期刊
SEPARATION AND PURIFICATION TECHNOLOGY
卷 328, 期 -, 页码 -出版社
ELSEVIER
DOI: 10.1016/j.seppur.2023.125004
关键词
Cr(VI); CDI; Pseudocapacitance; LDHs; PPy; Electrosorption
This study investigates the efficient removal of high concentrations of aqueous hexavalent chromium (Cr(VI)) using capacitive deionization (CDI) technology, through the synthesis of a pseudocapacitive NiFe-layered double hydroxide/polypyrrole (NiFe-LDH/PPy) electrode. The results demonstrate the potential of NiFe/PPy for efficient Cr(VI) removal, making it a promising approach for wastewater treatment.
The wastewater polluted by high concentrations of aqueous hexavalent chromium (Cr(VI)) has serious adverse effects on ecological environment and human health. As a burgeoning, environmental-friendly, and promising wastewater treatment technology, capacitive deionization (CDI) process for efficient removal of aqueous Cr(VI) needs to be investigated. In this work, pseudocapacitive NiFe-layered double hydroxide/ polypyrrole (NiFe-LDH/ PPy, denoted as NiFe/PPy) electrode was synthesized by the in-situ polymerization of PPy on the NiFe-LDH surface. Results of characterizations manifested that NiFe/PPy had the chain spherical structure of PPy. In particular, excellent PPy provides effective reversible capacitance and ion diffusion and improves the conductivity and pseudocapacitance performance of NiFe-LDH. Then, the NiFe/PPy anode and activated carbon (AC) cathode were assembled into the CDI cell for capacitive removal of high concentrations of aqueous Cr(VI). In 20 mL/min of flow velocity, 1.2 V, and 100 mL 100 mg/L of Cr(VI) solution, the Cr(VI) electrosorption capacity and removal ratio attained to 47.95 mg/g and 95.89%, respectively. The electrosorption of Cr(VI) slightly decreased under the common competing anions of Cl-, NO3-, SO42- , HCO3-, and CO32- . Based on Langmuir isotherm model, the maximum theoretical removal capacity of NiFe/PPy for Cr(VI) was 111 mg/g. The electrostatic attraction, reduction, and surface complexation played primary roles in the CDI system of NiFe/PPy//AC asymmetric electrodes. The outstanding electrosorption performance makes this CDI system have a favorable application prospect in the actual wastewater treatment containing high concentrations of Cr(VI).
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据