LI Yu-shan, OUYANG Zhi-yun
(State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Science,
Chinese Academy of Science, Beijing 100085, China)

Abstract: A series of pillared interlayered clays (Al13-Bent) were synthesized by modifying bentonites with polyhydroxy aluminum (Al13). The products prepared with different amounts of aluminum added (1–4 mmol/g) were characterized by X-ray diffraction, thermogravimetric analysis, and nitrogen adsorption-desorption isotherms. The adsorption of aqueous phosphate and crystal violet onto Al13-Bent were examined. The results show that the basal spacing and the surface area of Al13-Bent increase with increasing aluminum content of Al13-Bent. The resulting Al13-Bent was shown to be more effective in adsorption of phosphate from water than the raw bentonite. The hydroxyl groups on Al13 cations and anions in the interlayer spaces of Al13-Bent are largely beneficial to the removal of phosphate. However, with increasing intercalated Al13, the removal of crystal violet by Al13-Bent decreases more in comparison with raw bentonite. The intercalation of Al13 reduces the cation exchange capacity of Al13-Bent, which is responsible for the decrease of cationic dye removal.

Keywords: Al-pillared bentonite; phosphate; crystal violet; adsorption; adsorption mechanism; wastewater treatment

Email: liyushan@ucas.ac.cn

ACTA MINERALOGICA SINICA Vol. 35, No. 2, 2015, Page 117-121