A continuous process for the production of 2,2,6,6-tetramethylpiperidin-4-ol catalyzed by Cu–Cr/γ-Al2O3

A continuous process was established for the production of 2,2,6,6-tetramethylpiperidin-4-ol over Cu–Cr/γ-Al2O3 in a fixed-bed reactor. The catalyst was characterized by X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed reduction. Cu0 was believed to be the active site for the hydrogenation, and the doped chromium was supposed to exert a positive impact on the dispersion of active species. The catalyst and parameters of hydrogenation were optimized. Thus, 2,2,6,6-tetramethylpiperidin-4-ol was obtained in the yield of 90% from 2,2,6,6-tetramethylpiperidin-4-one (purity, 95%) under the optimum reaction conditions.