A potential-controlled ion pump based on a three-dimensional PPy@GO membrane for separating dilute lead ions from wastewater. (10th May 2017)

• Record Type: Journal Article
• Authors: Gao, Fengfeng; Du, Xiao; Hao, Xiaogang; Li, Shasha; Zheng, Junlan; Yang, Yanyan; Han, Nianchen; Guan, Guoqing
• Is Part Of: Electrochimica acta. Volume 236(2017)
• Page Start: 434
• Page End: 442
• Publication Date: 2017-05-10
• Subjects: electrochemically switched ion permselectivity -- three-dimensional PPy@GO membrane -- Pb2+ separation -- potential-controlled ion pump system; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2017.03.187
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Highlights: A novel potential-controlled ion pump transport mechanism was proposed for an ESIP system. 3D PPy@GO membrane exhibited excellent permselectivity for Pb 2+ . A high Pb 2+ flux was obtained due to the coupling effect of the cell voltage and pulse potential. The current efficiency of the ESIP system reached 51.9%. Abstract: A three-dimensional (3D) polypyrrole (PPy)@graphene oxide (GO) composite membrane was developed for the continuous separation of dilute Pb 2+ from wastewater in a novel potential-controlled ion pump system based on an electrochemically switched ion permselectivity (ESIP) method. The 3D PPy@GO composite membrane was fabricated via a simple one-step electrochemical co-deposition way in an aqueous electrolyte solution using a stainless steel wire mesh (SSWM) as the conductive substrate. In this system, the directional uptake/release of Pb 2+ was realized by modulating the redox state of the PPy@GO membrane and coupling it with an external electric field. The coupling of the pulse potential and cell potential formed a novel potential-controlled ion pump system which controlled the transport of Pb 2+ . The permselectivity of the 3D PPy@GO membrane and the effects of the cell potential, pulse width, pulse potential and initial concentration on the Pb 2+ flux were investigated. The 3D PPy@GO composite coated electrodes showed excellent permselectivity of Pb 2+ with a flux of 4.7 g m −2 h −1, a current efficiency of 51.9% and excellent cycling stability. The Pb 2+ concentration was reduced from 20 ppm in the source solution to 0.8 ppm with a removal percentage of 96%. This 3D PPy@GO membrane-based ESIP system could be used as a novel technique for wastewater treatment.