Synergistic Effect of a Boron-Doped Carbon-Nanotube-Supported Cu Catalyst for Selective Hydrogenation of Dimethyl Oxalate to Ethanol

4 years ago

Synergistic Effect of a Boron-Doped Carbon-Nanotube-Supported Cu Catalyst for Selective Hydrogenation of Dimethyl Oxalate to Ethanol

Ronggang Fan, Yoshiharu Yoneyama, Guohui Yang, Peipei Ai, Minghui Tan, Guoguo Liu, Noriyuki Yamane, Noritatsu Tsubaki, Ruiqin Yang

Heteroatom doping is a promising approach to improve the properties of carbon materials for customized applications. Herein, a series of Cu catalysts supported on boron-doped carbon nanotubes (Cu/xB-CNTs) were prepared for the hydrogenation of dimethyl oxalate (DMO) to ethanol. The structure and chemical properties of boron-doped catalysts were characterized by XRD, TEM, N2O pulse adsorption, CO chemisorption, H2 temperature-programmed reduction, and NH3 temperature-programmed desorption, which revealed that doping boron into CNT supports improved the Cu dispersion, strengthened the interaction of Cu species with the CNT support, introduced more surface acid sites, and increased the surface area of Cu0 and especially Cu+ sites. Consequently, the catalytic activity and stability of the catalysts were greatly enhanced by boron doping. 100 % DMO conversion and 78.1 % ethanol selectivity could be achieved over the Cu/1B-CNTs catalyst, the ethanol selectivity of which was almost 1.7 times higher than that of the catalyst without boron doping. These results suggest that doping CNTs with boron is an efficient approach to improve the catalytic performance of CNT-based catalysts for hydrogenation of DMO. The boron-doped CNT-based catalyst with improved ethanol selectivity and catalytic stability will be helpful in the development of efficient Cu catalysts supported on non-silica materials for selective hydrogenation of DMO to ethanol. Better B doped: Boron doping is an efficient approach to improve the catalytic performance of carbon nanotube (CNT)-supported Cu catalysts (Cu/xB-CNTs, where x is the boric acid:CNT weight ratio in the doping process) for the hydrogenation of dimethyl oxalate (DMO) to ethanol. The Cu/1B-CNTs catalyst achieved the highest ethanol selectivity and DMO conversion, which could be attributed to high Cu dispersion, enhanced interaction of Cu species with the CNT support, appropriate distribution of Cu0 and Cu+, and suitable surface acidity.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/chem.201700821