Volume 7 Issue 2 - July 2016

  • 1. Minimization of total chromium from effluent of metal finishing industry

    Authors : Shirin Imam

    Pages : 471-474

    DOI : http://dx.doi.org/10.21172/1.72.573

    Keywords : Keywords: hexavalent chromium, chemical transformation, electroplating, spectrophotometer.

    Abstract :

    ABSTRACT- Focusing on the present scenario of water pollution the author of this paper wish to suggest an experimental and economic idea of industrial effluent treatment6. Chromium is one of the toxic heavy metal present in effluent of Electroplating2,10 industry. Hexavalent chromium is a known carcinogen and a designated hazardous pollutant5.The study was undertaken to investigate the removal of total chromium (both hexavalent and Trivalent) from waste water of Electroplating industry employing chemical treatment method, in order to bring down the concentration of chromium up to permissible limit.Chromium present in hexavalent form was reduced to trivalent form by using reducing agent’s viz.; sodium metabisulphite and ferrous sulphate. The dependency of reduction on pH was studied, a decrease in reaction rate with an increase in pH from1.0 to 5.0 was observed. It was found that proper combination of chromium reduction followed by precipitation method yielded waste water that can meet the discharge limits.Precipitation was done using lime under certain pH condition at which the solubility of metal is minimum. In case of chromium; its solubility is less when pH is around 7.5 - 8. The pH is controlled by addition of lime which is required to be added for precipitation. Thus lime plays a very important role in chemical treatment of waste generated in electroplating units.

    Citing this Journal Article :

    Shirin Imam, "Minimization of total chromium from effluent of metal finishing industry", Volume 7 Issue 2 - July 2016, 471-474