CN216890735U

CN216890735U - Device for industrial production of trifluoromethyl hypofluorite

Info

Publication number: CN216890735U
Application number: CN202121382330.3U
Authority: CN
Inventors: 郭澎湃; 刘波; 彭涛; 李慧; 宋亦兰; 王亚宁
Original assignee: Zhonghao Chenguang Research Institute of Chemical Industry Co Ltd
Current assignee: Zhonghao Chenguang Research Institute of Chemical Industry Co Ltd
Priority date: 2021-06-21
Filing date: 2021-06-21
Publication date: 2022-07-05
Anticipated expiration: 2031-06-21

Abstract

The utility model provides a device for industrially producing trifluoromethyl hypofluorite. The device for industrially producing the trifluoromethyl hypofluorite comprises a first reactor, a second reactor, a collector, a pressure pump and a gas holder which are sequentially connected into a closed circuit. The waste gas discharged from the collector is used as the raw material of the trifluoromethyl hypofluorite and is introduced into the reaction system for reutilization, so that the loss caused by directly discharging the waste gas out of the tail gas treatment device is reduced, the pressure of the tail gas treatment device and the risk of environmental pollution are reduced, the product yield is improved, the production cost is reduced, and the method has good industrial application value.

Description

Device for industrial production of trifluoromethyl hypofluorite

Technical Field

The utility model relates to the technical field of fluorine-containing intermediate production, in particular to a device for industrially producing trifluoromethyl hypofluorite.

Background

With the continuous development of fluorine-containing fine chemicals at home and abroad, trifluoromethyl hypofluorite (CF)₃OF) is widely used in the synthesis OF fluorine-containing and perfluorinated monomers as fluorine-containing intermediates, such as perfluoromethylethyl ether, trifluoromethylethyl ether, trifluoromethylmethyl ether, and the like. In the production of trifluoromethylhypofluorite from CO and fluorine gas, the fluorine gas does not react completely, the collected gas contains 3 to 5% fluorine gas, and the activity of the fluorine gas is very strong, so that CF as an intermediate₃The fluorine gas in OF must be reduced to 1% or less.

Application No. 89104118.4 provides a process for the preparation of fluoroxytrifluoromethane by catalytic fluorination of a product which does not contain F₂Can be directly used for requiring CF without any separation₃OF is free OF F₂In the case of (1). However, in this method, the catalyst used in the two-stage catalytic reactor needs to be repeatedly activated, the process is complicated, and in addition, the obtained CF₃The OF content only reaches 78-85%, and the purity is low.

The method currently used industrially collects reaction gas including trifluoromethylhypofluorite, fluorine gas, fluorophosphates, carbon tetrafluoride, bis-trifluoromethylperoxide at low temperature using liquid nitrogen, and then purifies the trifluoromethylhypofluorite by exhausting gas a plurality of times so that the fluorine gas content is controlled to be less than 1%, but about 40% of the trifluoromethylhypofluorite is lost during the exhaust gas purification. In addition, the material gas is special, so that the reaction gas cannot be physically rectified and purified.

SUMMERY OF THE UTILITY MODEL

Aiming at the defects in the prior art, the utility model provides a device for industrially producing trifluoromethyl hypofluorite, which leads the waste gas discharged from a collector as the raw material of the trifluoromethyl hypofluorite into a reaction system for reutilization, thereby not only reducing the loss caused by directly discharging the waste gas out of a tail gas treatment device, but also reducing the pressure of the tail gas treatment device and the risk of environmental pollution, simultaneously improving the product yield, reducing the production cost and having good industrial application value.

The utility model provides the following technical scheme:

an apparatus for industrially producing trifluoromethyl hypofluorite comprises a collector, a pressure pump, a gas holder, a first reactor and a second reactor which are sequentially connected into a closed circuit.

The device is described in detail below:

the collector comprises an outer cylinder and an inner cylinder, a jacket space is arranged between the outer cylinder and the inner cylinder, and liquid nitrogen is filled in the jacket space; the inner cylinder is made of metal. Wherein, liquid nitrogen is intermittently filled in the jacket space to provide cold energy for the reaction gas, and separation and purification of the trifluoromethyl hypofluorite in the reaction gas can be realized by controlling the temperature and the pressure in the collector (particularly controlling the temperature and the pressure in the inner cylinder of the collector). The inner cylinder made of metal material keeps good strength and performance in the repeated change process of ultralow temperature and normal temperature.

The pressure pump is fluorine-resistant and acid-resistant, and the acid comprises hydrofluoric acid, hydrochloric acid and the like. Thereby, the normal operation under the condition of containing fluorine gas is ensured.

The gas holder is made of metal, and the inner surface of the gas holder is subjected to oil removal and degreasing treatment before use. For example, the cleaning is performed with a detergent. Thus, the fluorine gas in the exhaust gas is prevented from reacting with the grease, and the recovery amount of the fluorine gas is reduced.

The working principle of the device for industrially producing the trifluoromethyl hypofluorite is as follows:

fluorine gas and CO generate fluorophosphates in a first reactor, the fluorophosphates and unreacted fluorine gas enter a second reactor to react under the catalysis of a nickel simple substance and under the high-temperature condition to obtain the fluorine-containing gas₂、CF₂O、CF₄、CF₃OOCF₃And CF₃And OF mixed gas. The mixed gas is separated and purified in the collector by controlling the temperature and the pressure of the collector, and the purified CF₃OF is concentrated in the collector, and the exhaust gas (containing F) is discharged from the collector₂、CF₂O、CF₄、CF₃OOCF₃And CF₃OF) is returned to the first reactor through a gas holder under the action OF a pressure pump and is recycled as a raw material.

The utility model also provides a method for industrially producing trifluoromethyl hypofluorite, which comprises the following steps:

1) fluorine gas and CO enter a second reactor after undergoing a first reaction in a first reactor, and undergo a second reaction under the action of a nickel simple substance to obtain a mixed gas;

2) the mixed gas enters a collector to carry out separation and purification of trifluoromethyl hypofluorite under the action of liquid nitrogen, and the discharged waste gas returns to the first reactor for recycling through a gas holder under the action of a pressurizing pump;

3) carbon tetrafluoride in the exhaust gas is accumulated continuously with the continuous recycling of the exhaust gas, and the exhaust gas is discharged to a tail gas treatment system when the mass concentration of the carbon tetrafluoride reaches a prescribed concentration.

In a preferred embodiment of the present invention, the molar ratio of fluorine gas to CO is (1.8 to 2.0): 1; the temperature of the first reaction is 60-120 ℃.

The temperature of the second reaction is 200-450 ℃.

Controlling the pressure in the collector to be 0-2.5 Mpa and the temperature to be-196 to-60 ℃.

And controlling the pressure of the gas holder to be 0-0.6 Mpa.

When the mass concentration of carbon tetrafluoride in the exhaust gas discharged from the collector exceeds 15%, the exhaust gas is discharged to an exhaust gas treatment system.

The beneficial effects of the utility model include:

according to the utility model, the waste gas discharged in the purification process of the collector is recovered, the fluorine-resistant gas pressure pump is transferred into the gas holder, and then the waste gas is introduced into the reaction device as the raw material for preparing the trifluoromethyl hypofluorite, so that the loss caused by directly discharging the waste gas to the tail gas treatment device in the prior art is reduced, the treatment pressure of the tail gas treatment device and the risk of environmental pollution are also reduced, and the production cost is reduced.

Drawings

FIG. 1 is a schematic structural diagram of an apparatus for industrially producing trifluoromethyl hypofluorite according to the present invention.

Detailed Description

The following examples are intended to illustrate the utility model but are not intended to limit the scope of the utility model.

Example 1

As shown in fig. 1, this example provides an apparatus for industrially producing trifluoromethyl hypofluorite, which includes: a reactor 4, a reactor 5, a collector 1, a booster pump 2 and a gas holder 3 which are connected in sequence to form a closed circuit.

The collector 1 comprises an outer cylinder and an inner cylinder (not shown in the figure), a jacket space is arranged between the outer cylinder and the inner cylinder, liquid nitrogen is filled in the jacket space, and the inner cylinder is made of metal materials.

The pressure pump is an acid-resistant and corrosion-resistant pressure pump.

The gas holder is made of metal, and the inner surface of the gas holder is subjected to oil removal and ester removal treatment in advance.

The embodiment provides a method for industrially producing trifluoromethyl hypofluorite, which comprises the following steps:

1) fluorine gas and CO enter a reactor 4 for reaction, and then enter a reactor 5 for reaction under the action of a nickel elementary substance catalyst, wherein the molar ratio of the fluorine gas to the CO is (1.8-2.0): 1, the temperature of a reactor 4 is 60-120 ℃, a reactor 5 is a fixed bed reactor loaded with a nickel elementary substance catalyst, and the temperature of the reactor 5 is 200-450 ℃;

2) intermittently filling liquid nitrogen into the jacket space of the collector 1, controlling the temperature of the inner cylinder of the collector 1 to be-196 ℃ to-60 ℃ and the pressure to be 0-2.5 Mpa, and allowing the mixed gas discharged from the reactor 5 to enter the collector 1 for CF₃OF separation and purification, CF separated from mixed gas₃OF is collected in a collector 1, and the discharged waste gas is stored in a gas holder 3 under the action OF a pressurizing pump 2 and then returns to a reactor 4 for recycling in the form OF raw materials; control theThe pressure of the gas holder is 0-0.6 Mpa;

3) and accumulating carbon tetrafluoride in the waste gas continuously along with the continuous recycling of the waste gas, and discharging the waste gas to a tail gas treatment system for treatment when the mass concentration of the carbon tetrafluoride in the waste gas discharged from the collector 1 exceeds 15%.

Example 2

This example serves to illustrate the effect of the method of the utility model.

Conditions 1 and 2 were both carried out using the method provided in example 1; the difference between the prior art and the example 1 is that the mixed gas discharged from the reactor 5 enters the collector 1 for CF₃And OF separation and purification, wherein the waste gas discharged from the collector 1 directly enters alkaline washing for evacuation without circulation.

The specific charge amounts and the reaction results are shown in Table 1.

TABLE 1

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; 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.

Claims

1. The device for industrially producing the trifluoromethyl hypofluorite is characterized by comprising a collector, a pressure pump, a gas holder, a first reactor and a second reactor which are sequentially connected into a closed circuit;

the collector comprises an outer cylinder and an inner cylinder, a jacket space is arranged between the outer cylinder and the inner cylinder, and liquid nitrogen is filled in the jacket space.

2. The apparatus for industrially producing trifluoromethyl hypofluorite according to claim 1, wherein the inner cylinder is made of metal.

3. The apparatus for industrially producing trifluoromethylhypofluorite according to claim 1, wherein the pressure pump is a fluorine gas-resistant and acid-resistant pressure pump.

4. The apparatus for industrially producing trifluoromethyl hypofluorite according to claim 1, wherein the gas holder is made of metal.

5. The apparatus for industrially producing trifluoromethyl hypofluorite according to claim 4, wherein the inner surface of the gas holder is preliminarily subjected to degreasing treatment.