Mechanism of Catalytic Additive Chlorination of Ethylene to 1,2-Dichloroethane

A mechanism for the direct additive chlorination of ethylene to 1,2-dichloroethane in the presence of FeCl3 catalyst promoted by NaCl was proposed and verified. It was found that the reaction rate depends on the concentration of the active phase of the catalyst and the promoter and is also determined by their interaction with the formation of NaFeCl4. It was shown that the surface intermediate of the reaction is the Na[Fe(C2H4Cl)4] complex. A heterogeneous–homogeneous mechanism, according to which the reaction begins on the surface of the catalyst and continues in the 1,2-dichloroethane solution, was established for the process.