Catalytic combustion of methylenechloride

The catalytic combustion of methylenechloride, one of the chloromethanes, was investigated on metal oxide catalysts coated on the monolith support or on the spherical alumina pellets. The prepared catalysts were tested at the different temperatures between 200 and 500 degrees C and at varying GHSV values with an excess air of 216%. The catalyst having the composition of 15% Cr2O3, 5% Ce2O3 and 80%gamma-Al2O3 on the monolith was found to be ultimate due to the complete destruction of methylenechloride and to the highest mechanical stability. The operating conditions were proposed as 77778 h(-1) for the GHSV, 216% for the excess air and 400-500 degrees C for the temperature range to combust methylenechloride completely. The dependency of the reaction on methylenechloride and oxygen partial pressures was searched, and it was determined that the rate was strongly dependent on oxygen partial pressure and weakly methylenechloride partial pressure. The reaction rate expression was derived using the mechanism proposed by Downie and the reoxidation and reduction rate constants of the reaction were found as: k(i) = 4.422 x 10(-5)exp(-12597.5/RT) K-0 = 2.901 x 10(-6)exp(-4552.5/RT).