| Geopolymer is a kind of green gelatinization materials which is obtained at low temperatures by using solid powder containing such raw materials like active silicon aluminum and alkali activator etc. after the appropriate process. It has many advantages such as high temperature resistance, durability, acid and alkali resistance, and fast speed of gelation and hardening and so on. Because of its excellent properties, geopolymer has caused wide attention and research of scholars both at home and abroad in recent years.At present, the research on geopolymer in the field of inorganic membrane application development and other aspects is still blank around the world, this research will solve the problems during the traditional inorganic membrane’s preparation processes, such as high total cost, complex processes, high energy consumption, environmental pollution and other issues, which is one of the important directions of geopolymer materials development. Not only does it have high academic values, but also it has good market development prospects and huge economic benefits.Based on our preliminary research, this study obtained self-supporting metakaolin based geopolymer inorganic membranes by using injection molding, did research on compressive strength, microstructure, specific surface area and pore size distribution of geopolymer inorganic membrane meterials through many test means such as universal pressure tester, scanning electron microscopy, specific surface area and porosity test instrument, and automatic aperture analyzer and so on. This paper analyzed the modulus of water glass（SiO2/Na2O molar ratio）, sodium and water ratio（H2O/Na2O molar ratio）, the influence of curing temperature, curing time, vacuum defoaming on inorganic membrane meterials’structure parameters, and then it analyzes the mechanism from the micro level, it was found that we can achieve the controlling goals of geopolymer inorganic membrane preparation technology by adjusting these factors. And its separation performance was tested, the main conclusions are as follows:（1） Fix Na2O/Al2O3（molar ratio） is 0.8, inorganic geopolymer membranes have higher compressive strength and high specific surface area under the below formula:modulus sodium silicate is 1.3 mold, water and sodium ratio is 19.（2） Within the 40-60 ℃ temperature range, the rise of temperature plays a positive role in the inorganic membrane’s early strength enhancement. When the reaction temperature is too high, it will result in a decline in strength; The extension of curing time is beneficial to the improvement of the samples’ compressive strength, the compressive strength of geopolymers promotes obviously during the 24 hours in the initial reaction period, and the promotion weakens in the later period.（3） Vacuum defoaming treatment can effectively improve strength of inorganic membranes than without defoaming treatment. Moreover, it’s conducive to get inorganic membranes with narrow pore size distributions.（4） Prepare geopolymer slurry according to the formula:Na2O/Al2O3molar ratio) is 0.8, SiO2/Na2O（mo lar ratio） is 1.3, H2O/Na2O（molar ratio） is 19, carry out vacuum defoaming treatment for geopolymer slurry, and then dismantle the moulds to obtain geopolymer inorganic membranes after curing them for 24 hours when the temperature is 60 ℃. The compressive strength and specific surface area of the above inorganic membrane materials respectively are 29.03 MPa and 20.51 m2·g-1, porosity is 39.18%.（5） The separation performance test of inorganic membranes shows that: under the certain filtration pressure, water flux of membranes and membrane thickness are negatively correlated. Under the certain membrane thickness, water flux of membranes and filtration pressure are positively correlated; The interception rate of the inorganic membranes are 100%for the nano Al2O3 with average particle size of 50-100 nm.The change of membrane thickness doesn’t affect the interception rate, so does the change of filtration pressure. |
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