Effect of gamma irradiation on the adsorption and catalytic properties of rice husk-based carbons

ABSTRACT

The effects of gamma-irradiation [0.2, 0.4 and 0.8 MGy] on surface and catalytic properties of rice husk carbon activated by zinc chloride and steam have been investigated. The techniques imployed were nitrogen adsorption at -196°C and adsorption of carbon dioxide at room temperature and adsorption of sando cryl blue dye and H2O2 decomposition at 30-50°C. Also, the surface functional groups of different investigated carbon have been also determined by using neutralization with Na2CO3, NaHCO3, NaOH and NaOEt. The results revealed that the unactivated carbon measures a small specific surface area which increases upon [8-10 fold] by activation with ZnCI2 and stream. gamma-irradiation brought about a measurable significant increase in the specific surface area to an extent proportional to the dose of gamma-rays. The values of the specific surface area determined by the CO2 adsorption are much smaller than those measured by N2 adsorption this finding indicates the inaccessibility of a portion of micropore for CO2 adsorption. The investigated carbons acted as a catalyst of H2O2 decomposition and having activities much increased by activation either with ZnCI2 or steam and also by exposure to gamma-irradiation