Carbon spheres derived from biomass residue via ultrasonic spray pyrolysis for supercapacitors

A disadvantage of the commercial Raney Ni is that the Ni active sites are prone to leachingand deactivation in the hydrogenation of xylose to xylitol. To explore a more stable and robust catalyst,activated carbon (AC) supported Ni-Re bimetallic catalysts (Ni-Re/AC) were synthesized and usedto hydrogenate xylose and hemicellulosic hydrolysate into xylitol under mild reaction conditions.In contrast to the monometallic Ni/AC catalyst, bimetallic Ni-Re/AC exhibited better catalyticperformances in the hydrogenation of xylose to xylitol. A high xylitol yield up to 98% was achieved over Ni-Re/AC (nNi:nRe = 1:1) at 140 C for 1 h. In addition, these bimetallic catalysts also had superior hydrogenation performance in the conversion of the hydrolysate derived from the hydrolysis reactionof the hemicellulose of Camellia oleifera shell. The characterization results showed that the addition ofRe led to the formation of Ni-Re alloy and improved the dispersion of Ni active sites.