Recovery of Chromium by Chemical Precipitation from Tannery Effluent

B. G. Pachpande and S. T. Ingle

School of Environmental and Earth Sciences, North Maharashtra University, Jalgaon- 425 001 (India)

The use of chromium in tanning applications is still widespread and has resulted in a serious environmental problem all over the world. The present study emphasizes on efficient removal of chromium and other contaminants (organic as well as inorganic matter) from spent chrome tanning effluent. Alkalies viz. sodium carbonate, sodium hydroxide, magnesium oxide, ammonium hydroxide and calcium oxide are used for chemical precipitation of chromium. Among the alkalies used for precipitation calcium oxide was observed efficient precipitating agent. This system of chromium reduction is useful for recovery and reuse of chromium from the waste generated in the continuous tanning process. At optimum pH for chromium (III) reduction considerable reduction in total solids, chemical oxygen demand, chlorides and sulphate of the tannery effluent was also observed.

Recovery of chromium; Tannery effluents