In situ electrosynthesis of hydrogen peroxide with an improved gas diffusion cathode by rolling carbon black and PTFE

Abstract

A simply structured gas diffusion electrode (GDE) was constructed by rolling carbon black and PTFE as a conductive catalyst layer to enhance the producibility of hydrogen peroxide. A Box-Behnken design (BBD) coupled with response surface methodology was employed to assess the individual and interactive effects of the three main independent parameters (pH, current density and air flow rate) on the H 2 O 2 concentration. Analysis of variance (ANOVA) showed a high coefficient of determination value. Optimal operating conditions were a pH value of 4.0, current density of 52 mA cm À2 , and an air flow rate of 55 mL min À1 . The predicted H 2 O 2 concentration under the optimal conditions determined by the proposed model was 309.85 mM, demonstrating the improved GDE without using noble metals and other chemical promoters is a potential method for in situ electrosynthesis of H 2 O 2 . Results also revealed that the current density, air flow rate, and their interaction effect had a significant effect on the H 2 O 2 concentration, whereas changes to the initial pH had no apparent effect. Experiments showed that current density has a direct effect on the decomposition reaction in the electrolytic process.

Improved Operating Parameters for Hydrogen Peroxide‐Generating Gas Diffusion Electrodes

“…It enables the two-electron reaction step, is inexpensive and offers sufficient chemical and thermal stability [15,16]. Although carbon has been known as catalyst for nearly one century, the literature mostly focuses on the screening of novel catalysts and combinations [17][18][19][20] instead of further optimizing carbon systems through design and operation parameters [21,22]. Until today, only few studies have examined the influence of the operating parameters of H 2 O 2 -generating GDE performance according to Tab.…”

Electrical activation of hydrogen peroxide for organic contaminant degradation using an improved gas diffusion cathode

“…It is noted that there is close relationship between current density and cell potential. Higher applied current density means higher applied potential on the electrochemical system, also more tend to increase the hydrogen evolution reaction [11]. At the current density higher that 60 mA/cm 2 …”

Effect of an improved gas diffusion cathode on carbamazepine removal using the electro-Fenton process

“…4,8 The GDC is usually composed of three layers, that is, a diffusion layer, a current collector layer, and a catalyst layer. 9 Because of high specic surface area and porosity of the diffusion layer, oxygen gas can efficiently pass through the diffusion layer and reach the interface between the catalyst layer and electrolyte, resulting in low energy consumption and high production of H 2 O 2 .…”

“…8,22 Carbon black (EC-300J, Ketjenblack, Japan) of 1200 mg was mixed with each of different Na 2 SO 4 dosages to obtain mass ratios of Na 2 SO 4 to carbon black of 0%, 50%, 100%, 150%, and 200%. Each mixture was added with 30 mL of ethyl alcohol and stirred with ultrasonic treatment for 30 min.…”