Ultrasonic irradiation of carbofuran: decomposition kinetics and reactor characterization.

The sonochemical decomposition of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl,C12H15NO3) in a parallel plate near-field acoustical processor (NAP) is reported. Ultrasonic irradiation was performed at 16 and 20 kHz, under a total applied power of 1800 W. Carbofuran decomposition was enhanced with increasing power densities (1.65 W mL-1-5.55 W mL-1), and with decreasing initial concentrations (25 microM vs. 130 microM). The nature of the dissolved gas in solution also influenced the observed decomposition rate. The hydrodynamic behavior of the NAP reactor was characterized by calculating the Reynolds numbers and by performing tracer studies with a conservative tracer, sodium chloride (NaCl). The calculated dispersion coefficients indicate an intermediate amount of dispersion during operation of the reactor.