Zn-doped nano-Cr2O3 catalyst for fluorination of chlorinated light olefins

•Zn-doped Cr-based catalysts were prepared for fluorination of chlorinated olefins using anhydrous hydrogen fluoride.•Appropriate Zn doping can increase the content of Cr (VI) in the catalyst increasing the number of active species.•The SCS-Cr / Zn-40 exhibits excellent catalytic activity for the industrial manufacture of high-purity VDF. A series of Zn-doped nano-Cr2O3 catalysts were prepared by the microwave-assisted combustion method, and the catalysts were successfully applied to the fluorination of 1, 1, 2, 3-tetrachloropropene to synthesize 2-chloro-3, 3, 3-trifluoropropene, and the fluorination of vinylidene chloride to vinylidene fluoride using anhydrous hydrogen fluoride, which is much more efficient than catalyst reported in literatures. By XRD, XPS, and NH3-TPD, it was confirmed that the doping of a small amount of Zn did not have a great influence on the crystal structure of the catalyst but had a great influence on the acidity of the catalyst surface, which increased the number of weak acids and medium acids on the catalyst surface. In addition, the addition of a small amount of Zn could increase the content of high-valent chromium and produce more CrOxFy active centers. As the number of acid sites increases, it provides adsorption centers for chlorine-containing molecules, and the increase of CrOxFy active centers promotes the reaction. They work together to improve the catalytic performance of the catalyst. [Display omitted]