Direct synthesis of hydrogen peroxide from hydrogen and oxygen over palladium catalyst supported on SO3H-functionalized mesoporous silica

Palladium catalysts supported on SO3H-functionalized mesoporous silicas (denoted as Pd/SO3H-MCM-41, Pd/SO3H-MCM-48, Pd/SO3H-MSU-1, Pd/SO3H-SBA-15, and Pd/SO3H-MCF) were applied to the direct synthesis of hydrogen peroxide from hydrogen and oxygen. For comparison, palladium catalysts supported on mesoporous silicas (denoted as Pd/MCM-41, Pd/MCM-48, Pd/MSU-1, Pd/SBA-15, and Pd/MCF) were also employed for the direct synthesis of hydrogen peroxide. Selectivity for hydrogen peroxide, yield for hydrogen peroxide, and final concentration of hydrogen peroxide over Pd/SO3H-functionalized mesoporous silica catalysts were much higher than those over Pd/mesoporous silica catalysts. Yield for hydrogen peroxide increased with increasing acid density of Pd/SO3H-functionalized mesoporous silica. Pd/SO3H-functionalized mesoporous silicas efficiently served as an alternate acid source and as an active metal catalyst in the direct synthesis of hydrogen peroxide from hydrogen and oxygen. (C) 2009 Elsevier B.V. All rights reserved.