Photocatalytic reforming of C3-polyols for H 2 production. Part (I). Role of their OH groups

Abstract

TiO 2 photocatalyst was prepared by sol-gel method, and then loaded with 1.0wt.% Pt by impregnation-chemical reduction method (denoted as PT). Photocatalytic reforming (PR) of C3-polyols (glycerol, propyleneglycol, and isopropanol) which have similar carbohydrate structure but possess different number of OH groups for H 2 production over PT was performed to study the role of their OH groups in the reforming reaction. The results indicated that the H 2 evolution rate and the mineralization efficiency of polyols (oxidized to CO 2) are highly correlated with the number of OH groups they contain. The more OH group it has, the higher H 2 evolution rate can be obtained, as well as the generation of CO 2. The roles of the OH group were discussed in terms of providing an anchor for the chemical adsorption of polyols to the PT and serving as an effective holes scavenger to trigger the reforming reaction. For a polyol molecule, only OH directly connected segment can be effectively converted to H 2 and CO 2 via the PR process. © 2011 Elsevier B.V.