Preparation And Properties Of Electrolytic Manganese Residue Porous Ceramic Materials

With the rapid development of electrolytic manganese industry, the amounts of discharge of electrolytic manganese residue has become very large. A large amount of electrolytic manganese residue not only occupys a large amount of land, but also seriously threatens the environment. The heavy metal pollution problem caused in the process of electrolytic manganese production also becomes increasingly worse. Therefore, the utilization of electrolytic manganese residue and the treatment of the heavy metal pollution problem have become a hot issue as well as a critical problem to the industry of electrolysis manganese and the field of environmental protection. This paper uses electrolytic manganese residue as the main raw material and pore-forming agent to prepare the porous ceramic materials with high added value and high performance, they can be used to adsorb and remove the heavy metals in the waste water. This thesis explored the new way to meet the need of comprehensive utilization of electrolytic manganese residue.The paper has researched the effects of the sintering temperature, the shaping pressure, the category and the content of pore-forming agent and the particle size distribution of carbon powder on properties of porous ceramic materials, investigated the process of the forming pore of porous ceramic materials with different pore-forming agents. The paper also investigated the bonding effeets of the bentonite and kaolin. Through the experiment, appropriate pore-forming agent and binder are chosen. charcoal powder as pore-forming agent and kaolin as binder can prepare the porous ceramic materials with the best general properties, and the porous ceramic material has high compression strength with dolomite as pore-forming.The influences of the particle size distribution of electrolytic manganese residue, the sintering temperature, the holding time and the shaping pressure on the porous ceramic material of porosity, water absorption, volume density and compression strength were investigated. Through a series of experiments, it has been known that when the optimizing conditions to prepare oxidation manganese residue porous ceramic material with single pore-forming agent in a experiment are:the content of carbon powder is20%, kaolin addition is5%, the sintering temperature is1075℃, the holding time is60minutes, the shaping pressure is4MPa. The results showed that with the best technological condition, porosity was68.86%, water absorption was66.19%, density was1.05g/cm3and compressive strength was5.44MPa. Meanwhile, when the optimizing conditions to prepare carbonate manganese residue porous ceramic material with single pore-forming agent in a experiment are:the content of carbon powder is20%, kaolin addition is10%, the sintering temperature is1100℃, the holding time is60minutes, the shaping pressure is3MPa. The results showed that with the best technological condition, porosity was63.85%, water absorption was62.43%, density was1.06g/cm3and compressive strength was4.69MPa.Through orthogonal tests optimize suitable formula and process to control the porosity and the compression strength of the oxidation manganese residue porous ceramic material with composite pore-forming agent, it is found that the content of pore-forming agents and the sintering temperature have the strongest effects on the porosity of the porous ceramics of composite pore-forming agents, followed by the content of kaoline as binder, and next followed by the shaping pressure. The optimum technological parameter is:the kaolinic content is5%, the content of the carbon powder is20%, the dolomite content is7.5%, the shaping pressure is3MPa, the sintering temperature is1100℃, the holding time is60minutes. Under these experimental conditions, oxidation manganese residue porous ceramic materials with composite pore-forming agents can be prepared with a porosity of69.79%, a volume density of0.97g/cm3and water absorption of69.38%and compressive strength was6.98MPa.The XRD examination shows that the main mineral constituents of electrolytic manganese residue porous ceramic materials are anorthite, quartz and the iron acid manganese of spinel ferrite manganese, which increase the strength of the materials; after being implanted into the ferrite lattice and the manganese sulfide lattice, the chemical element of manganese will become a part of the crystalloid, realizing the innocent treatment of the manganese residue. The analysis of SEM micrographs of fracture surfaces of the electrolytic manganese residue porous ceramic materials shows that the pores of the manufactured electrolytic manganese residue porous ceramic materials are plentiful and they are distributed evenly, with small bore diameters, the bore structures being3-dimemsional and connected.This paper has investigated the removal effects of heavy metal waste water containing copper, manganese, zinc, lead and chrome by porous ceramics with different physical and chemical properties on the sorption process. The results showed that the removal effects of heavy metal waste water by porous ceramics are very good.