Abstract: The role of cerium in the copper-based catalyst in HCl oxychlorination was t o transfer oxygen during the reaction, which accelerated the rate-determining s tep. In the used catalyst reacted for 300 h, the main part of cerium reacted wit h the carrier to form an inert phase, which had no co-catalytic effect.

Key words: oxychlorination, cerium, copper-based catalyst, oxygen storage, deactivation