抄録
Ultrasonic degradation of methylene blue (MB) in aqueous solution has been studied with the simultaneous gas bubbling as well as metal oxide addition. Varieties of gases, including argon, oxygen, nitrogen, CO_2, propane and mixture of Ar and other gas, and oxides, e.g., SiO_2, TiO_2 and Al_2O_3, have been examined. Process parameters, such as gas composition as well as oxide concentration have been optimized. The addition of 30 vol% oxygen to argon exhibited the increase of 10 % in the apparent zero-order degradation rate in comparison to that with pure Ar bubbling. This can be due to the formation of highly oxidative species in MB solution. The degradation rate increased further by 10 % by the addition of 2 g/L of aluminium oxide into MB solution.
