DECOMPOSITION OF 4-NITROPHENOL BY OZONATION IN A HOLLOW FIBER MEMBRANE REACTOR

Abstract

Abstract The effect of initial pH, liquid flow rate, gas flow rate, and gaseous ozone concentration on the ozonation of 4-nitrophenol in a membrane reactor was investigated. The results showed that the disappearance of 4-nitrophenol increased with the increase of liquid flow rate, gas flow rate, and gaseous ozone concentration. The rise of the initial pH value led to an increase in 4-nitrophenol removal rate, but the increase became negligible after initial pH exceeded 9.5. The highest removal efficiency of 4-nitrophenol achieved was 94% after 100 min reaction when gaseous ozone concentration was 0.51 mmol L−1, gas flow rate was 57 mL min−1, liquid recirculation rate was 72 mL min−1, and initial pH was 10.3. The membrane reaction system could be modeled based on the lumped kinetics of 4-nitrophenol removal, and the corresponding rate constant of 4-nitrophenol removal was determined from the model. Keywords: 4-NitrophenolHollow fiber membrane reactorLumped modelOzone Acknowledgments This study was support by Natural Science Foundation of Hubei Province, China (Grant No. 2002AB0058). Notes a The figures following the "±" signs are 95% confidence intervals.