Experimental study on the thermal oxidation of 1,3-hexachlorobutadiene at 500-1100°C

Article abstract of DOI:10.1016/0045-6535(96)00038-0

Thermal degradation processes of 1,3-hexachlorobutadiene (C₄Cl₆) have been studied using a tubular flow reactor at 1 atm over the temperature range 500-1100°C for residence times of 2 seconds. Kinetic studies were performed with mixtures of 1000 ppmV of C₄Cl₆ in air. Overall Arrhenius parameters for the destruction of C₄Cl₆ were determined between 700 and 850°C. About 30 molecular halogenated products from C1 to C8 formed by pyrolysis or oxidation of 1,3-hexachlorobutadiene over the investigated temperature range were identified. Concentration profiles of major products (CO₂, Cl₂, CO, COCl₂, C₂Cl₄, CCl₄) and some minor products (C₃Cl₄O, C₄Cl₄O, C₆Cl₆, C₃Cl₄ and C₃Cl₆) have been measured as a function of temperature. Phosgene is the major chlorinated intermediate product. Detection of some aromatics such as hexachlorobenzene and octachlorostyrene show the importance of the molecular growth pathways in the chemical mechanism. Reaction pathways of main products are proposed and corresponding reaction enthalpies are estimated.