Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States.
Environ Sci Technol. 2012 Feb 7;46(3):1556-64. doi: 10.1021/es203607d. Epub 2012 Jan 19.
The performance of an electrochemical multiwalled carbon nanotube (EC-MWNT) filter toward virus removal and inactivation in the presence of natural organic matter was systematically evaluated over a wide range of solution chemistries. Viral removal and inactivation were markedly enhanced by applying DC voltage in the presence of alginate and Suwannee River natural organic matter (SRNOM). Application of 2 or 3 V resulted in complete (5.8 to 7.4 log) removal and significant inactivation of MS2 viral particles in the presence of 5 mg L(-1) of SRNOM or 1 mg L(-1) of alginate. The EC-MWNT filter consistently maintained high performance over a wide range of solution pH and ionic strengths. The underlying mechanisms of enhanced viral removal and inactivation were further elucidated through EC-MWNT filtration experiments using carboxyl latex nanoparticles. We conclude that enhanced virus removal is attributed to the increased viral particle transport due to the applied external electric field and the attractive electrostatic interactions between the viral particles and the anodic MWNTs. The adsorbed viral particles on the MWNT surface are then inactivated through direct surface oxidation. Minimal fouling of the EC-MWNT filter was observed, even after 4-h filter runs with solutions containing 10 mg L(-1) of natural organic matter and 1 mM CaCl(2). Our results suggest that the EC-MWNT filter has a potential for use as a high performance point-of-use device for the removal of viruses from natural and contaminated waters with minimal power requirements.
在存在天然有机物的情况下，电化学多壁碳纳米管（EC-MWNT）过滤器对病毒去除和失活的性能在广泛的溶液化学范围内得到了系统评估。在存在藻酸盐和苏万尼河天然有机物（SRNOM）的情况下施加直流电压可显著提高病毒的去除和失活效率。在存在 5mg/L 的 SRNOM 或 1mg/L 的藻酸盐的情况下，施加 2 或 3V 的电压可导致 MS2 病毒颗粒完全（5.8 至 7.4 对数）去除和显著失活。EC-MWNT 过滤器在广泛的溶液 pH 值和离子强度范围内始终保持高性能。通过使用羧基胶乳纳米粒子进行 EC-MWNT 过滤实验，进一步阐明了增强病毒去除和失活的潜在机制。我们得出结论，增强的病毒去除归因于由于施加的外部电场导致的病毒颗粒迁移增加，以及病毒颗粒和阳极 MWNTs 之间的吸引力静电相互作用。然后，吸附在 MWNT 表面上的病毒颗粒通过直接表面氧化而失活。即使在含有 10mg/L 天然有机物和 1mM CaCl2 的溶液中进行了 4 小时的过滤器运行，EC-MWNT 过滤器的污染也很少。我们的结果表明，EC-MWNT 过滤器具有作为从天然和污染水中去除病毒的高性能即用型装置的潜力，所需功率最小。
