Abstract:
PURPOSE: A method for preparing diphenyl carbonate is provided, to obtain diphenyl carbonate used as a source material of polycarbonate with a high yield in a wider temperature range within a short time with minimizing side reaction. CONSTITUTION: The method comprises the step of reacting dimethyl carbonate and phenol in a catalyst which is a mixture of an organic tin compound represented by R2SnO and a sulfuric acid derivative represented by R¬1SO3H, R is an alkyl group of C1-C6 or a phenyl group; and R1 is a halogen atom, an alkyl group of C1-C6, a haloalkyl group of C1-C6 or a tolyl group. Preferably the content of the catalyst is 0.1-10 mol% based on the amount of dimethyl carbonate; the molar ratio of the sulfuric acid derivative to the organic tin compound is 2-20; reaction temperature is 130-250 deg.C; and the reaction time is 1-24 hours.
Abstract:
The present invention relates to a catalyst for producing 1,1-difluoroethane (HCFC-152a) and producing method thereof. More particularly, it is to provide the catalyst prepared by impregnating palladium on the active carbon pretreated with an aqueous hydrogen fluoride solution and an aqueous hydrogen chloride solution in series and its use in the production of 1,1-difluoroethane (HCFC-142b) by dehydrochlorinating 1,1-difluoro-1-chloroethane at 240-300° C. in the supplying molar ratio of 2-6 (H2/HCFC-142b) with maximizing a selectivity toward the product of HCFC-152a.
Abstract:
PURPOSE: A method for preparing hexafluoropropylene and peroctafluorocyclobutane simultaneously and selectively is provided, by inhibiting the production of solid polymer and carbon and controlling the reaction temperature. CONSTITUTION: The method comprises the step of supplying tetrafluoroethylene prepared by the pyrolysis of difluorochloromethane and H2O in the molar ratio of 0.1-10 into a flow layer reactor equipped with a distributor for steam supply, to allow the dimerization of tetrafluoroethylene to be carried out. Tetrafluoroethylene is prepared at the difluorochloromethane pyrolysis device comprising a preheater(2), a super heating unit(4), a cooler and a tetrafluoroethylene distillation tower(12); is purified at the distillation tower after passing a HCl absorption tower(8), a NaOH column(9) and a dryer(10); and is supplied into the flow layer reactor from the center of the distillation tower. Preferably the reaction temperature of the dimerization of tetrafluoroethylene is 600-780 deg.C.
Abstract:
M 2 CO 3 (M=알칼리금속)의 일반식을 가지는 탄산알칼리의 촉매하에서, 1,1-디플루오로에틸렌과 메탄올을 반응시켜 1,1-디플루오로에틸메틸에테르를 제조하는 방법에 관한 것이다. 본 발명에 따른 신규의 디플루오로메틸에테르의 제조방법은 탄산알칼리 촉매를 사용함으로써, 강염기를 사용한 종래의 제조방법을 개선하여, 장치의 부식을 막고, 부산물의 생성을 감소시키고, 고수율의 산물을 얻을 수 있는 장점이 있다.
Abstract:
PURPOSE: A guidance system and a guidance method of fiber filament are provided which can lead spun fiber filament without dispersion and damage. CONSTITUTION: The guidance system is comprised of: an adapter controlling direction and speed of flow being coagulating solution; and a pump circulating and feeding the coagulating solution. The guidance method is comprised of: (a)discharging the fed coagulating solution through a nozzle or a split to a spreading funnel; (b) leading the coagulating solution and the fiber filament to a leading funnel by the discharge; and then (c)discharging the leaded coagulating solution and the leaded fiber filament through the spreading funnel at the lower speed than the (a) step.
Abstract:
본 발명은 응고도가 섭씨 30도 내지 80도 정도인 물질, 예를 들어 파라핀류등을 성형하는 성형기로서, 성형홈이 있는 성형 벨트와, 성형홈과 같은 배열의 홈을 가진 성형 롤러와, 홈을 가지지 않는 배출 롤러로 이루어지며, 성형 벨트가 2개의 성형 롤러 사이를 이동하며 연속적으로 재료를 성형 및 배출하는 성형기에 관한 것이다. 본 발명에 의해 파라핀류 등의 물질을 일정하게 성형하여 이의 사용 및 이송을 편리하게 하고, 별도의 배출 장치없이 연속적으로 성형할 수 있으며, 생산량의 조절이 용이하다.
Abstract:
본 발명은 트리클로로에틸렌과 불화수소를 원료로 사용하여 2단계 반응으로 1,1,1-트리플루오로-2-클로로에탈을 거쳐 1,1,1,2-테트라플루오로에탄을 제조하는 방법에 관한 것이다. 본 발명의 제조방법에서는 2단계 반응을 서로 다른 반응기에서 수행하며 반응기를 병렬로 배열하여 한개 반응기에서 생성된 부산물(HCl)이 다른 반응기로 투입되지 않는 것을 특징으로 한다. 1,1,1-트리플루오로-2-클로로에탄의 제조반응기에서 생성된 반응 생성 혼합물을 증류탑에서 상부 유출물과 하부 유출물로 분리할 때, 공비혼합물 형성을 이용하여 상부 유출물에서 1,1,1-트리플루오로-2-클로로에탄과 불화수소의 몰비 조성이 1 대 1 이상이 되도록 조절하여 이를 1,1,1,2-테트라플루오로에탄 제조반응에 공급되도록 한다. 본 발명에 의해 두개의 반응기에 공급되는 원료의 조성을 각각, 용이하게 조절하는 방법이 제공되며 반응에 영향을 미칠 수 있는 미반응 물질 및 부산물이 다른 반응기에 투입되지 않도록 할 수 있다.
Abstract:
The catalyst for manufacturing chlorine is made by; (a) mixing the aqueous solution of CrO3 of 6 anions with ethanol; (b) heating and refluxing at above 90 deg.C; (c) calcinating at 400-500 deg.C for 3-10 hrs after seperating and drying the precipitate;(d) molding with 3-10 wt% stearic acid dissolved in chloroform added. Chlorine is prepared by reacting HCl and oxygen at the molar ratio of 4:1-4:4 at 350-375 deg.C under the catalyst Cr2O3.