title: Co-transport of Pb(2+) and TiO2 nanoparticles in repacked homogeneous soil columns under saturation condition: Effect of ionic strength and fulvic acid.
abstract: This study investigated the effects of suspended TiO2 nanoparticles (nTiO2) on the transport of Pb(2+) in saturated repacked soil columns under different ionic strengths (IS) and in the presence of fulvic acid (FA). Also, the contribution of soil colloids to the mobility of Pb(2+) was discussed. In the absence of nTiO2, little amount of Pb(2+) was detected in the effluent even in the presence of FA. However, the presence of nTiO2 significantly enhanced the mobility of Pb(2+) in soil columns under all tested conditions and nTiO2-associated Pb(2+) was the major migration species of Pb(2+). Increasing the solution IS decreased the nTiO2-associated Pb(2+) migration due to the significant decrease in the mobility of nTiO2 in soil. FA remarkably increased the nTiO2-associated Pb(2+) mobility in soil column, which was mainly to increase the mobility of nTiO2 in soil and decrease desorption rate of Pb(2+) from nTiO2 during transport. Moreover, nTiO2 significantly enhanced the release of Fe-Al soil colloids, which in turn was also responsible for the enhancement of Pb(2+) mobility in soil.
authors.affiliation: School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, PR China. Electronic address: rceesfangjing@126.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Fang
authors.affiliation: School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, PR China.
authors.forename: Keke
authors.initials: K
authors.lastname: Zhang
authors.affiliation: School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, PR China.
authors.forename: Peide
authors.initials: P
authors.lastname: Sun
authors.affiliation: Department of Environmental Science, Zhejiang University, Hangzhou 310058, PR China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Daohui
authors.initials: D
authors.lastname: Lin
authors.affiliation: School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, PR China; Department of Environmental Science, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Bing
authors.initials: B
authors.lastname: Shen
authors.affiliation: Environment Protection Research and Design Institute of Ningbo, 315012, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Luo
keywords: Fulvic acid; Pb(2+); Soil; TiO(2) nanoparticles; Transport