Sonolytic degradation of methyl tert-butyl ether: the role of coupled fenton process and persulphate ion

The sonolytic degradation of methyl tert-butyl ether (MTBE) has been investigated at ultrasonic frequency of 20 kHz. The observed pseudo-first-order rate constant decreased from 1.25×10 −4 to 5.32×10 −5 s −1as the concentration of MTBE increased from 2.84×10 −2 to 2.84×10 −1 mM. The rate of degradation of MTBE increased with the increase of the power density of ultrasonicator and also with the rise in reactor system temperature. In the presence of oxidising agent, potassium persulphate, the sonolytic rate of degradation of MTBE was accelerated substantially. Tert-butyl formate (TBF) and acetone were found to be the major intermediates of the degradation of MTBE. It is found that the ultrasound/Fe 2+/H 2O 2 method is promising process for the degradation of MTBE. More than 95% degradation of MTBE (2.84×10 −2 mM) along with its intermediate products has been achieved during the coupled ultrasound/Fe 2+/H 2O 2 method. Hence, the coupled ultrasound/Fe 2+/H 2O 2 may be a viable method for the degradation MTBE within a short period of time than the ultrasound irradiation process only. A kinetic model, based on the initial rates of degradation of MTBE and TBF, provides a good agreement with the experimental results.