Abstract: The invention is a method for continuously preparing highly pure octafluorocyclopentene for use in dry-etching processes. The method includes reacting octachlorocyclopentene with KF in a continuous manner, and purifying crude octafluorocyclopentene. In the reacting step, two KF-charged filters are installed in parallel and allowed to communicate with a reactor containing octachlorocyclopentene in an alternating manner to produce crude octafluorocyclopentene. In the purifying step, organics having lower boiling points than octafluorocyclopentene are removed, and metal ingredients and organics having boiling points higher than octafluorocyclopentene are separated to recover octafluorocyclopentene as a gas. The gaseous octafluorocyclopentene composition contains C5F8 in an amount of 99.995 vol % or higher, nitrogen in an amount of 50 vol ppm or less, oxygen in an amount of 5 vol ppm or less, water in an amount of 5 vol ppm or less, and metal ingredients in an amount of 5 wt ppb or less.

Abstract: The invention is a method for continuously preparing highly pure octafluorocyclopentene for use in dry-etching processes. The method includes reacting octachlorocyclopentene with KF in a continuous manner, and purifying crude octafluorocyclopentene. In the reacting step, two KF-charged filters are installed in parallel and allowed to communicate with a reactor containing octachlorocyclopentene in an alternating manner to produce crude octafluorocyclopentene. In the purifying step, organics having lower boiling points than octafluorocyclopentene are removed, and metal ingredients and organics having boiling points higher than octafluorocyclopentene are separated to recover octafluorocyclopentene as a gas. The gaseous octafluorocyclopentene composition contains C5F8 in an amount of 99.995 vol % or higher, nitrogen in an amount of 50 vol ppm or less, oxygen in an amount of 5 vol ppm or less, water in an amount of 5 vol ppm or less, and metal ingredients in an amount of 5 wt ppb or less.

Abstract: The invention is a method for continuously preparing highly pure octafluorocyclopentene for use in dry-etching processes. The method includes reacting octachlorocyclopentene with KF in a continuous manner, and purifying crude octafluorocyclopentene. In the reacting step, two KF-charged filters are installed in parallel and allowed to communicate with a reactor containing octachlorocyclopentene in an alternating manner to produce crude octafluorocyclopentene. In the purifying step, organics having lower boiling points than octafluorocyclopentene are removed, and metal ingredients and organics having boiling points higher than octafluorocyclopentene are separated to recover octafluorocyclopentene as a gas. The gaseous octafluorocyclopentene composition contains C5F8 in an amount of 99.995 vol % or higher, nitrogen in an amount of 50 vol ppm or less, oxygen in an amount of 5 vol ppm or less, water in an amount of 5 vol ppm or less, and metal ingredients in an amount of 5 wt ppb or less.

Abstract: The method of producing 4-fluoroethylene carbonate (FEC), in which ethylene carbonate (EC) reacts with a mixture of fluorine and nitrogen gases, includes feeding a mixture gas of fluorine gas and nitrogen gas into a reactor having ethylene carbonate charged therein, so as to react the ethylene carbonate with the mixture gas of the fluorine gas and the nitrogen gas. The mixture gas fed in the reactor is regulated to have a desired bubble size while passing through a gas bubble regulating column, in which a packing for a packed column is packed. In the method, EC directly reacts with F2/N2 mixture gas to produce FEC, thus a purification process is simple and it is possible to produce FEC at high conversion efficiency and selectivity.

Abstract: The method of preparing a chromium oxide catalyst for preparation of pentafluoroethane using a chloroethane compound includes heat treating chromium hydroxide powder at a temperature not higher than 300° C. to obtain chromium oxide powder, heat treating metal hydroxide, at a temperature not higher than 300° C. to obtain metal oxide powder, mixing 85˜99.5 wt % of the chromium oxide powder with 0.5˜15 wt % of the metal oxide powder to obtain a mixture, forming the mixture into a pellet, calcining the pellet at 200-300° C. using nitrogen gas, and fluorinating the pellet at 300-320° C. using a gas mixture including N2 and HF, and then at 320-380° C. using HF gas. The fluorination catalyst prepared using the method of this invention can be effectively used to prepare pentafluoroethane at a high yield using a chloroethane compound.

Abstract: The method of preparing a chromium oxide catalyst for preparation of pentafluoroethane using a chloroethane compound includes heat treating chromium hydroxide powder at a temperature not higher than 300° C. to obtain chromium oxide powder, heat treating metal hydroxide, at a temperature not higher than 300° C. to obtain metal oxide powder, mixing 85-99.5 wt % of the chromium oxide powder with 0.5-15 wt % of the metal oxide powder to obtain a mixture, forming the mixture into a pellet, calcining the pellet at 200-300° C. using nitrogen gas, and fluorinating the pellet at 300-320° C. using a gas mixture including N2 and HF, and then at 320-380° C. using HF gas. The fluorination catalyst prepared using the method of this invention can be effectively used to prepare pentafluoroethane at a high yield using a chloroethane compound.

Abstract: Disclosed is a method of charging a low temperature liquefied gas in a gaseous state in a high pressure charging cylinder using a pump. The method is advantageous in that it is possible to charge a low temperature liquefied gas which is to be made highly pure in a high pressure gas cylinder using a simple process in which purity is not changed and little energy is consumed during the charging of the liquefied gas.

Abstract: Disclosed is a method of charging a low temperature liquefied gas in a high pressure charging cylinder using a diaphragm pump. The method is advantageous in that it is possible to charge a low temperature liquefied gas which is to be made highly pure in a high pressure gas cylinder using a simple process in which the liquefied gas does not deteriorate and small energy is consumed.

Abstract: The method of storing nitrogen trifluoride includes storing nitrogen trifluoride in a chromium-molybdenum steel vessel manufactured through a deep drawing ironing process. Nitrogen trifluoride stored in this way according to the method of this invention does not deteriorate even after two years or more have passed.

Abstract: Disclosed herein is a method of producing 4-fluoroethylene carbonate, in which ethylene carbonate reacts with a mixture of fluorine and nitrogen gases. The method comprises feeding a mixture gas of fluorine gas and nitrogen gas into a reactor having ethylene carbonate charged therein, so as to react the ethylene carbonate with the mixture gas of the fluorine gas and the nitrogen gas. The mixture gas fed in the reactor is regulated to have a desired bubble size while passing through a gas bubble regulating column, in which a packing for a packed column is packed. In the method, EC directly reacts with F2/N2 mixture gas to produce FEC, thus a purification process is simple and it is possible to produce FEC at high conversion efficiency and selectivity.

Abstract: A method of producing difluoromethane (HFC-32), which includes firstly reacting methylene chloride with hydrogen fluoride in gas phase at 280 to 340° C. in the presence of a fluorination catalyst to produce chlorofluoro methane, and secondly reacting the chlorofluoro methane with hydrogen fluoride in liquid phase at 60 to 80° C. in the presence of an antimony chloride catalyst. The method is advantageous in that HFC-32 is produced in high yield under mild reaction conditions using a relatively small amount of energy.

Abstract: Disclosed is a reactor for producing a hydrofluorocarbon compound by reacting a chlorinated organic compound with hydrogen fluoride in liquid phase in the presence of an antimony chlorofluoride catalyst, comprising an inner wall B lined with a polytetrafluoroethylene (PTFE) resin, and an outer wall A. A space G of 2 to 10 mm is formed between the inner wall and the outer wall, and maintained by spiral baffles. Additionally, a plurality of vent holes with diameter of 2 to 5 mm are formed, at regular intervals of 150 to 300 mm, on the whole inner wall of the reactor. The reactor is advantageous in that the PTFE resin lined on the inner wall of the reactor is not degraded, thereby prolonging a reactor's life span and easily supplying heat to the reactor.

Abstract: Disclosed is a method of producing difluoromethane (HFC-32), which comprises firstly reacting methylene chloride with hydrogen fluoride in gas phase at 280 to 340° C. in the presence of a fluorinated catalyst to produce chlorofluoro methane, and secondly reacting the chlorofluoro methane with hydrogen fluoride in liquid phase at 60 to 80° C. in the presence of an antimony chloride catalyst. The method is advantageous in that HFC-32 is produced in high yield under mild reaction conditions using a relatively small amount of energy.

Abstract: A method of preparing lithium hexafluoro phosphate (LiPF6) using phosphorous pentachloride (PCl5), lithium chloride (LiCl), and hydrogen fluoride (HF) as raw materials. The method includes the steps of: (a) reacting the phosphorous pentafluoride with the hydrogen fluoride to prepare phosphorous pentafluoride (PF5), and (b) reacting the phosphorous pentafluoride with the lithium chloride in a hydrogen fluoride to prepare the lithium hexafluoro phosphate. Also, in this method, anhydrous hydrogen fluoride, from which moisture was removed by treating with F2 gas, is used in the steps (a) and (b), and the step (b) further comprises contacting the reaction system of the step (b) with F2 gas. Accordingly, as the method adopts relatively cheap raw materials, such as PCl5, LiCl and the like, while a highly pure F2 obtained by an electrolysis is used in the reaction system, it has an advantage in that it enables lithium hexafluoro phosphate (LiPF6) to be prepared at a high yield and purity.

Abstract: A method for producing a high purity of perfluoroethane from hydrofluoroethane (C.sub.2 F.sub.x H.sub.y 1.ltoreq.x, 1.ltoreq.y.ltoreq.5, x+y=6). Cobalt difluoride (CoF.sub.2) as a catalyst is activated into cobalt trifluoride (CoF.sub.3) as a result of the contact reaction with fluorine gas in a reactor. The reactor is purged by removing the fluorine gas remaining in the reactor. The remaining gas is allowed to react with sulfur to give sulfur hexafluoride (SF.sub.6) which is then removed. The hydrofluoroethane is converted into perfluoroethane as a result of the catalyst of the activated cobalt trifluoride at 300-350.degree. C. The feedstock is safer and less corrosive than triple bond-containing compounds such as acetylene. In the method of the present invention, the formation of CF.sub.4 is extremely restrained and no inert gases are employed, so that a very high purity of C.sub.2 F.sub.6 can be obtained at a high conversion rate.

Abstract: There is disclosed a method for the preparation of difluoromethane wherein methylene chloride is reacted with. hydrogen fluoride in liquid phase, at a temperature of about 70.degree. to 90.degree. C. under a pressure of about 11 to 12 kg/cm.sup.2.g in the presence of antimony pentachloride. It is important that the concentration of quinquevalent antimony is maintained at a level of 85% or more with the feed mole ratio of hydrogen fluoride to methylene chloride ranging from about 2.0 to 2.3.Applicable to industrial scale, the method is operated in a batch system or in a continuous system. In addition, it exhibits superior conversion rate of the materials and production yield.