Abstract
Experiments were performed to investigate the effect of operating parameters on the photodegradation efficiency of paraquat in a TiO2-suspended photoreactor with immersed UV lamps. TiO2 particles were prepared by a hydrothermal method. The removal rate of paraquat in the reactor was 0.54 mg/l/h with only air-sparging. The removal rate in 24 h with both the UV radiation and air-sparging was 50% higher than that with only the UV radiation. Variations of the paraquat concentration at the UV intensities of 4 and 8 W/m2 decreased slowly with time, but that at 12 W/m2 decreased more rapidly. The removal efficiency at the air-sparging flow rate of 1 //min increased as a UV light intensity increased. pH value in the reactor at the UV intensity of 12 W/m2 decreased with time until 12 h and then increased with time over 12 h.
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Lee, JC., Kim, MS., Kim, C.K. et al. Removal of paraquat in aqueous suspension of TiO2 in an immersed UV photoreactor. Korean J. Chem. Eng. 20, 862–868 (2003). https://doi.org/10.1007/BF02697289
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DOI: https://doi.org/10.1007/BF02697289