premix tank (4).

Further, the first gas-liquid separator (9) is connected to a second separation device, which is connected to the first product tank (21) or a second product tank (22).

Preferably, the tubular reactor further comprises a third reaction section (12), and a second gas-liquid separator (11) is connected between the second reaction section (10) and the third reaction section (12).

Further, the second gas-liquid separator (11) is connected to a second separation device.

Further, the first separation device comprises a first deacidification device and a first rectifying tower (19), and the second separation device comprises a second deacidification device and a second rectifying tower (20).

Further, first separator includes at least two sets of first deacidification device through the parallel mode is connected, second separator includes at least two sets of second deacidification device through the parallel mode is connected.

Further, the first deacidification device comprises a first water washing tower (15) and a first alkaline washing tower (16), the second deacidification device comprises a second water washing tower (17) and a second alkaline washing tower (18), the first water washing tower (15) is connected with the first alkaline washing tower (16) and then connected with the first rectifying tower (19) and then connected to the first product storage tank (21), and the second water washing tower (15) is connected with the second alkaline washing tower (16) and then connected with the second rectifying tower (20) and then connected to the first product storage tank (21) or the second product storage tank (22).

Further, the bottom of the first rectifying tower (19) or the second rectifying tower (20) is provided with a liquid phase outlet, and the liquid phase outlet is connected to the inlet of the tubular reactor.

Further, the pipeline reaction production device further comprises a premixing tank (4), the bottom of the first rectifying tower (19) or the bottom of the second rectifying tower (20) is provided with a liquid phase outlet, and the liquid phase outlet is connected to the premixing tank (4).

Furthermore, sampling ports are arranged at the upper parts of the first alkaline washing tower (16) and the second alkaline washing tower (18).

Furthermore, the first metering pump (5) passes through the static mixer (7) and then is connected with the inlet of the tubular reactor.

Furthermore, the second metering pump (6) is connected with the inlet of the tubular reactor after being connected with the static mixer (7).

Further, the surge tank (14) or the premixing tank (4) is also provided with a pressurized gas inlet, so that pressurized gas can be conveniently introduced.

Preferably, the tubular reactor is one or a combination of several of a straight tube reactor, a coil tubular reactor, a multi-tubular reactor, a U-shaped tubular reactor and a loop tubular reactor.

Preferably, the material of the tubular reactor is one or more of carbon steel, brass, stainless steel, monel and hastelloy.

Furthermore, the tubular reactor is provided with a lining, and the lining is made of polyperfluoroolefin or carbon fiber.

The invention has the following beneficial effects:

1. the invention provides a device for producing fluorinated alkane by liquid phase method pipelining continuous separation, which is suitable for fluorination reaction of raw materials including hydrogen fluoride and chlorinated alkane.

2. The yield per unit volume of the device is superior to that of a kettle reactor in the prior art, so that the efficiency of producing fluorinated alkane is improved, and the device has the characteristics of good process safety, easy control of reaction conditions, stable product quality and the like, and is more favorable for industrial production; the device of the invention adopts corrosion-resistant materials, so that the corrosive raw material hydrogen fluoride does not gather at a specific part of the equipment in the fluorination reaction, thereby reducing the corrosion to the equipment, leading the catalyst to have better activity and longer service life.

3. In the device, the reaction part and the catalyst activation part are separated, so that the corrosion of the activation to the reactor is reduced, and the accumulation of the inactivated catalyst in the reactor is avoided; because the device adopts the channeling reaction and recycles the raw materials, the utilization rate of the raw materials can be effectively improved, the unit volume capacity of the reactor is greatly improved, and the poly-generation of the same series of products can be realized.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to the drawings.

FIG. 1 is a schematic connection diagram of a device for producing fluorinated alkanes by continuous separation in a pipeline manner by using a liquid phase method according to an embodiment of the invention;

the system comprises a catalyst storage tank 1, a paraffin chloride storage tank 2, a hydrogen fluoride storage tank 3, a premixing tank 4, a first metering pump 5, a second metering pump 6, a static mixer 7, a first reaction section 8, a first gas-liquid separator 9, a second reaction section 10, a second gas-liquid separator 11, a third reaction section 12, a cooling section 13, a pressure stabilizing tank 14, a first washing tower 15, a first alkaline washing tower 16, a second washing tower 17, a second alkaline washing tower 18, a first rectifying tower 19, a second rectifying tower 20, a first product storage tank 21 and a second product storage tank 22.

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. The terms "first," "second," and the like in the present disclosure are used for distinguishing between descriptions and not to imply or imply relative importance.

A device for continuously separating and producing fluorinated alkane in a pipeline way by a liquid phase method,

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 used pipeline reaction production device comprises a catalyst storage tank 1, a chlorinated alkane storage tank 2, a hydrogen fluoride storage tank 3, a tubular reactor, a heating box, a pressure stabilizing tank 14, a first separation device and a first product storage tank 21; the catalyst storage tank 1, the chlorinated alkane storage tank 2 and the hydrogen fluoride storage tank 3 are respectively connected to the inlet of a tubular reactor, the tubular reactor at least comprises a first reaction section 8, a second reaction section 10 and a cooling section 13, the first reaction section (8) is arranged at the inlet of the tubular reactor, the second reaction section (10) is arranged between the first reaction section (8) and the cooling section (13), and the cooling section (13) is arranged at the outlet of the tubular reactor; the first reaction section (8) and the second reaction section (10) are respectively arranged in a heating box with a heating medium, a first gas-liquid separator (9) is connected between the first reaction section (8) and the second reaction section (10), the cooling section (13) is connected to the pressure stabilizing tank (14), a gas-phase outlet is arranged at the upper part of the pressure stabilizing tank (14), the gas-phase outlet is connected to the first separation device, the first separation device is connected to the first product storage tank (21), a liquid-phase outlet is arranged at the bottom of the pressure stabilizing tank (14), and the liquid-phase outlet is connected to an inlet of the tubular reactor.

In this embodiment, the used pipeline reaction production device includes a catalyst storage tank 1, a chlorinated alkane storage tank 2, a hydrogen fluoride storage tank 3, a premixing tank 4, a first metering pump 5, a second metering pump 6, a static mixer 7, a first reaction section 8, a first gas-liquid separator 9, a second reaction section 10, a second gas-liquid separator 11, a third reaction section 12, a cooling section 13, a pressure stabilizing tank 14, a first water scrubber 15, a first caustic tower 16, a second water scrubber 17, a second caustic tower 18, a first rectifying tower 19, a second rectifying tower 20, a first product storage tank 21, and a second product storage tank 22; the catalyst storage tank 1, the alkane chloride storage tank 2 and the hydrogen fluoride storage tank 3 are connected to the premixing tank 4, the premixing tank 4 is further provided with a pressurized gas inlet, the premixing tank 4 is connected to an inlet of a tubular reactor after being connected with the second metering pump 6, the hydrogen fluoride storage tank 3 is connected to an inlet of the tubular reactor after being connected with the first metering pump 5, the tubular reactor comprises at least two sections of reaction sections 8 and 10, the reaction sections 8 and 10 are arranged in a heating box with a heating medium, a gas-liquid separator 9 and 11 is connected between the reaction sections 8 and 10 of the tubular reactor, an outlet of the tubular reactor is connected to the pressure stabilizing tank 14 through a cooling section 13, a gas phase outlet is arranged at the upper part of the pressure stabilizing tank 14 and is connected to the separation device, and the separation device is connected to the product storage tank 21, and 22, a liquid phase outlet is arranged at the bottom of the pressure stabilizing tank 14 and is connected to the premixing tank 4.

The raw materials for synthesizing the fluorinated alkane by the liquid phase method comprise hydrogen fluoride, chlorinated alkane and a catalyst, wherein the catalyst is generally antimony pentachloride, and one or more of antimony pentachloride, antimony trichloride, stannic chloride, sulfur tetrafluoride and titanium tetrachloride can be selected as an auxiliary catalyst; the raw material storage tanks at least comprise three catalyst storage tanks 1 for storing catalysts, chlorinated alkane storage tanks 2 for storing chlorinated alkanes and hydrogen fluoride storage tanks 3 for storing hydrogen fluoride; preferably, the raw material storage tank further comprises a cocatalyst storage tank and an activator storage tank, wherein the cocatalyst storage tank stores one or more of tin tetrachloride, sulfur tetrafluoride and titanium tetrachloride, and the activator storage tank stores one or more of chlorosulfonic acid, chlorine and perchloric acid;

in the device, the selected raw materials for synthesizing the fluorinated alkane comprise hydrogen fluoride, chlorinated alkane and a catalyst, wherein the hydrogen fluoride flows out of a hydrogen fluoride storage tank 3 and is metered by a first metering pump, and the mass and the speed of the hydrogen fluoride introduced into a pipeline reactor are controlled; after the chlorinated alkane and the catalyst are mixed in the premixing tank 4 according to a certain proportion, the chlorinated alkane and the catalyst are metered by a second metering pump, and the mass and the speed of the chlorinated alkane and the catalyst which are introduced into the pipeline reactor are controlled;

preferably, the catalyst storage tank 1 is connected to the premixing tank 4, and the mass and speed of the catalyst introduced into the premixing tank 4 are controlled;

preferably, the chlorinated alkane storage tank 2 is connected to the premixing tank 4, and the mass and the speed of the chlorinated alkane introduced into the premixing tank 4 are controlled;

simultaneously introducing a pressurized gas into the tubular reactor, and pressurizing to the fluorination reaction pressure, wherein the fluorination reaction pressure is generally 0.6-3MPa, the pressurized gas is generally an inert gas, the inert gas is one of nitrogen, helium or argon, and the commonly used pressurized gas is generally nitrogen; the tubular reactor comprises at least two reaction sections 8 and 10, the tubular reactors 8 and 10 are placed in an oil bath filled with heating media, the first reaction section of the tubular reactor is heated to the fluorination reaction temperature, generally 60-130 ℃, hydrogen fluoride and chlorinated alkane in raw material flow are subjected to fluorination reaction in the tubular reactor under the catalysis of a catalyst, the generated reaction liquid comprises fluorinated alkane which is a product of the fluorination reaction, the generated reaction liquid also comprises unreacted raw materials and the catalyst, and a gas-liquid separator is connected between the reaction sections of the tubular reactor;

preferably, the first metering pump 5 is connected with the preheating device and then connected with the inlet of the tubular reactor;

further, the second metering pump 6 is connected with the preheating device and then connected with the inlet of the tubular reactor;

the raw materials passing through the first metering pump 5 are preheated, so that firstly, the reaction time is accurately controlled, the abundant heat of the reaction is fully utilized, secondly, the reaction starting temperature is increased, the length and corrosion of a high-temperature reaction pipeline are reduced, and in addition, the restriction effect of products generated after the temperature is lower on the reaction balance is avoided; preheating temperature range: normal temperature < preheating temperature < reaction temperature;

preheating the raw material passing through the second metering pump 6, wherein the preheating temperature range is as follows: normal temperature < preheating temperature;

further, the preheating temperature of the raw material passing through the second metering pump 6 is lower than that of the raw material passing through the first metering pump 5, and the preheating temperature is not too high due to the existence of thermal decomposition substances in the raw material passing through the second metering pump 6; the preheating temperature of the raw material passing through the first metering pump 5 is high, so that more heat can be provided for the reaction in the prior art, the subsequent heat supply pressure is reduced, the temperature difference between the raw material passing through the second metering pump 6 and the raw material is large, and the heat transfer effect is improved;

preferably, the hydrogen fluoride storage tank 3 is also connected to the premix tank 4 or an intermediate line; the hydrogen fluoride storage tank 3 is connected to the premixing tank 4 for activating the catalyst, and the hydrogen fluoride storage tank 3 is connected to the intermediate pipeline for supplementing hydrogen fluoride consumed by the fluorination reaction in the heating section of the tubular reactor at the previous stage into the reaction solution, so that the concentration of the hydrogen fluoride in the reaction solution is maintained, the reaction solution is subjected to the fluorination reaction in the heating section of the reactor at the next stage, the reaction speed and efficiency are good, and the occurrence of side reactions is reduced;

under the action of a catalyst, carrying out a fluorination reaction on raw materials which are not reacted in a reaction solution in a first-stage reaction section 8 in the tubular reactor, and enabling the reaction solution to flow out to an intermediate pipeline connected with the first reaction section 8, wherein the intermediate pipeline is connected to a first gas-liquid separator 9; repeating the steps for a plurality of times until the last first reaction section and the last second reaction section are reached, wherein the reaction liquid flows out of the last first reaction section and the last second reaction section and flows into the pressure stabilizing tank 14;

preferably, the tubular reactor further comprises at least one cooling section 13 disposed at the rear end of the tubular reactor, and the cooling section 13 of the tubular reactor is disposed in a cooling tank filled with a cooling medium, so as to, on one hand, rapidly cool the reaction solution to accurately control the reaction time and avoid the generation of unnecessary byproducts, and on the other hand, cool the reaction solution flowing out of the last heating section 12 to a reasonable temperature, generally 40-80 ℃, before flowing into the surge tank 14, for separation;

in the pressure stabilizing tank 14, the fluorinated alkane material flow from the intermediate device or the reaction liquid flowing out from the last heating section 12 is separated into a gas phase material containing fluorinated alkane and a liquid phase material containing unreacted raw materials and catalysts, the gas phase material flows to a separation device through a gas phase outlet arranged at the upper part of the pressure stabilizing tank 14, after relevant impurities are separated and removed, the obtained fluorinated alkane flows into a product storage tank 21, and the liquid phase material flows to the premixing tank 4 and the hydrogen fluoride storage tank 3 from the liquid phase outlet of the pressure stabilizing tank 14, so that the raw materials for synthesizing fluorinated alkane are recycled, and the technical purpose of continuously synthesizing fluorinated alkane is realized;

preferably, a liquid phase outlet is arranged at the bottom of the pressure stabilizing tank 14, and the liquid outlet is connected with the inlet of the tubular reactor, the premixing tank 4 or the hydrogen fluoride storage tank 3;

further, the upper part of the pressure stabilizing tank 14 is also provided with a pressurized gas inlet for facilitating the introduction of the pressurized gas, and the purpose is to adjust the air pressure in the pressure stabilizing tank and a pipeline, so that the effect of separating the gas-phase material and the liquid-phase material is better;

preferably, the separation device comprises a deacidification device, a drying device and a rectification device 19, wherein the deacidification device comprises a water washing device 15 and a caustic washing device 16; further, the separation device comprises at least two groups of deacidification devices connected in parallel; the method aims to separate and remove impurities, mainly hydrogen fluoride and hydrogen chloride, in gas phase materials containing fluorinated alkane so as to obtain the product fluorinated alkane prepared by the device;

further, a first sampling port is arranged at the upper part of the alkaline washing device 16, and a second sampling port is arranged at the upper part of the alkaline washing device 18; the method aims to detect the content of impurities in the obtained fluorinated alkane product, so that production personnel can adjust related reaction conditions in time to achieve a better reaction effect;

further, a liquid phase outlet of the rectification device is arranged at the bottom of the rectification device 20, and the liquid phase outlet of the rectification device is connected to the inlet of the tubular reactor or the premixing tank 4; the method aims to realize the synthesis of the final fluorinated alkane by performing the fluorination reaction on the intermediate product through rectifying and separating the intermediate product to the inlet of the tubular reactor or the premixing tank 4, thereby realizing the synthesis utilization rate of the raw material for synthesizing the fluorinated alkane, and realizing the technical purposes of environmental protection, energy conservation, no pollution and reduction of the production cost for synthesizing the fluorinated alkane;

preferably, the separation device is connected with the compression device and then connected with the product storage tank, so as to improve the efficiency of placing the generated fluorinated alkane into the product storage tank;

preferably, the tubular reactor is one or a combination of several of a straight tubular reactor, a coil tubular reactor, a multi-tubular reactor, a U-shaped tubular reactor and an annular tubular reactor; the method aims to ensure that raw materials for synthesizing fluorinated alkane can fully perform fluorination reaction in a tubular reactor, the flow rate and the composition, structure and length of the tubular reactor determine the reaction residence time, and the reaction residence time is changed by adjusting the flow rate under the condition determined by the tubular reactor; changing the reaction residence time by changing the composition, structure and length of the tubular reactor under the condition of determined flow rate; the flow rate is generally 0.1 to 3.0 m/s;

preferably, the material of the tubular reactor is one or more of carbon steel, brass, stainless steel, monel and hastelloy; aims to ensure that the tubular reactor can resist corrosion when the raw material for synthesizing fluorinated alkane is subjected to fluorination reaction in the tubular reactor;

further, the tubular reactor is provided with a lining, and the lining is made of polyperfluoroolefins or carbon fibers; the tubular reactor is smaller in system and simple in internal structure, so that the tubular reactor is more convenient to line with other materials and easy to process; different materials have larger corrosion resistance degree difference in the fluorination reaction, and the selectivity of the corrosion-resistant materials is more under the same equipment cost; is favorable for solving the corrosion problem in liquid phase fluorination.

The apparatus of the present invention is compared to prior art apparatus by synthesizing specific fluorinated alkanes.

Preparation of difluoromethane chloride:

in the device, trichloromethane and antimony pentachloride are mixed according to the mass ratio of 5:1, preheated to 50 ℃ at the flow rate of 1m/s, hydrogen fluoride is preheated to 70 ℃ at the flow rate of 0.5m/s, and the mixture enters a tubular reactor with the volume of 0.2L after being mixed by a static mixer. The tubular reactor is provided with three reaction sections, the temperature of the first reaction section is controlled to be 80 ℃, pressurized gas nitrogen is filled until the fluorination reaction pressure is controlled to be 1.0MPa, hydrogen fluoride and trichloromethane in raw material flows are subjected to fluorination reaction in the tubular reactor under the catalysis of a catalyst, the generated reaction liquid comprises a product of the fluorination reaction, namely difluorochloromethane, and also comprises unreacted raw materials and the catalyst, a gas-liquid separator is connected between the reaction sections of the tubular reactor, and the gas-phase product enters a deacidification device after being separated; and (2) feeding the separated liquid phase product into the next reaction section, supplementing hydrogen fluoride into the next reaction section at the flow rate of 0.25m/s, controlling the temperature of the subsequent reaction section to be 80 ℃, carrying out fluorination reaction on unreacted raw materials in the reaction liquid in the tubular reactor under the action of a catalyst, after the reaction is finished, allowing the generated reaction liquid to flow to a pressure stabilizing tank, separating the materials in the pressure stabilizing tank into a gas phase material containing the difluoromonochloromethane and a liquid phase material containing the unreacted raw materials, circulating the liquid phase material, separating the liquid phase material into a premixing tank and a hydrogen fluoride storage tank, allowing the gas phase material to pass through a separation device, performing related water washing, alkali washing, drying and rectification by using a water washing device, an alkali washing device, a drying device and a rectification device to obtain the difluoromonochloromethane product, and filling the difluoromonochloromethane product into a difluoromonochloromethane product storage tank for storage.

TABLE 1 analysis of the composition of the product difluoromethane monochloride prepared by the apparatus of the present invention

Name of component	Content (%)
		R23	0.0023
R22	99.9934
		R21	0.0025
CH2Cl2	0.0018
		H2O	0.0008

Preparation of difluoromethane:

in the device, dichloromethane and antimony pentachloride are mixed according to the mass ratio of 5:1, preheated to 60 ℃ at the flow rate of 1m/s, hydrogen fluoride is preheated to 80 ℃ at the flow rate of 0.5m/s, and the mixture enters a tubular reactor with the volume of 0.2L after being mixed by a static mixer. The tubular reactor is provided with three reaction sections, the temperature of the first reaction section is controlled to be 80 ℃, pressurized gas nitrogen is filled until the fluorination reaction pressure is controlled to be 2.5MPa, the fluorination reaction is carried out in the tubular reactor under the catalysis of a catalyst by hydrogen fluoride and dichloromethane in the material flow, and the generated reaction liquid comprises difluoromethane, an intermediate product, hydrogen chloride, unreacted raw materials and the catalyst which are products of the fluorination reaction; separating by a gas-liquid separator, feeding the gas-phase product into a deacidification device, and feeding the liquid-phase product into a second reaction section; and adding hydrogen fluoride into the second reaction section at the flow rate of 0.5m/s, controlling the temperature of the second reaction section to be 90 ℃, and carrying out fluorination reaction on unreacted raw materials in the reaction liquid in the tubular reactor under the action of a catalyst. Separating the reaction product by a gas-liquid separator, separating the gas-phase product, then feeding the gas-phase product into a deacidification device, and feeding the liquid-phase product obtained by separation into a third reaction section; hydrogen fluoride is supplemented to the third reaction section at the flow rate of 0.25m/s, and the temperature of the third reaction section is controlled to be 110 ℃; and (2) flowing the reaction liquid generated after the reaction to a pressure stabilizing tank, separating the material in the pressure stabilizing tank into a gas phase material containing difluoromethane and a liquid phase material containing unreacted raw materials, circulating the liquid phase material, separating the liquid phase material to a premixing tank and a hydrogen fluoride storage tank, passing the gas phase material through a separation device, performing related water washing, alkali washing, drying and rectification by the separation device comprising a water washing device, an alkali washing device, a drying device and a rectification device to obtain the product difluoromethane, and filling the product difluoromethane into a difluoromethane product storage tank for storage.

TABLE 2 compositional analysis of difluoromethane, a product prepared by the apparatus of the present invention

Preparation of 1, 1, 1, 3, 3-pentafluoropropane:

in the device, 1, 1, 1, 3, 3-pentachloropropane and antimony pentachloride are mixed according to the mass ratio of 5:1, preheated to 60 ℃ at the flow rate of 1m/s, hydrogen fluoride is preheated to 80 ℃ at the flow rate of 0.5m/s, and the mixture enters a tubular reactor with the volume of 0.2L after being mixed by a static mixer. The tubular reactor is provided with three reaction sections, the temperature of the first reaction section is controlled to be 80 ℃, pressurized gas nitrogen is filled until the fluorination reaction pressure is controlled to be 1.3MPa, the fluorination reaction is carried out in the tubular reactor under the catalysis of a catalyst by hydrogen fluoride and 1, 1, 1, 3, 3-pentachloropropane in the material flow, and the generated reaction liquid comprises products of the fluorination reaction, namely 1, 1, 1, 3, 3-pentafluoropropane, intermediate products, hydrogen chloride, unreacted raw materials and the catalyst; after pre-separation by a gas-liquid separator, a gas-phase product enters a deacidification device, and a liquid-phase product enters the next reaction section; adding hydrogen fluoride into the second reaction section at the flow rate of 0.5m/s, controlling the temperature of the subsequent second reaction section to be 100 ℃, and carrying out fluorination reaction on unreacted raw materials in the reaction liquid in the tubular reactor under the action of a catalyst; after the reaction product is pre-separated by a gas-liquid separator, the gas-phase product enters a deacidification device, and the liquid-phase product enters a third reaction section; controlling the temperature of the third reaction section to be 120 ℃, and supplementing hydrogen fluoride to the third reaction section at the flow speed of 0.25 m/s; after the reaction is finished, the generated reaction liquid flows to a surge tank, materials in the surge tank are separated into a gas-phase product containing 1, 1, 1, 3, 3-pentafluoropropane and a liquid-phase material containing unreacted raw materials, the liquid-phase material is circulated and then separated into a premixing tank and a hydrogen fluoride storage tank, the gas-phase product passes through a separation device, the separation device comprises a water washing device, an alkali washing device, a drying device and a rectifying device to carry out relevant water washing, alkali washing, drying and rectifying to obtain a product 1, 1, 1, 3, 3-pentafluoropropane, and the product 1, 1, 1, 3, 3-pentafluoropropane is filled into a product storage tank for storage.

TABLE 3 compositional analysis of 1, 1, 1, 3, 3-pentafluoropropane, a product prepared by the apparatus of the present invention

Name of component	Content (%)
		R235	0.0005
R245	99.9875
		R244	0.0078
R243	0.0035
		R242	0.0007
H2O	0.0007

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.