Abstract
One of the main water resources in arid Saudi Arabia is underground water. However, this brackish water has high silica content which can cause a recalcitrant deposit on the membrane in the reverse osmosis units during its desalination. In this study, we examined the synergistic efficiency of the removal of silica from the Buwaib water sample, when combining two advanced oxidation processes, γ-irradiation and the Fenton process, using hydrogen peroxide and zero valent metal iron as source of Fe3+. This latter adsorbs effectively on silica and co-precipitate. The influence of absorbed dose, iron dosage and pH effect were investigated. This preliminary study showed that these attractive and effective hybrid processes are very efficient in removing silica.
•Silica removal from water investigated with gamma radiolysis and Fenton process.•Silica removal was achieved by adsorption onto ferric hydroxide.•Silica removal depends on initial pH, equilibrium pH values and the dosage of iron.•Silica removal reached 93% when Fenton process is combined with gamma radiolysis.