从水溶液中去除重金属使用定制双极膜电透析工艺
Samuel Bunani1,2, Gudrun Abbt-Braun1, Harald Horn1,3
1Karlsruhe Institute of Technology, Engler-Bunte-Institut, Water Chemistry and Water Technology, Engler-Bunte-Ring 9, 76131 Karlsruhe, Germany.
Molecules (Basel, Switzerland)
|April 27, 2024
概括
一种新的双极膜电透析过程有效地从水中去除有毒的重金属 (HM). 这项技术调整pH值,降低电阻,并利用膜捕获HM,为清洁水获取提供了一个有前途的解决方案.
科学领域:
- 环境科学 环境科学
- 水处理技术水处理技术
- 分析化学 分析化学
背景情况:
- 用重金属 (HM) 污染水源对公众健康和生态系统构成重大风险.
- 现有的净水方法往往难以有效和经济有效地去除各种HM污染物.
- 需要先进的技术来确保安全的饮用水和缓解人体疾病.
研究的目的:
- 调查定制双极膜电透析 (BMED) 工艺的有效性,以从水溶液中去除重金属.
- 分析操作参数的影响,如料离子强度,电位和HM类型/度对BMED性能的影响.
- 阐明在电透析过程中重金属去除和膜相互作用背后的机制.
主要方法:
- 一个定制的双极膜电透析堆被用于重金属去除实验.
- 料离子强度 (NaCl度) 的系统变化,应用电位,以及Cd2+,Co2+,Cr3+,Cu2+和Ni的初始度.
- 对料溶液pH值变化的分析,重金属物种化,膜表面分析 (SEM-EDX) 和质量平衡计算.
主要成果:
- 该BMED工艺证明有效地去除重金属,而去除效率受操作条件的影响.
- 在1.5g/L NaCl下观察到最佳性能,HM去除在度高达30mg/L和应用电位高达15V时线性增加.
- 重金属的去除顺序一般是Cd2+ > Ni2+ > Co2+ > Cu2+ > Cr3+,有证据表明HM吸附在阳离子和离子交换膜上.
结论:
- 定制双极膜电透析工艺是将重金属与水分离的高效技术.
- 该过程表现出有益的特征,包括稀释pH调整,降低电阻,并通过离子交换膜有效地去除多价值阴离子.
- 重金属的去除是通过扩散,迁移和随后的吸附在电透析膜上发生的.
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