A novel bioactive foam emulsion bioreactor for benzene,toluene and xylene(BTX)contaminated air streams treatment has been developed.The gas-liquid interfacial area by biocompatible foam and driving force for mass tran...A novel bioactive foam emulsion bioreactor for benzene,toluene and xylene(BTX)contaminated air streams treatment has been developed.The gas-liquid interfacial area by biocompatible foam and driving force for mass transfer by a water immiscible organic phase were increased in this reactor.The effect of several parameters such as gas residence time,oxygen content,and organic phase concentration on bioreactor performance was studied. Experimental results showed an average elimination capacity(EC)of 220 g·m3·h -1with removal efficiency(RE) of 89.59%for BTX inlet concentration of 1 g·m3at 15 s gas residence time in the bioreactor.The statistical developed model predicted that the maximum elimination capacity of the reactor for BTX could be reached to 423.45 g·m3·h -1.Continues operation of the bioreactor with high EC and RE was demonstrated by optimizing the operational parameters of the bioreactor.Overall the results suggest that the bioreactor developed can be very effective systems to treat BTX vapors.展开更多
Magnetic ion exchange(MIEX) resins have received considerable attention in drinking water treatment due to their fast and efficient removal of dissolved organic carbon(DOC). Two types of mechanisms, i.e., ion exchange...Magnetic ion exchange(MIEX) resins have received considerable attention in drinking water treatment due to their fast and efficient removal of dissolved organic carbon(DOC). Two types of mechanisms, i.e., ion exchange,reversible and irreversible adsorption, may occur during pollutants removal by MIEX. This work examined the removal mechanism of 17α-Ethinylestradiol(EE2) by MIEX. As one of typical estrogen micro-pollutants,EE2 existed as neutral molecule in natural water, and its charge density was close to zero [(0.00000219 ±0.00000015) meq·(μg EE2)^(-1)] based on the potentiometric titration method. However, the removal of EE2 by MIEX was much higher than that of other micro-pollutants previously reported. Multi-cycle adsorptionregeneration experiments and ion exchange stoichiometry analysis were conducted to elucidate the removal mechanism of EE2 by MIEX resin. The results suggested that the main removal mechanism of EE2 by MIEX was ion exchange instead of reversible micro-pore adsorption. The experimental analysis based on Donnan theory indicated that the internal micro-environment of resin beads was alkaline, in the alkaline environment EE2 would be ionized into negatively charged groups. As a result, ion exchange reaction occurred inside the pore of MIEX resin, and the removal process of EE2 by MIEX was dominated by the ion exchange reaction.展开更多
文摘A novel bioactive foam emulsion bioreactor for benzene,toluene and xylene(BTX)contaminated air streams treatment has been developed.The gas-liquid interfacial area by biocompatible foam and driving force for mass transfer by a water immiscible organic phase were increased in this reactor.The effect of several parameters such as gas residence time,oxygen content,and organic phase concentration on bioreactor performance was studied. Experimental results showed an average elimination capacity(EC)of 220 g·m3·h -1with removal efficiency(RE) of 89.59%for BTX inlet concentration of 1 g·m3at 15 s gas residence time in the bioreactor.The statistical developed model predicted that the maximum elimination capacity of the reactor for BTX could be reached to 423.45 g·m3·h -1.Continues operation of the bioreactor with high EC and RE was demonstrated by optimizing the operational parameters of the bioreactor.Overall the results suggest that the bioreactor developed can be very effective systems to treat BTX vapors.
基金Supported by the National Natural Science Foundation of China(51678408,51478314,51638011)the National Key Research and Development Program of China(2016YFC0400506)+1 种基金the Natural Science Foundation of Tianjin(14JCQNJC09000)the Research Fund of Tianjin Key Laboratory of Aquatic Science and Technology(TJKLASTZD-2016-06)
文摘Magnetic ion exchange(MIEX) resins have received considerable attention in drinking water treatment due to their fast and efficient removal of dissolved organic carbon(DOC). Two types of mechanisms, i.e., ion exchange,reversible and irreversible adsorption, may occur during pollutants removal by MIEX. This work examined the removal mechanism of 17α-Ethinylestradiol(EE2) by MIEX. As one of typical estrogen micro-pollutants,EE2 existed as neutral molecule in natural water, and its charge density was close to zero [(0.00000219 ±0.00000015) meq·(μg EE2)^(-1)] based on the potentiometric titration method. However, the removal of EE2 by MIEX was much higher than that of other micro-pollutants previously reported. Multi-cycle adsorptionregeneration experiments and ion exchange stoichiometry analysis were conducted to elucidate the removal mechanism of EE2 by MIEX resin. The results suggested that the main removal mechanism of EE2 by MIEX was ion exchange instead of reversible micro-pore adsorption. The experimental analysis based on Donnan theory indicated that the internal micro-environment of resin beads was alkaline, in the alkaline environment EE2 would be ionized into negatively charged groups. As a result, ion exchange reaction occurred inside the pore of MIEX resin, and the removal process of EE2 by MIEX was dominated by the ion exchange reaction.
