Article

Using sonochemical reactor for degradation of LAS from effluent of wastewater treatment plant

Tehran University of Medical Sciences, School of Public Health, Department of Environmental Health Engineering, Center for Environmental research, Tehran, Iran; Mashhad University of Medical Sciences, School of Public Health, Department of Environmental Health, Mashhad, Iran; Tehran University of Medical Sciences, School of Public Health, Department of Epidemiology and Biostatistics, Tehran, Iran
Desalination 01/2010; DOI: 10.1016/j.desal.2009.05.011

ABSTRACT Linear alkylbenzene sulfonates (LAS) are anionic surfactants, which are found in relatively high amounts in domestic and industrial wastewaters. The effectiveness of using sonochemical reactor for the degradation of LAS from effluent of wastewater treatment plant has been investigated. In this study, experiments of LAS solution were performed using methylene blue active substances (MBAS) method. The effectiveness of sonochemical reactor for LAS degradation is evaluated with emphasis on the effect of sonication time and initial LAS concentration. Experiments were carried out at initial concentrations of 0.2 mg/L, 0.5 mg/L, 0.8 mg/L and 1 mg/L, frequency of 130 kHz, acoustic power value of 400 W, temperature of 18–20 °C and pH value of 6.8–7. This study showed that LAS degradation was found to increase with increasing sonication time. In addition, as the concentration is increased, the LAS degradation rate decreases in the sonochemical reactor.

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