Winburn Matthew R, Alvarado Maria F, Cheung Chin Li
Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA.
Department of Chemistry, North Central College, Naperville, Illinois, USA.
Nanoscale. 2025 Jan 23;17(4):2138-2146. doi: 10.1039/d4nr02498b.
This study addresses the critical need for the effective removal of nanoplastics (1 nm to 1000 nm), which pose a significant environmental challenge due to their ease of entry into biological systems and poorly understood health impacts. We report our investigation of a plasma-assisted methodology with a falling film plasma reactor to destroy and remove 200 nm polystyrene nanoplastic particles from their aqueous solution. Using the nanoparticle tracking analysis, size exclusion chromatography, and total organic carbon (TOC) analysis, we examined the degradation kinetics of the nanoplastics upon plasma-assisted treatment. A nanoplastic removal rate of 98.4% by particle count was achieved in one hour of treatment. This rate increased to 99.3% after three hours of treatment, along with a 27.4% reduction in the TOC of the solution. The chromatography results indicate that the observed elimination of nanoplastic contaminants was likely through the production of short polystyrene oligomers with molecular weights roughly equivalent to those of two styrene units. The superior efficacy of the plasma-assisted methodology over traditional ozonation to destroy nanoplastics was also illustrated. Our results not only elucidate a hypothesized polystyrene radical decay mechanism but also demonstrate a potential and complementary approach for mitigating nanoplastic pollution in water purification strategies.
本研究满足了有效去除纳米塑料（1纳米至1000纳米）的迫切需求，纳米塑料因其易于进入生物系统且对健康影响了解甚少而构成重大环境挑战。我们报告了我们对一种采用降膜等离子体反应器的等离子体辅助方法的研究，以从其水溶液中破坏和去除200纳米的聚苯乙烯纳米塑料颗粒。使用纳米颗粒跟踪分析、尺寸排阻色谱法和总有机碳（TOC）分析，我们研究了等离子体辅助处理后纳米塑料的降解动力学。在处理一小时后，通过颗粒计数实现了98.4%的纳米塑料去除率。处理三小时后，该去除率提高到99.3%，同时溶液的TOC降低了27.4%。色谱结果表明，观察到的纳米塑料污染物的消除可能是通过产生分子量大致相当于两个苯乙烯单元的短聚苯乙烯低聚物。还说明了等离子体辅助方法相对于传统臭氧化法在破坏纳米塑料方面的卓越功效。我们的结果不仅阐明了一种假设的聚苯乙烯自由基衰变机制，还展示了一种在水净化策略中减轻纳米塑料污染的潜在且互补的方法。
