Removal Of Fluoride, Phosphate And Organic Anionic Dye Using Alkaline White Mud

With the development of economy and increase of population, discharge of wastewaters from municipalities, industries is increasing a series of question, among which fluoride, phosphate and anionic dye are the commonly pollutants. Fluoride pollution has done harm on many millions of people in many parts of China. Phosphate is one of key factor for eutrophication of water bodies. Therefore, reduction of phosphate from wastewaters before discharge is critical for preventing eutrophication of waters and occurrence of alga bloom. The anionic dye is visible even at very low concentrations and destructs aquatic ecosystems due to interfering with penetration of sunlight into waters. Defluoridation, removal phosphate, removal dye of wastewaters is now an important topic in the environmental community.In recent years, several methods were tried for removal of inorganic and organic pollutants from water, namely, adsorption, ion exchange, electrochemical flocculation, and chemical precipitation. Among these, adsorption is feasible for removal of lower concentration of anionic pollutants, while chemical precipitation is fit to higher concentration.. Many inorganic and organic pollutants can be removed by precipitation using soluble calcium. However, the addition of calcium-bearing chemical reagent will increase the cost of treatment. Alternatively, materials containing Ca(OH)₂, CaSO₄, CaCO₃ are often used in disposal of wastewater treatment for economic consideration.Alkaline white mud (AWM) is of fine particle with large surface area and high adsorption capacity. Soluble calcium in AWM may cause precipitation of anionic pollutants including fluoride, phosphate and anionic dyes. In the present study, we utilize AWM to remove fluoride, phosphate and an anionic dye from simulated wastewater. The main contents of our experiments included: the effects of contact time, temperature, initial pH, initial adsorbate concentration, adsorbent dosage,...