Alternatives to hypochlorite treatment for destruction of cyanide in effluent water.

Abstract

This study focuses on the treatment of cyanide containing wastewater from a chemical process for cyanide liquor manufacture. An introduction to cyanide is given including legislation and governmental controls in place for Britain and the works. The effluent treatment system at present uses sodium hypochlorite and there are low concentrations of chloroform formed within the system, which then remains untreated. This study summaries the array methods for cyanide degradation currently available and evaluates the most promising for the sites cyanide wastewater treatment. The appraisal highlights the potential of using hydrogen peroxide and sonication in unison to rapidly degrade the high cyanide content of the wastewater. Experimental laboratory results show that sonication rapidly increases the reaction potential of the hydrogen peroxide. Sonication was shown, by statistical analysis (Tukey) to have a significant effect on cyanide reduction compared with hydrogen peroxide alone. This study emphasises the issues of working with hydrogen peroxide and the basics of sonication. It also describes a pilot study that could be carried out in the future and the changes that may be required for this system to be put in place at the work.