Promoting Effect of Ni on the Catalytic Production of Alanine from Lactic Acid over RuNi/AC Catalyst

A series of RuNi bimetallic catalysts supported on activated carbon were prepared to study the reductive amination of lactic acid. Among the tested catalysts, the catalyst containing 40% Ni and 60% Ru was selected as the optimal catalyst. The yield of alanine significantly increased to 64% using the Ru6Ni4 catalyst supported on an activated carbon, which was 1.5 times that using the monometallic Ru catalyst supported on an activated carbon. A number of characterization methods such as transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and temperature-programmed reduction (TPR) were used to characterize monometallic and bimetallic catalysts. The strong electron transfer between Ni and Ru and the highly dispersed structure of metal on the surface of the support contributed to the excellent catalytic performance of Ru6Ni4. The Ru6Ni4 catalyst supported on activated carbon also exhibited good activity in the reductive amination of other α-hydroxyl acids to corresponding amino acids.