The promotion of Argon and water molecule on direct synthesis of H₂O₂from H₂and O₂

Abstract

Direct synthesis of hydrogen peroxide (H2O2) from H2 and O2 is an ideal route. H2/O2 plasma has a great potential for direct synthesis of high purity H2O2 without purification operations. However, low yield and high energy consumption limits the application of H2/O2 plasma in industry. This article reports that gas state Ar and H2O molecule serving as molecular catalysts promoted the synthesis of H2O2 from H2/O2/Ar/H2O plasma dramatically: the H2O2 yield was enhanced by 244% and the energy consumption was reduced by 70.9%. Ar not only increased the electron density, but also selectively accelerated the dissociation of H2 toward the formation of •HO2, a key intermediate species in H2O2 synthesis. While H2O facilitated the formation of •HO2 radical and stabilized it by forming a HO2•H2O complex, resulting in enhancing the H2O2 production. This single molecular catalysis reduced the cost of H2O2 synthesis more than 50%. © 2017 American Institute of Chemical Engineers AIChE J, 64: 981–992, 2018

Fundamental Properties and Applications of Dielectric Barrier Discharges in Plasma‐Catalytic Processes at Atmospheric Pressure

“…Optical emission spectroscopy (OES) allows to observe atomic hydrogen (H α 656.3 nm) and atomic oxygen (OI 777.4 nm and OI 844.7 nm). For the mechanism taking place a multitude of reactions has to be considered [114]:…”

“…To improve the selectivity of the process, reactions (5)-(7) have to be facilitated, while reactions (8)- (12) need to be inhibited. The Gao group [104,114] showed that the addition of Ar and H 2 O improved the efficiency by two different routes. The addition of Ar increases the electron density by lowering the required breakdown voltage.…”

“…Optical emission spectroscopy (OES) allows to observe atomic hydrogen (H α 656.3 nm) and atomic oxygen (OI 777.4 nm and OI 844.7 nm). For the mechanism taking place a multitude of reactions has to be considered : …”

Quantitative Insights into the Reaction Mechanism for the Direct Synthesis of H2O2over Transition Metals: Coverage-Dependent Microkinetic Modeling

“…Significantly, in the reaction process, the performance of H 2 O 2 production on a catalyst is largely affected by multiple relevant factors. These include H 2 and O 2 pressures, , selection of the solvents (water and alcohols), , identity of the diluent gas (N 2 , Ar, and CO 2 ), , addition of promoters (halide salts and acids), , particle effects, , and reaction temperature. In particular, it was reported that the range of H 2 /O 2 ratio was highly associated with the product selectivity during the direct synthesis process .…”

Robust Photocatalytic H2O2 Production over Inverse Opal g-C3N4 with Carbon Vacancy under Visible Light

“…With the depletion of natural resources, seeking an efficient strategy to produce H 2 O 2 is important . Nowadays, many methods have been developed, including electrochemical synthesis, alcohol oxidation, direct synthesis from H 2 and O 2 , and the anthraquinone oxidation (AO) process commercially . However, the methods mentioned above have several unavoidable disadvantages: (1) abundant energy must be consumed and the amount of organic solvents used is huge; (2) mixture of H 2 and O 2 may create potential explosion hazard; (3) organic impurities used in the AO method may contaminate the generated H 2 O 2 .…”