Some strategies to provide the global energy demand have been the increasing of production levels or the use of renewable energy for that purpose. These have shown economic, environmental and technical advantages, among others against fossil fuels, due to reducing of greenhouse effect (principally CO2). In this sense, the hydrogen production has been converted in a good option due to its high calorific power and clean combustion. The principal ways to hydrogen production are reforming or partial oxidation of hydrocarbons (methane) and alcohols, water electrolytic dissociation, and photochemical process, etc. A special technique has been the conversion of solar to chemical energy through a semiconductor (photocatalysis). This has shown promissory results, but the performance levels reached by the photocatalytic and photoelectric process through the water dissociation, even are not feasible because of the low activity of the semiconductors (absorption light range), electron-hole pairs recombination and reverse reaction. To improve the semiconductor response, several strategies has been used for example, doping with noble metals, synthesis of new structures and the use of sacrificial agents to improve the electron transfer however, in some cases, these options are limited by the technical requirements and implementation costs. Recently, there is an interest in catalytic process on mineral surfaces or geocatalysis (a chemical phenomenon that occurs in many natural process). Due to presence of many metals on natural aggregates, have been used minerals such as ilmenite and sphalerite to degrade organic and chlorinated compounds. In this research, the photocatalytic activity of black sand mineral was tested through response surface methodology (22 factorial + central points) to evaluate the effect of independent variables such as pH, sacrificial agent concentration, catalyst dose and the electron donor agent type, for hydrogen production. Variables such as agitation speed and radiation intensity were hold constant by the time. The results obtained showed a simultaneous hydrogen production and degradation of sacrificial agent, and the better conditions observed were at acid conditions and higher levels sacrificial agent. The results shown the potential use of mineral semiconductors and it could be used in several photocatalytic process.

Photocatalytic hydrogen assessment for production using black sand as semiconductor: The application in photocatalysis process

253rd National Meeting (2017)

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