Mercedes Diaz-Somoano and M. Rosa Martinez-Tarazona
Different sorbents mixed with sand are being tested for the retention of arsenic compounds in flue gases from coal combustion and gasification processes. In order to control the efficiency and the retention capacities of these sorbents and to evaluate the likely emissions into the environment, the determination of arsenic content must be carried out after the sorption. In this work, a methodology was developed for sample preparation and arsenic determination in samples with high levels of silica. The samples were kaolinite, limestone, coal fly ashes, alumina and metal oxide mixtures of iron, zinc and titanium, which were mixed with sand in the proportion 1+3, sorbent+sand. A microwave oven digestion procedure was developed for rapid dissolution of the samples, and arsenic in solution was determined by ICP-MS using standard additions. The proposed method was compared with the hydride generation AAS method and tested on a standard reference material, with reproducible and accurate results.