In the present work, the sonochemical degradation of 2,4-dinitrophenol (DNP) has been investigated using two different configurations, namely, axially vibrating ultrasonic horn (20 kHz, 100 W) and ultrasonic horn with radial vibrations (36 kHz, 150 W). Calorimetric studies have been carried out to quantify the actual power dissipated into the system. Comparison of ultrasonic configurations has been done on the basis of unified criteria of cavitational yield (extent of degradation of DNP per unit supplied power). The effect of process intensifying additives such as hydrogen peroxide, ferrous ion activated sodium persulfate, and carbon tetrachloride on the extent of degradation of DNP using these reactor. configurations has also been investigated. Also the effect of combined processes such as US/Fenton and US/advanced Fenton process on the extent of degradation has been investigated. It has been observed that the ultrasonic horn with radial vibrations is more energy efficient and also gives high degree of intensification for the use of process intensifying additives as compared to the axially vibrating ultrasonic horn due to uniform distribution of cavitational activity. Theoretical studies based on the bubble dynamics simulations have also confirmed the uniformity of the cavitational activity. The kinetic analysis for the degradation process revealed that DNP degradation follows first order.