Method for removing cyanide compounds from wastewater

摘要

The invention pertains to a method for reduction of the cyanide content of a metals-containing wastewater fraction by contacting a wastewater fraction comprising cyanide compounds and metal compounds, with a metals content of at least 100 ppm, with hydrogen peroxide and a solid catalyst comprising at least 50 wt.% of a copper salt with a solubility of less than 10 exp(-5) mol/liter (in water at 20°C, 1 atm). It has been found that when a solid catalyst comprising at least 50 wt.% of a copper salt with a solubility of less than 10 exp(-5) mol/liter (in water at 20°C, 1 atm) is used in combination with hydrogen peroxide in the reduction of the cyanide content of a cyanide compound-containing wastewater fraction having a metal compound content of at least 100 ppm, a method is obtained which shows an efficient removal of cyanide compounds from a difficult to treat fraction.