这一脱盐新技术是由清华大学环境系博士生曹效鑫、肖康、周颖君、张潇源组成的科研团队在环境系黄霞教授、梁鹏博士的指导下完成的。其黄霞博士,其主要的研究方向包括:1.膜法水与废水处理新技术的研究与应用,2.微生物燃料电池污水净化与同步产电技术与机理,3.生物脱氮除磷新工艺及机理,4.污泥减量与资源回收技术。
ES&T是环境领域的**期刊,具有广泛的影响力,多年来影响因子在环境领域SCI中高居首位,其年度优良论文评选活动旨在向全球学者推荐本年度*具影响力的论文,入选论文须在其研究领域具有重大和长远影响。评选分为环境科学、环境技术和环境政策三大类。经过严格甄选,此次10篇*佳论文从年度发表的1400多篇论文中脱颖而出,欧洲5篇,美国4篇,中国1篇,清华大学发表的这篇文章在环境技术类文章中位居**。
在这篇文章中,研究人员首先从池塘或其他天然水域采集样品。在样品的数百万微生物中,一些**(科学家尚未确定其种类)会自动地在其细胞内产生电子和质子,并将它们转运到体外。其他**会吸收这些电子和质子,将其作为创造氢、甲烷和其他化学物质等能量物质的“燃料”。研究人员发现,使用两片特制的塑料薄膜就可以利用这些微生物所产生的能量。这种薄膜可以分离微生物产生的电子、离子或气体,让其分别流向阴极或阳极。阴极、阳极和薄膜组装在一个如同小纸巾盒一样的透明塑料盒中。在薄膜之间加入一杯池塘里的水,**就开始工作,*终可以产生纯度达90%的水。水的纯度可以根据科学或商业需要进行调整,甚至可以达到饮用水标准。微生物燃料电池可以去除水中的大部分盐分,由于该过程能够减少电力消耗,因此还可以降低水质淡化成本。
过去,微生物燃料电池通常被用于发电或以氢气或甲烷的形式储存电,这种利用微生物脱盐细胞进行盐水脱盐的新方法通过改变微生物的发电情况,可以将盐水进行淡化处理,这是人类**次把微生物燃料电池用于盐水淡化。
利用这一方法,基本上不需要输入能量;如果人为地将有机材料添加到电池中,甚至还可以产生能量,研究人员已经准备安装一个大型微生物燃料电池,计划将其产生的废水变成氢气。
原文检索:
A New Method for Water Desalination Using Microbial DesalinationCellsCurrent water desalination techniques are energy intensive and someuse membranes operated at high pressures. It is shown here thatwater desalination can be accomplished without electrical energyinput or high water pressure by using a source of organic matter asthe fuel to desalinate water. A microbial fuel cell was modified byplacing two membranes between the anode and cathode, creating amiddle chamber for water desalination between the membranes. Ananion exchange membrane was placed adjacent to the anode, and acation exchange membrane was positioned next to the cathode. Whencurrent was produced by bacteria on the anode, ionic species in themiddle chamber were transferred into the two electrode chambers,desalinating the water in the middle chamber. Proof-of-conceptexperiments for this approach, using what we call a microbialdesalination cell (MDC), was demonstrated using water at differentinitial salt concentrations (5, 20, and 35 g/L) with acetate usedas the substrate for the bacteria. The MDC produced a maximum of 2W/m2 (31 W/m3) while at the same time removing about 90% of thesalt in a single desalination cycle. As the salt was removed fromthe middle chamber the ohmic resistance of the MDC (measured usingelectrochemical impedance spectroscopy) increased from 25 Ω to 970Ω at the end of the cycle. This increased resistance was reflectedby a continuous decrease in the voltage produced over the cycle.These results demonstrate for the first time the possibility for anew method for water desalination and power production that usesonly a source of biodegradable organic matter and bacteria.