Study On Adsorption Of Bentonite And Pillared Bentonite To Heavy Metals And Organic Compounds From Aqueous Solution

Bentonite and pillared bentonite were novel porous materials with large surface area and high surface activity ,which exhibited strong capacity of removing the micro-pollutants from in aqueous solution. This article studied the synthesis of pillared bentonites ,shaping, and the adsorption of trace heavy metals and organic compounds in water.Ti-pillared bentonite was prepared using the bentonite from Linshou country in Hebei province as raw material and polyhydroxy-Ti cations as pillaring agent. In the light of the wetting swelling capacity of powder bentonite and its difficult separation from water in pratical application, the molding experiment of bentonite and Ti-pillared bentonite have been carried out and defined The feasible condition.In the light of the adsorption of trace chloroform ,chromium(VI) and chloroacetic acid in water, study on removal of trace chloroform ,chromium(VI) and chloroacetic acid from aqueous solution at 25℃ have been carried out using Ti-pillared bentonite, formed bentonit and formed Ti-pillared bentonite prepared as sorbent respectively. The effect of adsorbate concentration, contact time and adsorbate addation on the adsorption process were discussed. The adsorption capability of different absorbate was compared.Furthermore,the adsorption isotherm of chloroform ,chromium(VI) and Chloroacetic acid on bentonite are also determined respectivly. The adsorption mechanism of chloroform,chromium(VI) and Chloroacetic acid on the bentonite are studied respectivly.The properties of Bentonite,Ti-pillared bentonite, formed bentonit and formed Ti-pillared bentonite were determined by XRD and specific surface area measurements.According to the XRD and specific area analysis ,the results show that the specific area of molding bentonite and molding Ti-pillared bentonite is reduced. The molding bentonite crystal layer collapses and its heat stability becoming feebleness,but molding Ti-pillared bentonite has better heat stability because of TiO₂ locking the layer and preventing crystal layer collapse.