Advances in greener separation processes – case study: recovery of chlorinated aromatic compounds
Advances in greener separation processes – case study: recovery of chlorinated aromatic compounds
复制标题
DOI：
10.1039/b300062c
复制
发表时间：
2003-06
期刊：
影响因子：
9.8
通讯作者：
M. Keane
中科院分区：
文献类型：
--
作者：
M. Keane
有效的废物管理必须解决避免废物、废物再利用、废物回收以及作为最不进步的选择的废物处理问题。分离方法非常符合现代绿色处理的精神，用于从有毒废物（特别是含水）流中分离、浓缩和回收有价值的材料。概述了已建立的分离技术，重点是有机污染物和相关的补救目标。选择的案例研究是为了说明分离在环境污染控制中的作用，涉及从废水中去除有毒的氯代芳烃。这是一个日益受到关注的问题，因为政府立法的重点是大幅减少各种氯化化合物的排放。介绍和讨论了氯排放的来源和对环境的影响以及现有的处理技术。吸附是最广泛适用的无损控制技术，提供了回收/再循环的可能性。以活性炭的吸附性能为标准，对新型催化生成结构炭的性能进行了评价，结果表明，在间歇和半间歇操作中，新型催化生成结构炭的性能优于活性炭。吸收的水平是显着更高的碳表面，已通过酸洗和部分氧化功能化。当处理连续污染物流时，碳纳米丝吸附剂床表现出较低的背压，在间歇操作中液体与固体的分离更容易，并且在极性溶剂中氯代芳烃的回收/浓缩是可能的，这些因素的组合有利于更清洁的分离/再循环。
Effective waste management must address waste avoidance, waste reuse, waste recovery and, as the least progressive option, waste treatment. Separation methodologies fit well within a modern green processing ethos, serving to isolate, concentrate and recover valuable material from toxic waste (notably aqueous) streams. An overview is provided of the established separation techniques that focuses on organic contaminants and the associated remediation objectives. The Case Study chosen to illustrate the role separation has to play in environmental pollution control deals with the removal of toxic chloroarenes from wastewater. This is a topic of growing concern as governmental legislation focuses on a substantial reduction in the emission of a broad range of chlorinated compounds. The sources and environmental impact associated with chloro-emissions and the existing treatment technologies are presented and discussed. Adsorption represents the most widely applicable non-destructive control technology, offering the possibility of recovery/recycle. Taking adsorption on activated carbon as a standard, the performance of novel catalytically generated structured carbon is evaluated and shown to outperform activated carbon in batch and semi-batch operation. The level of uptake is markedly higher on carbon surfaces that have been functionalised by acid washing and partial oxidation. The carbon nanofilament adsorbent bed exhibits lower back pressures when treating a continuous contaminant flow, separation of the liquid from the solid in batch operation is more facile and a chloroarene recovery/concentration is possible in polar solvents, a combination of factors that facilitates cleaner separation/recycle.