The direct synthesis of hydrogen peroxide (DSHP) from H2 and O2 is conceptually the most ideal and straightforward reaction for producing H2O2 in industry. However, precisely tailored catalysts are still in progress for large scale production. Here, we report highly efficient and industrially relevant catalysts for the direct synthesis of H2O2 from H2 and O2 prepared by the immobilization of Pd nanocatalysts onto a functionalized resin. The continuous production of 8.9 wt % H2O2 and high productivity (180 g of H2O2 (g of Pd)−1 h–1) is achieved under intrinsically safe and less-corrosive conditions without any loss of activity. We expect this approach is a substantial improvement of nanocatalysts for direct synthesis of hydrogen peroxide from hydrogen and oxygen and will greatly accelerate the industrially relevant process of on site production of hydrogen peroxide soon.

No abstract

No abstract

ZnMe III FeO 4 catalysts with different trivalent metal (Me III = Fe, Al, Cr, Mn, and Co) were prepared by a co-precipitation method, and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene. Successful formation of ZnMe III FeO 4 catalysts was confirmed by XRD and ICP-AES analyses. Catalytic performance of ZnMe III FeO 4 catalysts in the oxidative dehydrogenation of n-butene strongly depended on the identity of trivalent metal (Me III ). Acid properties of ZnMe III FeO 4 catalysts were measured by NH 3 -TPD experiments, with an aim of correlating the catalytic performance with the surface acid property of the catalysts. It was revealed that yield for 1,3-butadiene increased with increasing surface weak-acid density of ZnMe III FeO 4 catalyst. Among the catalysts tested, ZnFeFeO 4 catalyst with the largest surface weak-acid density showed the best catalytic performance in the oxidative dehydrogenation of n-butene.

No abstract

Pure bismuth molybdate (c-Bi 2 MoO 6 ) and multicomponent bismuth molybdate (Co 9 Fe 3 Bi 1 Mo 12 O 51 ) catalysts were prepared by a co-precipitation method, and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene. The Co 9 Fe 3 Bi 1 Mo 12 O 51 catalyst showed a better catalytic performance than the c-Bi 2 MoO 6 catalyst in terms of conversion of n-butene and yield for 1,3-butadiene, indicating that the multicomponent bismuth molybdate was more efficient than the pure bismuth molybdate in the oxidative dehydrogenation of n-butene. It was revealed that the crucial factor determining the catalytic performance of Bi-Mo-based catalyst in the oxidative dehydrogenation of n-butene is not the amount of oxygen in the catalyst involved in the reaction (oxygen capacity) but the intrinsic mobility of oxygen in the catalyst involved in the reaction (oxygen mobility). The enhanced catalytic performance of Co 9 Fe 3 Bi 1 Mo 12 O 51 was due to its facile oxygen mobility.

A series of metal ferrite (Me II Fe 2 O 4 ) catalysts were prepared by a co-precipitation method with a variation of divalent metal component (Me II = Zn, Mg, Mn, Ni, Co, and Cu) for use in the oxidative dehydrogenation of n-butene to 1,3-butadiene. Successful formation of metal ferrite catalysts with a random spinel structure was confirmed by XRD, ICP-AES, and XPS analyses. The catalytic performance of metal ferrite catalysts in the oxidative dehydrogenation of n-butene strongly depended on the identity of divalent metal component. Acid properties of metal ferrite catalysts were measured by NH 3 -TPD experiments, with an aim of correlating the catalytic performance with the acid property of the catalysts. It was revealed that the yield for 1,3-butadiene increased with increasing surface acidity of the catalyst. Among the catalysts tested, ZnFe 2 O 4 catalyst with the largest surface acidity showed the best catalytic performance in the oxidative dehydrogenation of n-butene.

Palladium-containing insoluble heteropolyacid (HPA) catalysts (Pd 0.15 M 2.5 H 0.2 PW 12 O 40 ) were prepared by an ion-exchange method using various alkaline metal ions (M = K ? , Rb ? , and Cs ? ) (denoted as Pd-KPW, Pd-RbPW, and Pd-CsPW). They were then applied to the direct synthesis of hydrogen peroxide from hydrogen and oxygen. Conversion of hydrogen over the catalysts was almost identical with no great difference, while selectivity for hydrogen peroxide increased in the order of Pd-KPW \ Pd-RbPW \ Pd-CsPW. As a consequence, yield for hydrogen peroxide increased in the order of Pd-KPW \ Pd-RbPW \ Pd-CsPW. It was found that yield for hydrogen peroxide increased with increasing Pd 3d 5/2 binding energy of the catalyst. Among the catalysts tested, Pd-CsPW catalyst with the highest Pd 3d 5/2 binding energy showed the highest yield for hydrogen peroxide.