부산대학교 도서관

Keywords Bisphenol A; Loess amended organo-bentonites; Adsorption; Landfill liner; Breakthrough time Highlights * Organo-bentonite amended loess was evaluated for adsorptive removal of Bisphenol A. * Adsorption mechanisms of BPA and Pb.sup.2+ onto amended mixtures were discussed. * The cycled column tests were performed to assess the adsorption and transport of BPA. * Long-term performance of organo-bentonite amended loess is illustrated by MIM model. Abstract Bisphenol A (BPA) is a toxic endocrine disruptor often found in landfill leachate. Adsorption behaviors and mechanisms of BPA onto organo-bentonites amended loess, e.g., Hexadecyltrimethylammonium chloride-bentonite (HTMAC-B) and Carboxymethylcellulose-bentonite (CMC-B) were experimentally investigated. The adsorption capacity of loess amended by HTMAC-B (LHB) and CMC-B (LCB) is 4.2 and 4 times greater than that of loess (L), respectively. It is attributed to the increase of hydrogen bonds and hydrophobic lateral interactions between the adsorbent and the adsorbate. The binary (Pb.sup.2+-BPA) systems may enhance BPA adsorption onto the samples by the formation of coordination bonds between the hydroxyl group of BPA and Pb.sup.2+ ions. A cycled column test was used for investigating the transport behavior of BPA in LHB and LCB samples. The hydraulic conductivity of loess amended by the organo-bentonite (e.g., HTMAC-B, CMC-B) is generally lower than 1 x 10.sup.-9 m/s. Especially for CMC-B amended loess, the hydraulic conductivity can be reduced to 1 x 10.sup.-12 m/s. This guarantees the hydraulic performance of the liner system. Transport behavior of BPA in cycled column test is explained by the mobile-immobile model (MIM). Modelling results showed that loess amended by organo-bentonites can increase the breakthrough time of BPA. In comparison to loess-based liner, the breakthrough time of BPA for LHB and LCB can be increased by a factor of 10.4 and 7.5, respectively. These results indicate that organo-bentonites can serve as a potentially effective amendment for improving the adsorption of loess-based liners. Author Affiliation: (a) College of Civil Engineering and Architecture, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China (b) Center for Balance Architecture, Zhejiang University, 148 Tianmushan Road, Hangzhou, 310007, China (c) The Architectural Design and Research Institute of Zhejiang University Co. Ltd, 148 Tianmushan Rd, Hangzhou, 310058, China (d) Geoenvironmental Research Centre, Cardiff University, S Glam, Cardiff, Wales, CF24 3AA, UK * Corresponding author. Article History: Received 24 October 2022; Revised 20 February 2023; Accepted 24 February 2023 Byline: Haijian Xie (a,b), Jiawei Wu (a,c), Mengzhen Yu (a,b), Huaxiang Yan [yanhuaxiang@zju.edu.cn] (a,*), Shakil Masum (d), Peifu Cai (a,b), Yun Chen (b,c)