Research On The Removal Of Heavy Metal Ions By The Porous Ceramic Material As Asorbent

The red mud is an industrial solid offal discharged after extracting aluminium oxide from bauxite. With the development of aluminum industry, the stock of red mud is increasing year by year. Because most red mud has not been fUlly utilized, it occupied large areas of land for a long time. Then it caused the basification of the land and the pollution of the groundwater, all of these endanger the health of human being. Electroplating is one of the three major polluting industries in the world. In our country, as the rapid development of township enterprises in electroplating, the plating pollution turns more and more serious. The heavy metal ions contained in the electroplating waste water threat the survival of the animals and plantes, such as: Cr(VI),Ni2+,Cu2+,Cd2+, Hg2+ and Zn2+, etc. To solve the pollution problem of the heavy metal waste is a most urgent task about the protection of water resource now. Face to the two harmful pollutants, the research will mention innovative to use the porous ceramic materials made with red mud adsorb the heavy metal ions in the electroplating waste water, it can achieve the purpose of disposing the waste by waste.In this study, the sintered red mud-based porous ceramic material made by the Materials Science in Wuhan University of Technology will be used. The dosage of red mud accout for 60%, the burning temperature is 1120℃. After modified by the 0.01g/ml chitosan, it is used to adsorb the Cu2+ that the concentration is 15mg/L in solution. Then the removal rate can reach 80%, it is increased 35% after modification.Comparing with the removal of Cu2+ with different concentration by the sintering, joint and bayer types of red mud-based porous ceramic material, combining with their datas about porosity, water absorptivity and cold crushing strength, then it can be analysised that the removal by sintering red mud-based porous ceramic material is the best, but the cold crushing strength of it is the worst; the strength of bayer one is the best, but the removal of the copper ions is the worst.In the joint red mud-based porous ceramic material made by the Materials Science in Wuhan University of Technology, the dosage of red mud occupies 60%, the particle size is 0.8-1.25mm, the burning temperature is 1100℃. When it is used to dispose the Cu which the concentration of is 2mg/L, the removal rate is higher than 90%, and the particles have no broken after adsorption.To modify the joint red mud-based porous ceramic material with MnO2, the partical size of the sample is 1.25-1.60mm, the burning temperature is 1100℃, the temperature of heat treatment is 650℃. The result of using this sample to dispose the Pb and Cd with the concentration of 2mg/L indicates that, the removal improved obviously after modification. The removal rate of Pb can reach 100%, and the one of Cd can be higher than 90%.