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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    ABSTRACT: BACKGROUND: In Izmir (Turkey) polyaromatic hydracarbon (PAH) removal efficiencies are low in petrochemical industry aerobic biological wastewater treatment plants because bacteria are not able to overcome the inhibition of these toxic and refractory organics. In order to increase PAHs removal, sonication process was chosen among other advanced treatment processes include sonication processes. The effects of ambient conditions, increasing sonication time, sonication temperature, TiO2 and Fe+2 concentrations on sonication at a petrochemical industry wastewater treatment plant in Izmir (Turkey) was investigated in a 650 W sonicator, at a frequency of 35 kHz and a 500 mL glass reactor.RESULTS: Increasing the temperature improved PAH removal after 150 min sonication at 30 °C and 60 °C. The maximum total PAH removal efficiencies were the same in a reactor containing 20 mg L−1 TiO2 and in a TiO2-free reactor at 30 °C and 60 °C after 150 min sonication. Maximum 91% and 97% total PAH removals were obtained in a control reactor and a reactor containing 20 mg L−1 Fe+2 at 30 °C and 60 °C, respectively, after 150 min sonication. The PAH concentration was toxic to Daphnia magna, so that the EC50 value decreased significantly from 342.56 ng mL−1 to EC50 = 9.88 ng mL−1 and to EC50 = 3.35 ng mL−1, at the lowest TiO2 (0.1 mg L−1) and Fe+2 (2 mg L−1) concentrations, respectively, after 150 min sonication at 30 °C.CONCLUSION: PAHs and the acute toxicity in a petrochemical industry wastewater were removed efficiently through sonication. Copyright © 2010 Society of Chemical Industry
    Journal of Chemical Technology & Biotechnology 03/2010; 85(7):913 - 925. · 2.50 Impact Factor
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    International journal of Advanced Engineering Research and Studies. 12/2012; 2(1):72-55.
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    RESEARCH JOURNAL OF CHEMISTRY AND ENVIRONMENT 12/2012; 16(4):192-199. · 0.64 Impact Factor