The use of the advanced oxidation process in the ozone + hydrogen peroxide system for the removal of cyanide from water Original Research Article

The results of laboratory tests are presented in this paper, which demonstrate a possibility of using the advanced oxidation process for the removal of cyanide from the water. A comparative analysis was carried out for the processes of ozonation, oxidation with hydrogen peroxide and advanced oxidation in the O3 + H2O2 system. The paper presents experimental test results that indicate a very clear effect of the value of pH on the efficiency of the ozonation process. The performed tests have confirmed an increase in cyanide reduction with increasing reaction of water treated. This may suggest a higher susceptibility of cyanide to indirect oxidation by hydroxyl radicals than to direct oxidation by ozone. In this connection, tests were carried out on the use of advanced oxidation methods for the removal of cyanide. These methods are based on the generation of hydroxyl radicals being the most active reagents. In most processes, •OH radicals are produced with the help of an oxidant added. In view of the fact that hydrogen peroxide is used for waste-water treatment, the tests were carried out for the O3 + H2O2 system. The paper gives optimal ozone doses in conjunction with hydrogen peroxide for water prepared with a cyanide solution. The effect of oxidizer dosing order of on the reduction of cyanide is described.