Porous Ceramics:Environmentally Friendly Materials With Very Broad Application Prospects
Porous ceramics are made of high-quality raw materials such as alumina, zirconia, and silicon carbide as main materials, and are prepared by molding and special high-temperature sintering processes. A porous ceramic material with open pores and high open porosity. , High pressure, resistance to acid, alkali and organic media corrosion, good biological inertness, controllable pore structure and high open porosity, long service life, good product regeneration performance, etc., can be applied to the precision filtration of various media and Separation, high-pressure gas exhaust muffler, gas distribution and electrolytic diaphragm, etc.
Porous ceramics are a type of ceramic material with pores as the main phase since the 1870s. Compared with glass fiber and mesh metal materials, porous ceramics have stable performance, good erosion resistance and long service life. As a honeycomb material that can exert its excellent performance in terms of separation, dispersion, absorption and fluid contact, it can be divided into two types with completely opposite operating conditions. One is for the separation of two phases; the other is for dispersing one phase into another, even if the two phases are mixed.
The main aggregate types of porous ceramics include high silica silicate materials, aluminosilicate materials, diatomaceous earth materials, stoneware materials, pure silica materials, alumina, emery materials, cordierite, aluminum titanate materials And other industrial waste, tailings, quartz glass and other materials are used in different high temperature environments, and the use temperature range is-40-1600 ℃.
The preparation of porous ceramics mainly adopts molding methods such as pressing, extrusion, dipping, casting, pouring, and hot die casting. According to different structures, porous ceramics are divided into mesh type and foam type. The mesh structure is made into high-permeability mesh ceramics after being impregnated with slurry by polymer foam plastics and subjected to high-temperature treatment. In the foam structure, pores and pore channels are formed by the high-temperature combustion of the pore-forming agent.
The main performance parameters of porous ceramics include: porosity, pore size, pore passage, pore shape, strength, and related thermal properties and chemical stability.
The shape of porous ceramics can be divided into tubular, honeycomb block, plate and film product types. Used for filter purification or catalysis of polluted water and atmosphere, sand filtration of oil well drilling, high temperature flue gas filtration and dust removal, chemical catalysis of automobile exhaust gas, molten metal filtering and slagging, etc. It is one of the basic materials to protect the environment and has a very broad application prospect.