Process and apparatus for preparing 1,2-Dichloroethane by direct chlorination If in the reaction of ethylene with chlorine to form 1,2-dichloroethane (EDC) the catalyst components sodium chloride and iron(III) chloride are used in a molar ratio of below 0.5, then the EDC is obtained in sufficiently high purity to allow direct conversion to vinyl chloride. With maintenance of the stated molar ratio the reaction can be carried out very advantageously in terms of equipment and energy consumption, for example by vaporizing some of the EDC in an expansion vessel.