An experimental study was undertaken to investigate the chemical effects of high intensity ultrasonic radiation on cyanide solutions. The effects of aeration, concentration of cyanide and temperatures on the reaction rate are investigated. The experiment was preformed in a 30 mm pyrex tube immersed at a fixed height in a constant volume water bath. Ultrasonic energy was applied through the use of a transducer epoxied at the bottom of the water bath. The power inputs to the transducer were 40W (27KHz) and 100W (21KHz).
At a power of 40W, ultrasound had no chemical effect on cyanide solutions. At 100W, hydrogen peroxide formed during the process and reacted with the cyanide. The mechanism of reaction is assumed to include both oxidation and hydrolysis of the cyanide in solution. However, the catalytic effect of hydrogen peroxide under these (conditions increased leading to substantial hydrolysis of cyanide.
As a result, the overall reaction yield increased by, 200 - 300% over the yield normally obtained from equal amounts of hydrogen per oxide in conventional cyanide - peroxide reactions.
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