Efficient Hydrogenation of Xylose and Hemicellulosic Hydrolysate to Xylitol over Ni-Re Bimetallic Nanoparticle Catalyst

Nitrogen-containing activated carbons are a new type of porous carbon materials with excellent performance in electricity storage, catalysis, and the selective adsorption, but thelow-cost preparation remains a technical obstacle for practical application. In this work, ammonia activation is developed to prepare nitrogen-containing activated carbons from abundant and sustainable biomass-basedchars by a one-step method. Highsurface-area nitrogen-containing activated carbons are produced in yields higher than 20%, with a surface area and nitrogen content greater than 2300 m2/g and 5.0%,respectively. Moreover, the four successive stages in the process of ammonia activation are suggested in terms of the evolution of the pore structure with the char burnoff；the evolution of nitrogen-containing groupsincluding pyridinic-nitrogen, pyrrolic-nitrogen, quaternary nitrogen,and −NH2 with the activation temperature are analyzed.