• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.510-515
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• 2011

The pyrolytic reaction of 1,1-dichloroethylene($CH_2CCl_2$) has been conducted to investigate thermal decomposition of chlorocarbon and product formation pathways under hydrogen reaction environment. The reactions were studied in a isothermal tubular flow reactor at 1 atm total pressure in the temperature range $650{\sim}900^{\circ}C$ with reaction times of 0.3~2.0 sec. A constant feed molar ratio $CH_2CCl_2:H_2$ of 4:96 was maintained through the whole experiments. Complete decay(99%) of the parent reagent, $CH_2CCl_2$ was observed at temperature near $825^{\circ}C$ with 1 sec. reaction time. The important decay of $CH_2CCl_2$ under hydrogen reaction environment resulted from H atom cyclic chain reaction by abstraction and addition displacement. The highest concentration (28%) of $CH_2CHCl$ as the primary product was observed at temperature $700^{\circ}C$, where up to 46% decay of $CH_2CCl_2$ was occurred. The secondary product, $C_2H_4$ as main product was detected at temperature above $775^{\circ}C$. The one less chlorinated ethylene than parent increase with temperature rise subsequently. The HCl and dechlorinated hydrocarbons such as $C_2H_4$, $C_2H_6$, $CH_4$ and $C_2H_2$ were the main products observed at above $825^{\circ}C$. The important decay of $CH_2CCl_2$ resulted from H atom cyclic chain reaction by abstraction and addition displacement. The important pyrolytic reaction pathways to describe the features of reagent decay and intermediate product distributions, based upon thermochemical and kinetic principles, were suggested.