Selective removal of chromium (VI) from waste water of stainless steel industry with hollow fiber supported liquid membrane

摘要

The selective and removal Cr(VI) compounds have received considerable attention, because these are extensively used for an industrial application particularly in stainless steel process. Pickling for stainless steel process is one of the main causes of contamination of the natural environment with Cr(VI) ions. In the present study, we focused on the Cr(VI) removal from spent pickling solution which contained Ni 2+ ,Fe 3+ and other metals ions by using hollow fiber supported liquid membranes. This paper examines optimum conditions for hollow fiber supported liquid membranes process used t°Cr(VI) removal from spent pickling solution. The effects of various parameters such as the concentration of Metyl trioctylammonium chloride (Aliquat336), the concentration of striping solution, the pH of stripping solution and the temperature of the system have been studied. The results showed that the percentage of extraction was highly dependent on the concentration of Aliquat336.The maximum percentage of extraction for Cr (VI) was 69% when the Aliquat336 concentration was 5 % (v/v). The influence of sodium chlorine concentration in stripping solution was found that the percentage of extraction and stripping slightly increased, respectively. The maximum percentage of stripping for Cr (VI) was 20% when the concentration of sodium chlorine 0.7 M was used. The stripping solution at pH 11, was found good response used to Cr(VI) removal from aqueous solution. The influence of the temperature (20, 30, 40, and 50.C) was found that, percentages of extraction and stripping increased at high temperature. The activation energy was evaluated 15.14 KJ/mol.