Solid acid additives as recoverable promoters for the direct synthesis of hydrogen peroxide

The effectiveness of Cs-exchanged phosphotungstic acid as a recoverable solid acid additive for the direct synthesis of hydrogen peroxide (H2O2) using an Au-Pd / TiO2 catalyst is investigated and compared to the promotion effect of common oxides and non-halo acids. A clear improvement in catalytic activity towards H2O2 synthesis is reported when utilising Cs-containing heteropolyacids in addition to a standard H2O2 synthesising catalyst. The effect of Cs content on the promotion of H2O2 formation is investigated and the feasibility of a reusable heterogeneous additive has been explored revealing that the presence of the acid additive not only stabilises the H2O2 that is produced but also increases the H2O2 synthesis rate