Investigation on supported AlCl₃ catalyst in the isomerization of E-1-chloro-3,3,3-trifluoropropene

By negative pressure sublimation, various supported AlCl₃ catalysts were prepared and further applied in the gas-phase isomerization of (E)-1‑chloro-3,3,3-trifluoropropene at higher temperatures ranging from 250 °C to 330 °C. Among these, the 2.0 wt%AlCl₃ supported on active carbon catalyst exhibited high catalytic activity within 44 h but was significantly deactivated from 44 h to 100 h. And the possible deactivation reasons of the AlCl₃ catalyst were first revealed as the following aspects: 1) The loss of AlCl₃; 2) The covering of active sites by fluorinated olefin polymerization; 3) The conversion of AlCl₃ to AlCl_xF_3-x (0 ≤ x ≤ 3) leading to the significant enhancement of strong acid sites. This work will pave the way for the subsequent development of AlCl₃ catalyst suitable for high-temperature gas-phase reaction system.