Phyllosilicate-Derived CuNi/SiO2 Catalysts in the Selective Hydrogenation of Adipic Acid to 1,6-Hexanediol

NiOx-promoted Cu-based catalysts derived from CuNi phyllosilicates were synthesized, characterized, and tested in the selective hydrogenation of adipic acid to 1,6-hexanediol. The reduction of the CuNi phyllosilicate allows finely dispersed Cu-0 and Cu+ on the surface. The reduced Cu36Ni5PS catalyst was found to have a higher turnover frequency for the selective hydrogenation of adipic acid than the reduced Cu41PS, Cu40Ni1PS, and Cu31Ni10PS catalysts. This catalyst is also effective at hydrogenation of succinic acid, glutaric acid, butyric acid, pentanoic acid, and hexanoic acid to their respective alcohols. The higher activity of the reduced Cu36Ni5PS catalyst is attributed to a higher oxidation state of Cu cations.