مشخصات پژوهش

The pollution of environment caused by toxic heavy metals is one of the most important and challenging issues of the day. Their presence in fresh surface and ground water is becoming a severe threat to the environment and public health. According to the figures reported by the World Health Organization (WHO), an average of 50,000 people die each day from diseases associated with contaminated water i.e. one person in every two seconds. Chromium (Cr) is a heavy metal that occurs in several oxidation states, but only two prevail in the geoenvironment, trivalent (Cr3+) and hexavalent (Cr6+). The body can naturally reduce hexavalent chromium to the trivalent form however, excessive amounts of Cr (VI) cause DNA damage, which can cause cancer, birth defects, respiratory problems, and many other health problem [2]. Therefore, considering the hazards of these heavy metals, they must be removed from wastewaters before entering to the environment and water bodies. The removal of heavy metals ions from aqueous solutions and wastewaters is performed through different physical and chemical methods including chemical deposition, ion changing, electronic methods, membrane filtrations, reverse osmosis, solvent extraction, and adsorption[3]. In this study, the main objective was to produce clay/activated carbon composite as a sorbent to remove chromium (VI) ion from aqueous solutions. FT-IR, SEM, and XRD analyzes were used to verify the properties of clay/activated carbon composite. The effect of pH on the adsorption efficiency of chromium ion (VI) from aqueous solution was studied and the maximum efficiency was determined at pH 3.