Patents
The invention relates to a process for recovery of chromium from wash water and combined effluent from chrome plating industry. This invention particularly relates to the extraction and recycling of the recovered chromate from the acidic industrial effluents containing hexavalent chromium by solvent extraction using trialkylphosphine oxide (cyanex 923) in kerosene. Stripping of chromate -loaded organic with very dilute alkaline distilled water and producing pure sodium chromate, which can be used in the electroplating bath of the electroplating plant. The invention uses a very dilute solvent i.e. only upto 0.0625M for recovery of pure hexavalent chromium from aqueous solutions. The raffinate solution free from hexavalent chromium can be used as rinse water. The process not only meet the strict environmental regulations but it also helps in conserving the natural resources.