Cellulose Hydrogenolysis To Low Carbon Polyols Over Self-reducing Bimetallic Catalyst

Biomass, including cellulose, hemicellulose and lignin as a renewable resource formed by photosynthesis, can be expected a potential alternative material for fossil resources. Cellulose, as a main component of lignocellulosic biomass, containing D-glucose with β-1, 4-glycosidic bonds, represent a very stable property, which could be converted into fuels and chemicals. In this thesis, its controllable refinery process becomes the focus in energy chemistry field.We have focused on cellulose conversion to low carbon polyols over self-reducing catalysts. The polyols(including ethylene glycol, propylene glycol and glycerol) are the raw materials and paltform chemicals in platics and pharmaceuticals industry. The processes of celulose conversion to polyols, includes two steps(hydrolysis and hydrogenolysis),which indicates that catalysis needs cracking C-O, C-C and hydrogenating unsaturated imediates. Fortunately, the self-reducing bimetalic catalysts could achieve these challenges with promoting cellulose conversion and yields of target products. In this experiment, we screened the optimal supports firstly and then prepared self-reducing catalysts before appling into cellulose hydrogenolysis. The bio-carbon resource(sucrose), as the reducing agent, reduced the metal components during calcination process. These catalysts were characterized by BET,TG, XRD, SEM, TEM, XPS revealing that the optimal sucrose content and calcination temperature, the states and dispersion of active components. Based on target products test technology, we investigated three factors on catalytic results, including the calcination temperature,the sucrose content, the supports and metals weight ratio. The results indicated that SBA-15 and mordenite(MOR) were the optimal supports with the 3.0 g of sucrose content. The yield of low carbon polyols byusing the catalyst with the receipt of 10%Ni-15%W/SBA-15 could reach as high as 68.14%, which the ethylene glycol(EG) accounted for 61.04%.Comparatively, when MOR as the support, the yield of target products was a little lower than that of SBA-15 with 56.92% polyols.A series of self-reducing bifunctional Ni-W/SBA-15 catalysts were synthesized by using biomass-based carbon source as the reducing agent without further conventional reduction step, which was beneficial to prove economic process and experimental efficiency, providing the specific indicative value in this field. Moreover, the Ni and W catalysts with were effective to promote the selectivity of EG.