سال انتشار: ۱۳۸۷

محل انتشار: دومین کنگره بین المللی علوم و فناوری نانو

تعداد صفحات: ۲

نویسنده(ها):

M Khatamian – Department of Inorganic Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
A Olad – Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz,Tabriz, Iran
B Naseri –
Z Ramazani –

چکیده:

Chromium is a redox active metal that exists as either Cr(III) or Cr(VI) in the environment. The Compounds of Cr(III) are reported as being 10–۱۰۰ times less toxic than those of Cr(VI) Thus, the reduction of Cr(VI) to Cr(III) reduce its toxicity [1]. The traditional treatment is reduction of Cr(VI) to Cr(III) followed by precipitation. The Cr(III) is precipitated as hydroxide at alkaline conditions using either caustic soda or lime [2]. The major shortcoming of the conventional treatments involves a lengthy process, significant sludge production, and chemical costs and low efficiency. Development of new technologies to improve or substitute the above conventional process is economically and environmentally desirable. Natural zeolites, due to their large surface areas, high cation exchange capacities, and low cost, are a major class of materials being considered for adsorption of different species. Zeolites possess a net negative structural [3]. This permanent negative charge results in the favorable ion exchange selectivity of zeolites for certain cations, and makes natural zeolites of interest for use in the treatment, municipal and industrial wastewaters. This negative charge also causes natural zeolites to have little or no affinity for anions like chromate, arsenate, and nitrate. Modification of zeolites surfaces by certain surfactants was emerged as knew material for removal of anions [4]. The major shortcoming of this material is surfactants high cost. In this work instead of surfactants, modification of clinoptilolite was carried out by polyaniline. For this purpose cation exchange reaction between Na+ and anilinum cation was carried out in aqueous solution. Then incorporated anilinum cation in zeolite pores was converted to polyaniline. The prepared composite has been studied and characterized utilizing FT-IR and X-ray diffraction spectroscopy and then has been used as effective material for removing Cr(VI) from aqueous solutions