Catalytic Glycerol Oxidation Of Supported Pt Catalyst

Glycerol is one of the major byproducts from industries, especially the biodiesel industry. Since there is biodiesel production in increasing number following with a plethora of glycerol, which has inspired academic and industrial researchers to investigate the valorisation of this highly versatile molecule. Thanks to its three hydroxyl groups, it is a potential starting material for numerous value-added products, such as glycericacid, dihydroxyacetone dimer, glyceraldehyde etc. Therefore, it is of great significance that high-efficiency heterogeneous catalysts are ought to be designed to realize the utilization of glycerol in a valid way.The corresponding oxidation reactions are catalyzed by various monometallic or bimetallic catalysts supported on active carbon,graphite and multiwall carbon nanotubes. A series of bimetallic Au-Pt and monometallic Pt catalysts supported on graphene and nitrogen doped mesoporous carbon materialswere prepared, and applied to theoxidation reactions of glycerol.In this work,grephene was taken as the supports to synthesize a series of bimetallic Au-Pt via sol-gel method.The structure and morphologies of these catalysts were characterized by XRD,TEM,XPS,AES.It was found that the molar ratio of Au and Pt had a significant impact on the activity of catalysts.The selectivity of glyceric acid presents the highest when atomic ratio of Au/Pt is1:7.On the other hand,nitrogen doped mesoporous carbon materials(MCN)were prepared from ethylenediamine and tetrachloromethane by using SBA-15as hard template. Herein, a series of Pt nanoparticles supported on MCN were successfullyprepared, and characterized by N2adsorption, XRD,TEM,XPS, AES as well as CO2-TPD. The obtained catalysts exhibit uniform pore size (4-6nm), high specific surface areas, and large quantity of surface basic sites,which are helpful for the activity of catalysts. The catalysts show excellent catalytic activity when they were used for the oxidation of glycerol to glyceric acid.The highest selectivity for glyceric acid can reach up to58.5%with63.1%conversion of glycerol under the specific reaction conditions. The reaction conditions are as follows:glycerol aqueous medium0.3M, glycerol/catalyst (molecular ratio)=750:1,60℃, time for4h,base free.