102 results about "Phosphorus trifluoride" patented technology

The invention discloses a preparation method and a production system of phosphorus trifluoride, and belongs to the technical field of preparation of phosphorus trifluoride. Phosphorus trichloride and first mixed gas are continuously introduced into a reactor, the first mixed gas comprises anhydrous hydrogen fluoride and inert gas, phosphorus trichloride and anhydrous hydrogen fluoride in the first mixed gas are subjected to a double decomposition reaction in the reactor, and intermediate gas containing phosphorus trifluoride is generated. Collecting intermediate gas discharged from the reactor, and rectifying and purifying the intermediate gas to obtain a phosphorus trifluoride product. The inert gas carries anhydrous hydrogen fluoride and phosphorus trichloride to generate double decomposition reaction to generate phosphorus trifluoride, and the inert gas can dilute the concentration of the raw material gas anhydrous hydrogen fluoride participating in the reaction and also can take away heat generated by the reaction, so that the temperature of the reactor is more stable, and continuous production of phosphorus trifluoride is realized.

The invention belongs to the technical field of preparation of phosphorus trichloride, and particularly relates to a preparation device and method of phosphorus trifluoride. The device comprises a reactor, a cold trap and a collector, the upper part of the reactor is provided with a phosphorus trichloride dropping device and a zinc fluoride feeding port, the upper end of the reactor is provided with a stirring paddle, the stirring paddle extends to the bottom of the reactor, the upper end of the reactor is communicated with the cold trap through a first pipeline, the pipeline is provided with a condensation pipe, and the condensation pipe is communicated with the cold trap through a second pipeline. The bottom of the cold trap is communicated with the reactor through a second pipeline; and the upper end of the cold trap is communicated with the collector through a third pipeline. The method comprises the following steps: dropwise adding phosphorus trichloride into anhydrous zinc fluoride powder in a nitrogen atmosphere, and stirring for reaction; and collecting a reaction product, and recovering phosphorus trichloride. By adding the stirring paddle into the reactor and adopting a two-stage condensation method, the conversion rate of the raw materials is increased, the production cost is reduced, and the operation process is simple.

The invention discloses a purification process of phosphorus trifluoride. The purification process comprises the following steps: S1, heating liquid in a first storage tank, and pumping the heated liquid into a flash evaporator for flash evaporation; s2, introducing the flashed gas into a first rectifying tower for rectification, condensing the rectified top products phosphorus trifluoride and hydrogen chloride, and introducing the condensed top products into an intermediate first product storage tank; s3, pumping the material in the middle first product storage tank into a second rectifying tower for rectification, condensing the top gas rectified by the second rectifying tower, and introducing the condensed gas into the first product storage tank for storage; s4, a finished product in the first product storage tank is pumped into a gasifier to be gasified and enters a gas-liquid separation tank to be separated, and separated gas is discharged from the top and sequentially introduced into three phosphorus trifluoride purification devices to be purified; s5, the purified gas is introduced into a filter to be filtered, the filtered gas enters a filling system to be filled after pressure stabilization, impurities in phosphorus trifluoride can be completely removed, and the purity of phosphorus trifluoride is improved in a jumping mode.

The invention discloses a phosphorus trifluoride production device and method, and belongs to the technical field of phosphorus trifluoride production, the device comprises a reaction part, a pretreatment part and a post-treatment part, the reaction part comprises a first raw material tank, a second raw material tank, a reaction kettle and a collection cold trap, the pretreatment part comprises a primary separation tower and an absorption tower, and the post-treatment part comprises a secondary separation tower and an absorption tower. The post-treatment part comprises an adsorption tower, a light component removal tower and a heavy component removal tower; the production method comprises the following steps: adding raw materials of phosphorus trichloride and hydrogen fluoride into a reaction kettle to generate phosphorus trifluoride and hydrogen chloride, collecting the phosphorus trifluoride and hydrogen chloride in a collecting cold trap, heating the collecting cold trap to vaporize the phosphorus trifluoride and hydrogen chloride, and sequentially entering a primary separation tower, a light component removal tower and a heavy component removal tower for a series of treatment, and finally, high-purity phosphorus trifluoride gas is extracted from the heavy component removal tower to a filling system. According to the method, high-purity phosphorus trifluoride with the purity larger than or equal to 99.999% can be finally produced, and the problem that in the prior art, the purity of phosphorus trifluoride is not enough is solved.

The invention relates to the technical field of chemical preparation, in particular to a preparation method of phosphorus trifluoride, which comprises the following steps: step 1, preparing reactants: preparing phosphorus pentoxide and pure fluorine gas; 2, mixing reactants: in a proper reaction container, mixing phosphorus pentoxide with pure fluorine gas; step 3, controlling the reaction conditions of reactants: ensuring that the reaction is carried out at proper temperature and pressure so as to promote the smooth proceeding of the reaction; and 4, separating the product to obtain phosphorus trifluoride. The method comprises the following steps: putting phosphorus pentoxide into a dry container, preparing a storage tank filled with fluorine gas, putting the prepared phosphorus pentoxide into a reaction container, introducing the dry fluorine gas from the storage tank, carrying out a reaction at high temperature and high pressure, and after the reaction is completed, adding the fluorine gas into the reaction container, phosphorus trifluoride and a byproduct oxyfluoride are separated through a physical method (distillation or condensation), so that the process is simple, and the reaction conversion rate is high.

The invention discloses a preparation method of phosphorus trifluoride. The preparation method comprises the following steps: S1, respectively adding phosphorus trichloride and anhydrous hydrogen fluoride into a uniform-temperature material changing structure of a reaction kettle; s2, condensing the crude phosphorus trifluoride gas, introducing the condensed crude phosphorus trifluoride gas into a first storage tank for storage, heating liquid in the first storage tank, and pumping the heated liquid into a flash evaporator for flash evaporation; s3, introducing the gas subjected to flash evaporation into a first rectifying tower for rectification, and introducing a product into an intermediate first product storage tank; s4, rectifying the material in the middle first product storage tank, condensing the rectified gas, and introducing the condensed gas into the first product storage tank for storage; s5, gasifying the finished product in the first product storage tank, enabling the gasified finished product to enter a gas-liquid separation tank for separation, discharging separated gas from the top, and sequentially introducing the separated gas into three phosphorus trifluoride purification devices for purification; s6, the purified gas is introduced into a filter to be filtered, the filtered gas enters a filling system to be filled after the pressure of the filtered gas is stabilized, and the stability of the product and the safety of equipment are guaranteed.

The invention discloses preparation equipment and a preparation method of high-purity phosphorus trifluoride, the preparation equipment comprises a micro-channel reactor, the micro-channel reactor comprises a plurality of reaction modules, each reaction module comprises a first reaction cavity arranged on the side surface of a fixed substrate in a convex manner, and the other side surface of the fixed substrate is provided with a plurality of second reaction cavities in a convex manner; a material guide hole for communicating the first reaction cavity with the second reaction cavity is formed in the fixed base plate; a feeding hole is formed in the fixed base plate, and the feeding hole is outwards connected with a corresponding three-way feeding pipe; a discharging hole is formed in the fixed base plate, and the discharging hole is outwards connected with a corresponding discharging pipe; and the condenser comprises a condensation cylinder, the two ends of the condensation cylinder are fixedly connected with sealing plates, the top of the condensation cylinder is upwards connected with a pre-cooling cylinder, the top of the pre-cooling cylinder is closed, and the discharging pipe is connected to the top of the pre-cooling cylinder in parallel. The production efficiency can be improved, and the quality stability of products can be ensured.

A method for producing phosphorus trifluoride and a method for producing phosphorus pentafluoride, which have high reaction efficiency, low reaction temperature and an excellent energy efficiency. The method includes: a step of introducing phosphorus trichloride and hydrogen fluoride into a first reactor, and a step of discharging phosphorus trifluoride from the first reactor, the first reactor contains carbon material. The method includes a step of introducing the phosphorus trifluoride obtained above and chlorine into a second reactor, and a step of discharging dichloro-phosphorus trifluoride from the second reactor. The method further includes a step of introducing the dichloro-phosphorus trifluoride obtained above and hydrogen fluoride into a third reactor; and a step of discharging phosphorus pentafluoride from the third reactor. The method further includes a step of introducing the phosphorus pentafluoride obtained above and lithium fluoride into a fourth reactor; and a step of discharging lithium hexafluorophosphate from the fourth reactor.

The invention belongs to the technical field of fluorine chemical material preparation, and particularly relates to a method for continuously preparing phosphorus trifluoride based on liquid-liquid microfluidics. The method comprises the following steps: mixing AHF liquid with an excessive PC13 liquid material in a spherical liquid drop form, introducing the mixture into a spiral tube microreactor, controlling the pressure in the spiral tube microreactor to be 1.0-2.5 MPa and the temperature to be 60-140 DEG C, carrying out reaction, carrying out reduced pressure gas-liquid separation on the reacted material, and separating and purifying a gas-phase component to obtain phosphorus trifluoride, and the liquid-phase component enters the spiral tube microreactor as a PC13 liquid feed cycle to participate in the reaction. According to the invention, efficient, safe and continuous preparation of phosphorus trifluoride is realized through an innovative liquid-liquid microfluidic technology.

The invention discloses a production method and a production system of high-purity phosphorus trifluoride and hydrogen chloride, and belongs to the field of preparation of phosphorus trifluoride and hydrogen chloride. The production method comprises the following steps: reacting phosphorus trichloride with anhydrous hydrogen fluoride to generate phosphorus trifluoride and hydrogen chloride, condensing at-20 DEG C to 0 DEG C, refluxing phosphorus trichloride and hydrogen fluoride raw materials, and outputting mixed gas of phosphorus trifluoride and hydrogen chloride; preliminarily rectifying the mixed gas to obtain a phosphorus trifluoride crude product and a hydrogen chloride crude product; the method comprises the following steps: carrying out primary rectification on a phosphorus trifluoride crude product in a phosphorus trifluoride rectification heavy component removal tower and carrying out secondary rectification in a phosphorus trifluoride rectification light component removal tower in sequence to obtain high-purity phosphorus trifluoride gas; the crude hydrogen chloride is subjected to primary rectification in a hydrogen chloride rectification heavy component removal tower and secondary rectification in a hydrogen chloride rectification light component removal tower in sequence, and high-purity hydrogen chloride gas is obtained. According to the production method, high-purity phosphorus trifluoride and high-purity hydrogen chloride can be continuously produced and obtained, meanwhile, the raw material utilization rate can be increased, the product yield can be increased, meanwhile, little waste gas is generated, the waste gas can be completely absorbed, and the requirement for environmental protection is met.

The invention relates to a secondary fluorination system for synthesizing PF3. The secondary fluorination system comprises a main reactor, a condenser pipe, a secondary fluorination reactor and a cold trap, the invention also discloses a secondary fluorination process for synthesizing PF3, which comprises the following steps: introducing gas-phase HF into a liquid-phase PC13 raw material to generate gas-phase main products PF3 and HCl and a small amount of by-product fluorine chloride, carrying out secondary fluorination reaction on the products through a fluorinating agent ZnF2, almost completely converting the by-products into the target product PF3, and collecting the final product in a cold trap. According to the invention, the content of by-products in the cold trap is greatly reduced, the conversion rate of raw materials is improved, and the purification efficiency of the crude phosphorus trifluoride is improved.

The present invention discloses a phosphorus trifluoride purification device, comprising an adsorption tower body, an upper cover, a plurality of air inlet ends, and an air outlet end, and further comprising: a double-position sliding molecular sieve structure, comprising a first molecular sieve adsorption cylinder and a second molecular sieve adsorption cylinder; a pressure variable diameter adjustment structure arranged between the first molecular sieve adsorption cylinder and the second molecular sieve adsorption cylinder, the pressure variable diameter adjustment structure comprising an elastic adjustment component arranged on the inner wall of the adsorption tower body, the upper and lower ends of the elastic adjustment component being respectively connected to the first molecular sieve adsorption cylinder and the second molecular sieve adsorption cylinder, a pressure adjustment disk being connected to the middle part of the elastic adjustment component, the pressure adjustment disk being provided with a plurality of holes for phosphorus trifluoride to pass through, the holes being provided with internal barrier structures, and a top bone component being fixedly provided on the top of the first molecular sieve adsorption cylinder. The present invention maximizes the extension of the service life of the adsorption structure while ensuring adsorption efficiency.

The invention provides a phosphorus trifluoride production system and a preparation method thereof, and belongs to the technical field of phosphorus trifluoride manufacturing. The phosphorus trifluoride production system comprises a static reactor, a gaseous fluorine source, a liquid phosphorus source, a condenser and a collector. The static reactor comprises a static mixer and a jacket type shell wrapping the static mixer, the static mixer is used for mixing reaction raw materials and providing a reaction place, and a heat exchange cavity used for containing a heat exchange medium is formed in the jacket type shell; when the production system is used for preparing phosphorus trifluoride, the problems that the mass transfer effect between a gaseous fluorine source and a liquid phosphorus source is poor and the material distribution uniformity is poor can be effectively solved, and meanwhile, the whole material system can have better temperature consistency, so that the reaction raw materials can react more efficiently and thoroughly to form phosphorus trifluoride.

The application belongs to the field of organic phosphorus chemistry and phosphorus chemical industry, and particularly relates to a preparation method of phosphorus trifluoride, comprising the following steps: under the protection of inert gas, reacting phosphorus trichloride with an ionic liquid to obtain phosphorus trifluoride. The application uses the ionic liquid as a fluorine source, avoids using dangerous raw materials such as hydrogen fluoride and metal fluoride, and the ionic liquid can not only be used as a fluorine source, but also as a reaction solvent, so that the reaction activity of phosphorus trichloride and the ionic liquid is greatly improved. The application has mild reaction conditions, low reaction temperature, short reaction time, and the reaction system does not produce other byproduct gases, the post-processing operation is simple, and the reaction yield and purity are high.

The invention discloses a preparation method for continuous production of phosphorus trifluoride, and belongs to the technical field of chemical synthesis, and the key point of the technical scheme is that the preparation method for continuous production of phosphorus trifluoride comprises the following preparation steps: S1, adding phosphorus trichloride into the upper part of a rectifying tower, adding anhydrous hydrogen fluoride gas into the lower part of the rectifying tower, and stirring; contacting the two raw materials on the surface of the rectifying tower filler to complete reaction; s2, a product obtained through reaction is discharged from the top of the rectifying tower and enters a purification system, and phosphorus trifluoride is obtained.When phosphorus trifluoride is prepared through the rectifying method, the reaction process is stable, the temperature is easy to control, the gas-liquid contact area is large, the reaction is complete, the reaction speed is high, and large-batch production is facilitated.

The purpose of the present invention is to provide a production method for phosphorus trifluoride in which the reaction can be carried out using readily available materials at a temperature equal to or lower than atmospheric temperature, said method being suitable for use on an industrial scale.　The production method for phosphorus trifluoride involves reacting phosphorus trichloride and hydrogen fluoride in the presence of an organic solvent.

The present invention produces phosphorus trifluoride at a high yield by using readily available raw materials (phosphorus trichloride and hydrogen fluoride), and produces a high-purity phosphorus trifluoride by purifying an obtained product gas containing phosphorus trifluoride by using a method suitable for mass production.　The present invention pertains to: a method for producing phosphorus trifluoride, the method comprising (a) a step for reacting phosphorus trichloride with hydrogen fluoride to produce a product gas, and (b) a step for removing hydrogen chloride from the product gas; and a high-purity phosphorus trifluoride obtained by said method.

The present invention discloses a filter for preparing phosphorus trifluoride, comprising: a fixed cylinder with closed ends, one end of the fixed cylinder being upwardly provided with a feed pipe and the other end being downwardly connected to a discharge pipe; a filtering mechanism comprising a first sealed bearing and a second sealed bearing fixedly connected to the fixed cylinder, the first sealed bearing and the second sealed bearing being respectively fixedly connected to corresponding fixed ring plates, a baffle being sealed and fixedly connected to the fixed ring plate mounted on the first sealed bearing, and corresponding filter plates being fixedly connected in a serrated shape between the fixed ring plates; a dust removal mechanism comprising a dust removal notch, the bottom of the fixed cylinder outside the dust removal notch being downwardly connected to a dust removal pipe, the outer end of the filter plate being fixedly connected to a spiral dust removal plate; and a driving mechanism for driving the baffle to rotate. The present invention can effectively discharge and collect filtered particulate matter without disassembling the filter, and can effectively improve the overall structural stability of the filtering mechanism.

The invention relates to the technical field of gas chromatography determination, and discloses a phosphorus trifluoride impurity component analysis system and method.The phosphorus trifluoride impurity component analysis system comprises a first sampling device, a second sampling device and a third sampling device, the second sampling device is used for randomly taking out quantitative gas from phosphorus trifluoride to be detected as a second sample; the first detection assembly is used for detecting the concentration of a first impurity component in the first sample; the second detection assembly is used for detecting the concentration of a second impurity component in the second sample; and the gas pipeline is used for conveying gas. According to the invention, various impurity gases can be detected, the purpose of comprehensively analyzing impurity components in phosphorus trifluoride is achieved, and the accuracy of phosphorus trifluoride purity detection is improved.

The application discloses a fluorination system and process for synthesizing high-purity phosphorus trifluoride, and the core innovation point of the application is that the bottleneck of the prior art is broken through by means of the synergistic design of solvent system optimization, dispersion pump strengthening, secondary fluorination deepening and composite adsorption refining. The process comprises the following steps: system pretreatment, raw material feeding and preheating, primary reaction and process control, secondary deepening fluorination, composite adsorption refining, product collection and semi-continuous circulation. By optimizing the solvent system, strengthening the dispersion mass transfer, deepening the secondary fluorination and the composite adsorption refining, the purity and yield of the phosphorus trifluoride can be significantly improved, the impurity content is reduced, semi-continuous production is realized, and the process has a good industrial application prospect.

The application discloses a kind of phosphorus trifluoride sample analysis sampling systems, comprising: sample inlet pipe is connected to storage steel bottle, and the discharge end is equipped with feed valve;Nitrogen replacement pipe is connected to the discharge end of feed valve in parallel;Fixed pipe, one end is connected to the discharge end of feed valve, and the other end is connected with sample discharge pipe downward;Filter, including first sealing bearing and second sealing bearing with fixed ring plate, the fixed ring plate on first sealing bearing is sealed with baffle, corresponding filter plate is fixed between fixed ring plate in zigzag shape;Dust removal mechanism, including dust removal gap arranged at the bottom side of the outer ring of first sealing bearing, the bottom of fixed pipe is connected with dust removal pipe downward, and the outer end of filter plate is fixed with spiral dust removal plate;Driving mechanism is used to drive baffle to rotate.The application can safely and conveniently sample phosphorus trifluoride, and send sample to corresponding detection instrument for analysis, and can effectively ensure sampling analysis precision.

The invention discloses a phosphorus trifluoride sample analyzing and sampling system, which comprises: a sample introduction pipe connected to a storage steel cylinder, the discharge end of which is provided with a feed valve; the nitrogen replacement pipe is connected to the discharging end of the feeding valve in parallel; one end of the fixed pipe is connected to the discharging end of the feeding valve, and the other end of the fixed pipe is downwards connected with a sample discharging pipe; the filter comprises a first sealing bearing and a second sealing bearing which are fixedly connected with fixed ring plates, the fixed ring plates on the first sealing bearing are fixedly connected with baffles in a sealing manner, and corresponding filter plates are fixedly connected between the fixed ring plates in a zigzag manner; the dust removal mechanism comprises a dust removal notch formed in the bottom side of the outer ring of the first sealing bearing, the bottom of a fixed pipe is downwards connected with a dust removal pipe, and the outer end of a filter plate is fixedly connected with a spiral dust removal plate; and the driving mechanism is used for driving the baffle to rotate. According to the phosphorus trifluoride sampling device, phosphorus trifluoride can be safely and conveniently sampled and sent to a corresponding detection instrument for analysis, and the sampling analysis precision can be effectively ensured.

The invention discloses a phosphorus trifluoride filter, comprising an outer shell, a filter element shell, and further comprising: a reciprocating recoil assembly, comprising a rocking piece and a guide seat, wherein when a fluid is introduced into the filter element shell, the filter element shell is squeezed toward the rocking piece on one side of the fluid flow direction, and when the fluid is cut off, the filter element shell swings left and right under the action of the rocking piece; a multi-baffle filter element structure, which is arranged in the filter element shell, the filter element shell is a diamond structure, and the multi-baffle filter element structure comprises a first feed filter, a first filter ring plate, a second feed filter cartridge, an outer ring baffle, a second closing plate, a second filter ring plate, and a retention frame; an outer bottom extraction structure, wherein a plurality of horizontal connecting frames are arranged at intervals at the lower end of the diamond structure, and the outer bottom extraction structure comprises a fixing seat, a plurality of elastic tubes, and a plurality of quick connectors. The invention cleans the filter membrane or the filter plate immediately after a single filtration, thereby improving the service life of the filter membrane or the filter plate and the filtration quality.

The present invention provides a method for preparing phosphorus trifluoride, comprising the steps of mixing a phosphorus triiodide organic solution with a metal fluoride salt, and reacting until no bubbles are generated to obtain phosphorus trifluoride; the metal fluoride salt comprises any one of sodium fluoride, potassium fluoride, or aluminum fluoride, or a combination of at least two. The method is simple to operate and, by selecting a suitable metal fluoride salt, produces a phosphorus trifluoride product with stable quality, high purity, and low impurities, making it suitable for industrial production of high-purity phosphorus trifluoride.

An apparatus for purifying high-purity phosphorus trifluoride according to one embodiment of the present invention comprises: a phosphorus trifluoride production unit including a reactor in which a phosphorus chloride compound solution and a metal fluoride salt react, and a purge device for vacuum-purging the reactor; a first freezing unit for cooling a phosphorus trifluoride mixed gas obtained from the phosphorus trifluoride production unit to remove unreacted materials contained in the phosphorus trifluoride mixed gas; and a second freezing unit for cooling the phosphorus trifluoride mixed gas obtained from the first freezing unit with liquid nitrogen to remove purge gas and hydrogen chloride (HCl).

The application belongs to the technical field of fluorinated material preparation, and particularly relates to a device and method for continuously preparing phosphorus trifluoride based on gas-liquid microfluidics. The device comprises a gas-liquid distributor, a spiral tube microreactor and a gas-liquid condensation separation tank connected in sequence. The gas-liquid distributor is a coaxial sleeve type gas-liquid distributor, the inner sleeve forms a central gas channel, and the annular liquid channel is formed between the outer sleeve and the inner sleeve. The preparation method is as follows: AHF gas is delivered to the central gas channel, and PCl3 liquid is delivered to the annular liquid channel at the same time. After the axial mixing of the AHF gas and the PCl3 liquid at the end of the gas-liquid distributor, the mixture enters the spiral tube microreactor to form a circular flow for reaction. The product after the reaction enters the gas-liquid condensation separation tank for cooling, separation and purification, and phosphorus trifluoride is obtained. The reaction device and method have the advantages of high efficiency, safety, environmental protection and economy.

A method for producing phosphorus trifluoride by reacting a metal fluoride, a phosphorus chloride compound, and a solvent according to the present invention uses a continuous production device including a screw reactor to produce phosphorus trifluoride, and thus can continuously mass-produce high-purity phosphorus trifluoride, has excellent selectivity for phosphorus trifluoride, and can reduce production costs and energy, thus being economical.

The method for preparing phosphorous trifluoride according to the present invention comprises the steps of: controlling the particle size (D50) of NaF to 67 μm to 137 μm; and reacting the particle size-controlled NaF, PCl3, and a solvent to prepare phosphorus trifluoride. By maximizing reactivity through control of the NaF particle size, the conversion rate of NaF can be increased, thereby suppressing the generation of unreacted NaF. Further, the selectivity for phosphorus trifluoride is excellent, and the preparation cost can be reduced.

The invention discloses a method for co-producing high-purity hydrogen chloride from electronic-grade phosphorus trifluoride, which comprises the following steps: by taking phosphorus trichloride and hydrogen fluoride as raw materials, firstly pressurizing and feeding the phosphorus trichloride to a reaction rectifying tower kettle, then slowly introducing anhydrous hydrogen fluoride gasified by a vaporizer into the reaction rectifying tower kettle, and slowly reacting while maintaining the tower kettle temperature at a certain temperature; the generated hydrogen chloride and phosphorus trifluoride are discharged from the top of the reactive distillation tower and sent to a pre-separation tower, heavy components such as H2O are thrown out from a tower kettle, the hydrogen chloride and the phosphorus trifluoride are separated through the pre-separation tower, and then the hydrogen chloride and the phosphorus trifluoride enter a heavy component removal tower and a light component removal tower respectively and are further purified to obtain electronic-grade phosphorus trifluoride and high-purity hydrogen chloride products.

The invention discloses phosphorus trifluoride purification equipment, which comprises an adsorption tower body, an upper cover, a plurality of gas inlet ends and a gas outlet end, and also comprises a double-position sliding molecular sieve structure, which comprises a first molecular sieve adsorption cylinder and a second molecular sieve adsorption cylinder; the pressure variable-diameter adjusting structure is arranged between the first molecular sieve adsorption cylinder and the second molecular sieve adsorption cylinder and comprises an elastic adjusting assembly arranged on the inner side wall of the adsorption tower body, and the upper end and the lower end of the elastic adjusting assembly are connected to the first molecular sieve adsorption cylinder and the second molecular sieve adsorption cylinder respectively; a pressure adjusting disc is connected to the middle of the elastic adjusting assembly, a plurality of holes allowing chlorine trifluoride to pass through are formed in the pressure adjusting disc, inner blocking structures are arranged in the holes, and a top rib assembly is fixedly arranged at the top of the first molecular sieve adsorption cylinder. And the service cycle of the adsorption structure is prolonged to the maximum extent.