The pyrolysis of 1,2-dichloroethane (EDC) is investigated by a novel apparatus which incorporates a microcracking furnace into a gas chromatograph equipped with a capillary separation column. The device allows for the vaporization and pyrolysis of the liquid feed, in addition to sampling and analysis of the furnace effluent, to be accomplished in a single experimental run. This design circumvents the problems normally encountered when sampling a two-phase mixture containing toxic and corrosive materials. Moreover, it provides the most complete analysis of 1,2-dichloroethane pyrolysis reported to date. Results demonstrating the influence of conversion parameters such as pyrolysis temperature and residence time on product distribution are presented. It is also shown that kinetic parameters for such pyrolysis reactions can be measured with the GC pyrolysis apparatus. The simple and versatile apparatus could also be used to quantitatively study the pyrolysis of other liquid feedstocks such as naphthas, condensates, and other chlorinated hydrocarbons.