Abstract:
ABSTRACT
Recovery of chromium from tannery wastewater is attractive not only environmentally but also economically. Waste waters containing Chromium Ill were oxidized in alkaline conditions with three aqueous oxidants i.e. Hydrogen Peroxide, Sodium Hypochlorite and Calcium Hypochlorite to solublize chromate. Hydrogen Peroxide was potentially a suitable oxidant as it could oxidize a suspension of Cr (OH)3 to chromate up to 98% (in synthetic solution) and 88% (in wastewater). The percentage recovery by the hypochlorites was lower than those by hydrogen peroxide. For all the three oxidants, complete recovery could not be achieved despite varying experimental conditions (temperatures and oxidation time). The amount of chromate recovered was determined by spectrophotometry and results clearly indicate that hydrogen peroxide is the most efficient among the three oxidants used.
Ground water samples from the Industrial area Sialkot (study area) were collected and analyzed for physiochemical, major anions and metal analysis to note the impact of tanneries pollution on ground aquifer. The samples were collected from tube wells and under ground storage tanks and transported to IESE, NUST laboratory for analysis. It was observed that concentration of some heavy metals were slightly higher than the normal, especially Chromium. However other physiochemical and major anions values were well within the limits laid down by WHO
