Study On Preparation And Properties Of Mineral Porous Materials

Mineral porous materials are widely used in different fields such as environmental protection, chemical industry, pharmacy for their excellent physicochemical properties and porous structure, and much attention has been paid to the exploitation and preparation of them. In this paper, cenosphere, fly ash , coal gangue, and diatomite are used as raw materials of aggregate; bentonite, glass and sodium silicate as binder materials; charcoal powder, coal powder, common starch and soluble starch as pore forming materials, after pressure molding and conventional sintering, the mineral porous materials have been prepared. The influence of raw materials' types, formula and technical parameters on produces' properties was investigated, and the main conclusions can be drawn as follows:(1) The basic properties of the produces were determined by the aggregates' characteristic, and among the four experimented aggregates, cenosphere was the optimum one, which could make the produces being with fine adsorption capacity and stability in high temperature.(2) Binders affects molding and sintered strength of the products. When using cenosphere as aggregate, it is found that among the three experimented binders raw materials, bentonite can make the produces easy to form, and the sintering ones have a low erosion rate. So bentonite is selected as the optimum binder. (3) Pore former affects pore structure and strength of the products. Charcoal powder can make the products with the best general properties, so it is the optimum one among the four discussed pore former materials. When increasing the dosage of pore former, pore structure changed from independent pores to reticular ones .(4) Sintering temperature affects pore structure, strength and Cu²⁺ adsorption of the products. When the temperature ranges from 1000℃to 1250℃, with the ascending of the temperature, the porosity of the products increase, but the erosion rate and the Cu²⁺ adsorption amount both decrease. The porous materials prepared have preferable general properties at 1100℃.(5) Using cenosphere as aggregate, charcoal powder as pore former, bentonite as binder, by the means of mould pressing molding and conventional sintering, the products with fine properties and low cost an be prepared. The main characters of the porous materials are as follows: The porosity is 48.42%; the erosion rate is 6.58% ; the Cu²⁺ adsorption amount is 1.1mg/g.(6) Using cenosphere aggregate, the crystal phases of silicium and aluminium in the mineral porous materials prepared are variable mullite(3Al₂O₃·2SiO₂) and silimanite (Al₂O₃·SiO₂)...