Study On The Synthesis Of Boehmite With Novel Morphologies And Their Application In Water Treatment

Due to novel shape, the advantages of low density, high specific surface area, high vacancy, good stability and surface permeability, Alumina hollow spheres, find their new potential applications in the areas of adsorption, catalysis, light-weight materials, ceramics and insulating materials. Anomalous alumina were made with the method of chemically induced self-transformation with template, and their adsorption performance towards selected pollutants such as Congo red, methyl blue, and phenol was evaluated. The main points of the study are as follows.1. In this work, hollow boehmite microspheres have been successfully synthesized on a large scale via a one-step hydrothermal route at 200℃. The formation of core/shell structures may involve aggregation of amorphous building clusters into spheres and their subsequent reaction, dissolution, and re-deposition process. The obtained structures are characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen adsorption/desorption measurement and UV-vis adsorption. The special surface area and pore-size distribution of the obtained product as determined by gas-sorption measurements show that the boehmite core-shell microspheres exhibit high Brunauer-Emmett-Teller (BET) surface area and porosity properties. So the obtained superstructures are promising for the applications in catalyst support, filtration, and they showed a good ability to remove an organic pollutant in waste water and are expected to be useful in many other applications.2. In this work, mesoporous alumina have been successfully synthesized via a hydrothermal route at 165℃in the presence of Triblock copolymer P123 or F127 as soft-template agents and urea as precipitating agent. their adsorption performance towards selected pollutants like as Congo red, methyl blue, and phenol was evaluated too. at the presences of F127, mesoporous alumina synthesized by aluminium nitrate shows the best adsorption.3. In this work, mesoporous alumina have been prepared at 160℃in the presence of Triblock copolymer P123 or F127 as soft-template agents and ethanol as precipitating agent after reaction 1day,2days,3days. And then their adsorption performance towards some pollutants like as Congo red, methyl blue, and phenol was evaluated too. The UV spectrophotometer used to detect the adsorption of the contamination. we can find that at the presences of aluminium muriate and after reaction 3days, mesoporous alumina shows the best adsorption.4. In our study mesoporous alumina was synthesized by hydrothermal-assisted sol-gel routes using inexpensive inorganic salts in the presence of Triblock copolymer P123 or F127 as soft-template agents. After roasting at 600℃we can receiveγ-alumina. The obtained structures are characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen adsorption/desorption measurement and UV-vis adsorption. The results shows that the specific surface area, and pore structure of the resulting y-alumina can be controlled well by introducing triblock copolymers as structure-directing agent. The BET specific surface area ofγ-alumina samples from aluminum sulfate can reach to 217.7 m2/g with pore volume reaching 0.577 cm3/g. And it shows strong adsorption of Congo red and methyl blue and ethanol. at the presences of P123. The reaction carried out only to 10 min, Congo red was almost completely removed in the experimental condition.