Adsorption Property of the Ferrous Ion to the Washing Silica Sand Surface

The effect of washing silica sand on the adsorption property was studied using a vessel-type stirred washer. The sand sample was washed with water containing no cleaning agents. The adsorption capacity of silica sand was enhanced when it was washed at a stirring rate of more than 300rpm for 24h. The characteristics of ferrous ion adsorption to the cleaned silica sand surface were also investigated. The desorption experiments carried out with deionized water and a hydrochloric acid showed that the ferrous ions are adsorbed on the cleaned silica sand. The adsorption isotherm is a Langmuir type and the desorption of ferrous ions from the clean silica sand by washing is relatively easy because they are weakly adsorbed on the silica sand (90% of adsorbed ferrous ions are recovered by the washing).