The waste H2SO4 reagents generated in semiconductor industries during manufacturing processes usually contain high concentration of hydrogen peroxide.  In order to reuse the acid regents it is necessary to remove the hydrogen peroxide. The removal of hydrogen peroxide from sulfuric acid solution was studied using carbon-based materials. It is hypothesized that the presence of oxygen functional groups on the carbon-based materials will be electron donors that enable the reduction of hydrogen peroxide under acidic condition. It is further hypothesized that the ash components of carbon based materials exert catalytic effect that expedites hydrogen peroxide reduction reactions.  First, the carbon based materials including commercial activated carbon, namely, Filtrasorb 400 and Nuchar SA, and different biochars were characterized for surface properties, specifically, surface charge and surface redox species. Potentiometric titration of carbon based materials by strong oxidants such as Ce4+ revealed the presence of a series of specific redox pairs on the carbon surface. Anodic oxidation over DSA electrode and FTIR analysis further revealed the presence of redox species on the carbon based materials.  Zeta potential measurements yielded pH-dependent surface charge and pHzpc, which controlled the surface reactions.  Preliminary results showed that hydrogen peroxide oxidation was dependent on the type and the quantity of carbon surfaces. Carbon based materials of high pHzpc were more effective in hydrogen peroxide reduction than those of low pHzpc. The ash content of carbon based materials also played a crucial role in catalyzing hydrogen peroxide reduction. Results also showed that sulfate was relatively inert toward the carbon based materials, which enabled the separation and recovery of sulfuric acid molecules from the hydrogen peroxide mixture.

Reduction of hydrogen peroxide over biochar surface in acidic solution

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.