Synthesis, Characterization And Performance Of As Removal Of The Iron Coated Pottery Granules

This paper introduced the iron coated pottery granules adsorbent materials prepared by the method of solution impregnation-activation with iron salt and kaolin as raw materials. The effect of soaking time, the content of iron salt, sintering temperature and the content of pore-forming agent on physical attributes and As removal performance of the iron coated pottery granules adsorbent materials were determined by SEM, BET, IR and XRD and static adsorption isotherm experiments. The best preparation conditions were determined by orthogonal design, and characterizated and tested the performance of the As removal of the materials under the best preparation conditions.Results show that sintering temperature, the content of iron salt and the content of pore-forming agent have significant impact on the physical attributes and As removal performance of the adsorbent materials. The order is sintering temperature> the content of iron salt> the content of pore-forming agent, and the best preparation conditions are when the sintering temperature is 1300℃, the content of iron salt is 1.125mmol/g, the content of pore-forming agent is 5%.The results of SEM, BET, IR and XRD analysis show that, the surface of the material filled with various sizes of pores, these provide a broad surface area for adsorption of arsenic. There is a certain amount of Fe-OH as active sites for absorption of arsenic. It is another important reason for the material can be an effective adsorbent to arsenic removal. The elemental iron of adsorbent materials is mainly in the form of goethite and hematite. The sintered kaolin became to a stable structure—Mullite for the goethite and hematite provides a good carrier with chemical stability and high strength.The adsorbent materials with good mechanical strength are stable in aqueous solution, almost no iron overflow. The size of the materials is 1-2mm, it is easy to separate from the water. Meanwhile, the results of static adsorption isotherm experiments showed that the adsorbent materials have good performance of As removal as the trivalent arsenic removal rate reach 74.7% and the mixed arsenic removal rate reach 81.5%. If reasonable study this materials, there will be a good practical value.