Degrade naphthalene using cells immobilized combining with low-intensity ultrasonic technique.

In this paper, we studied the naphthalene degradation by using Pseudomonas aeruginosa under low-intensity ultrasonic stimulation. In our experiment, the degradation rate of naphthalene was the main parameter. We found that low-intensity ultrasonic could not only promote the growth of immobilized P. aeruginosa, but also could improve the degradation of naphthalene. In this article, 1% naphthalene was added into MM culture medium as imitation wastewater. The effect of low-intensity ultrasonic parameter and gel-globes size were considered. We found the influence was obvious, and the optimum degradation rate was acquired when the parameters of ultrasonic are: frequency, 24 kHz; power, 8 W; ultrasonic time, interval time, 10 s; total time, 10 m and the gel-globes were made by using injector no. 14. The naphthalene degradation rate of immobilized cells with ultrasonic stimulation is 82%, which is 12.9 and 42.2% higher than that of immobilized cells and suspended cells without ultrasonic stimulation, respectively.