caa a22 4500 37892804X CHVBK 20180305123622.0 cr unu---uuuuu 161128e20040128xx s 000 0 eng 10.2202/1542-6580.1065 doi (NATIONALLICENCE)gruyter-10.2202/1542-6580.1065 Catalytic Pyrolysis of Difluorochloromethane to Produce Tetrafluoroethylene [Elektronische Daten] [Dae Jin Sung, Dong Ju Moon, Yong Jun Lee, Suk-In Hong] Difluorochloromethane (CHClF2, R22) has been used as a refrigerant for air conditioners and a raw material for the manufacturing of fluorinated compounds such as tetrafluoroethylene (C2F4, TFE), and hexafluoropyropylene (C3F6, HFP). TFE has been produced by the pyrolysis of chlorofluoroparaffins especially, R22, in the temperature ranges of 750 - 950 °C. To improve the relatively poor yield of TFE, the catalytic pyrolysis of R22 over activated carbon supported Cu-based catalysts was investigated. The catalytic activities over the prepared catalysts were compared with those of a non-catalytic pyrolysis reaction. Alteration of reactivity as a function of reaction time was also observed. At 650 °C and 700 °C, the yield for TFE over 10wt% Cu/A.C catalyst was higher than that in the non-catalytic pyrolysis. Reduced Cu catalysts were more active than CuO catalysts and the selectivity of HFP increased with increasing the amount of Cu loading in Cu/A.C catalysts. It was found that the reduced Cu catalyst was undergoing surface modification during the pyrolysis of R22 due to the reaction of Cu/A.C catalyst with hydrogen fluoride produced during the catalytic pyrolysis. The fresh catalysts and catalysts after the reaction were characterized by XRD and EDS. The metal fluoride formed during the pyrolysis was either CaAlF5 or Ca2AlF7, or their mixture ©2011 Walter de Gruyter GmbH & Co. KG, Berlin/Boston catalysis research nationallicence pyrolysis nationallicence difluorochloromethane nationallicence R22 nationallicence CHClF2 nationallicence tetrafluoroethylene nationallicence catalyst nationallicence Sung Dae Jin Korea University, djsung@korea.ac.kr aut Moon Dong Ju Korea Institute of Science and Technology, djmoon@kist.re.kr aut Lee Yong Jun Korea Institute of Science and Technology, yjlee_01@snogen.com aut Hong Suk-In Korea University, sihong@korea.ac.kr aut International Journal of Chemical Reactor Engineering De Gruyter 2/1(2004-01-28) 2:1 2004 2 ijcre https://doi.org/10.2202/1542-6580.1065 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.2202/1542-6580.1065 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sung Dae Jin Korea University, djsung@korea.ac.kr aut NATIONALLICENCE 700 1- Moon Dong Ju Korea Institute of Science and Technology, djmoon@kist.re.kr aut NATIONALLICENCE 700 1- Lee Yong Jun Korea Institute of Science and Technology, yjlee_01@snogen.com aut NATIONALLICENCE 700 1- Hong Suk-In Korea University, sihong@korea.ac.kr aut NATIONALLICENCE 773 0- International Journal of Chemical Reactor Engineering De Gruyter 2/1(2004-01-28) 2:1 2004 2 ijcre CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter