Fast Adsorption of Chromium (VI) Ion from Synthetic Sewage Using Bentonite/ Bio-coal Composite

The pollution of environment caused by toxic heavy metals is one of the most important andchallenging issues of the day. Their presence in fresh surface and ground water is becoming asevere threat to the environment and public health. According to the figures reported by theWorld Health Organization (WHO), an average of 50,000 people die each day from diseasesassociated with contaminated water i.e. one person in every two seconds. Chromium (Cr) is aheavy 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 thetrivalent form however, excessive amounts of Cr (VI) cause DNA damage, which can causecancer, birth defects, respiratory problems, and many other health problem [2]. Therefore,considering the hazards of these heavy metals, they must be removed from wastewaters beforeentering to the environment and water bodies.The removal of heavy metals ions from aqueous solutions and wastewaters is performedthrough different physical and chemical methods including chemical deposition, ion changing,electronicmethods, membrane filtrations, reverse osmosis, solvent extraction, and adsorption [3].In this study, the main objective was to produce clay/activated carbon composite as asorbent to remove chromium (VI) ion from aqueous solutions. FT-IR, SEM, and XRD analyzeswere used to verify the properties of clay/activated carbon composite. The effect of pH on theadsorption efficiency of chromium ion (VI) from aqueous solution was studied and themaximum efficiency was determined at pH 3.

Keywords:

Bentonite , Composite , Aqueous Solution , Activated Carbon