Study On The Synthesis Pillared Bentonites And Their Application In Drinking-Water-Treatment

Pillared bentonites are a class of novel porous materials with high surface area,large and stable pore opening and high surface activity. These materials have numerous potential applications in many industrial fields,especially their utilization in removing pollutants from water/This article studies the synthesis of pillared bentonites .assembling and their application in table-water-treatment.A series of pillared bentonite sorbent are prepared by polyhydroxy-Al cations and polyhydroxy-Ti cations as pillaring agent,and Na- bentonite as raw material,which comes from Lin shou county,Hebei province.The reactions are studied using the batch techniques,and the relationship between the pillared amount and the concentrations of polyhydroxy-Ti ions is also investigated.Two constant,parabolic diffussion and Elovich equations are the best models to describe the pillaring reaction,while the first-order is the worst.In addition,the rate and the controlling step of pillaring reaction are studied. To some extent,the yield depends on the concentrations of polyhydroxy-metal ions.Result from XRD indicates that the pillared products are obtained.Their adsorption behaviors are studied by experiments.The results show that the modified bentonite exhibits much stronger adsorption capacity on the contaminations in aqueous solutions than untreated clays.the degradation rate may be determined by many conditions,several kinetics models can describe the reactions, and the Freundlich equation can be adaptabied to the sorption of Cr(VI) species from aqueous solution.The adsorbing mechanism and the controlling step of the reactions are investigated at the same time.A modeling porous material is also developed by using modified clays as starting material, amylogen as pore generating agent,and aluminum chloride as crosslink agent.