An Efficient Recovery of Chromium From Tanning Liquor waste and its Reutilization for the Production of Quality Leather

The conventional methods for the treatment of tannery effluents are highly expensive due to the presence of large amount of chemicals used in the processing and their environmental toxicity. In this study, chromium has been recovered from tanning waste liquor which is discarded usually in the open streams. This tanning liquor has been treated with different concentrations of alkalies such as sodium hydroxide (NaOH), ferric chloride (FeCl3) and magnesium oxide (MgO) to recover chromium using the precipitation method. The precipitation of chromium at controlled range of pH by MgO yielded the well concentrated sludge resulting the total dissolved solids in low quantity in the supernatant when compared with the other two treatments (NaOH and FeCl3). The prepared chromium sulphate liquors from recovered chrome cake has been employed at similar conditions parallel to fresh basic chromium sulphate to determine the effects on quality of leather. The resulted leathers showed almost very good properties e.g. shrinkage, tear strength, tensile strength, bursting strength, fullness, grain smoothness, etc