Study On Preparation And Selective Separation Performance Of Attapulgite-based Film Materials

Inorganic membrances with superior features on resistance to high temperature, high concentration of oil content, foul ants, acid and alkali resistance, strong cleaning agent, simple preparation process and low cost, have more advantages and prospects in the industrial wasterwater treatment and recycling, especially in the oil/organic pollutants treatment. Using the resource-rich, low cost nature inorganic materials to prepare a new type of inorganic film materials, which have simple synthesis methods, comprehensive performance, are the focus of current development. In this work, we fabricated ATP-based films consisting of the rod-like ATP nano-crystals and different additives by simple suspension casting method. After modification with polydimethylsiloxane（PDMS） a low-surface-energy chemical, the surface wettability of ATP-based films was tailored from amphipathy to be superhydrophobic to water and superoleophilic to oils. A variety of analysis methods SEM, BET, XRD, tensile stress and strain, TGA were performed to measure and characteriz e the ATP-based films. And the adsorption and selective properties of oil/water separation of PAT films were studied in our experiments.1. We fabricated ATP-based films（ATP1） consisting of the rod-like ATP nano-crystals and second pulp cellulose fibers. The morpholog ical characteristics, mechanical propertis and thermal stability of the ATP 1 were investigated. Preparation of superhydrophobic and superoleophilic film PAT 1 were followed by modification with PDMS. PAT1 showed static water CA value of 163 o and water sliding angle with ca. 4.2o, suggesting an excellent surface superhydrophobicity and superoleophilicity. The results showed that the ATP1 with the ratio of 5:1 had the best tensile ability（σκ=6.14 MPa）, high thermal and mechanical flexibility. The separation efficiency of chloroform from water using PAT1 was calculated to be 91%. PAT1 also have a stable recycling performance and acid/alkali resistance, which can be used in oil/water separation.2. ATP-based films（ATP2） were prepared with a rod-like ATP nano-crystals and MnO₂ nanowires as additives and were equipped with a superhydrophobic and superoleophilic surface by modified with PDMS via chemical vapor deposition method, and named the resulting material s as PAT2. The mesoprous structure, mechanical properties and thermal stability of APT 2 and superhydrophobicity, selective separation, recyclability, acid and alkali resistance of PAT 2 were researched by SEM, BET, tensile stress and strain, TGA respectivel y. The results showed that the ATP2 with good mechanical stability, high temperature resistance, superoleophilic,recyclability and acid and alkali resistance, can be used for separating oil and organic pollutants.3. ATP-based films（ATP3） were prepared using a rod-like ATP nano-crystals and medical absorbent cotton fibles as additives, and were equipped with a superhydrophobic and superoleophilic surface by modifi ed with PDMS/toluene solution. The morphology characteristics、mechanical properties and thermal stability of APT3 were researched by SEM, XRD, tensile stress and strain, TGA et al. The results showed that the crystal structures of the purified ATP and the cotton fibles did not change after composited due to the procedures were physical preparation. PAT3 showed static water CA value of 159° and with excellent surface superhydrophobic property, recyclability and an acid and alkali resistance in certain range of p H values. PAT3 have excellent selective separation characteristic in oil/water mixture.