Palladium Nanocatalysts Immobilized on Functionalized Resin for the Direct Synthesis of Hydrogen Peroxide from Hydrogen and Oxygen

Abstract

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.

Looking for the “Dream Catalyst” for Hydrogen Peroxide Production from Hydrogen and Oxygen

“…Choudhary and Samanta reported significant Pd chemical leaching from the catalyst when using phosphoric acid as promoter in concentration over 0.3 M. Chemically induced leaching was spectroscopically confirmed by observing a loss of uniform morphology of Pd nanoparticles [147]. On the other hand, physical detachment of nanoparticles from silica with no evidence of chemical leaching was confirmed by Kim et al through TEM and XRD analyses when using phosphoric acid in concentration below 0.3 M [115,169]. In order to improve retention of the Pd nanoparticle, the core@shell structure is being actively studied [172][173][174].…”

“…Park and Fierro et al [99,[111][112][113][114][115] studied the performance of Pd catalysts supported on silica functionalized with sulfonic groups and found that the SO 3 H functional groups not only can promote the generation of H 2 O 2 but also make it possible for the process to be operated using less inorganic acid, thus reducing reactor corrosion and the loss of active metal. The role of sulfonic groups was tested also in the case of sulfonated cation exchange polystyrene resins.…”

“…Catalysts prepared by anchoring Pd 2+ ions onto these organic supports were particularly effective with methanol as a solvent [114]. Lee and coworkers [115] operated the direct synthesis of hydrogen peroxide in continuous by using SO 3 H functional resin as catalyst support, and the concentration of the H 2 O 2 solution reached 9.9 wt %. The high performance of these catalytic systems results from the ability of the sulfonic acid groups of the resin to interact with and stabilize the Pd 2+ ions without further reduction to metallic palladium [116].…”

Experimental Evaluation of a Membrane Micro Channel Reactor for Liquid Phase Direct Synthesis of Hydrogen Peroxide in Continuous Flow Using Nafion® Membranes for Safe Utilization of Undiluted Reactants

“…In comparison with the literature, only Biasi et al found similarly low productivities of 180 mol H2O2 /kg Pd /h using methanol without additives as solvent in a trickle bed reactor. In continuous flow experiments, most of the groups found productivities between 1500 and 6000 mol H2O2 /kg Pd /h [41,43,44,48,52,54,55,62]; only Kanungo et al [46] stood out with achieving a productivity of 1,4300 mol H2O2 /kg Pd /h by using coated microchannel capillaries. The reactors used in the literature were mostly trickle bed reactors, stirred autoclaves or microchannel trickle beds, and hence tri-phasic systems with the related safety issues.…”

Direct Synthesis of Hydrogen Peroxide from Hydrogen and Oxygen by Using a Water‐Soluble Iridium Complex and Flavin Mononucleotide

“…[3,4] To provide an alternative, extensive efforts have been devoted to achieving the direct synthesis of H 2 O 2 from hydrogen (H 2 ) and oxygen (O 2 ) by using heterogeneous precious-metal catalysts (mainly Pd, Au, or Au-Pd). [3][4][5][6][7][8][9][10][11][12] This direct process suffers from serious problems such as unfavorable high-pressure conditions and relatively low yields owing to undesired side reactions such as formation of [3][4][5][6][7][8][9][10][11][12] For this reason, selectivity in the direct synthesis of H 2 O 2 from H 2 and O 2 has been limited. In addition, it has been quite difficult to elucidate the heterogeneous catalytic mechanism as compared with the homogeneous catalytic mechanism, in which intermediates can be detected.…”