Analysis of Nanoparticle Agglomeration in Aqueous Suspensions via Constant-Number Monte Carlo Simulation

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• 作者：Haoyang Haven Liu ; Sirikarn Surawanvijit ; Robert Rallo ; Gerassimos Orkoulas ; Yoram Cohen
• 刊名：Environmental Science & Technology
• 出版年：2011
• 出版时间：November 1, 2011
• 年：2011
• 卷：45
• 期：21
• 页码：9284-9292
• 全文大小：975K
• 年卷期：v.45,no.21(November 1, 2011)
• ISSN：1520-5851

文摘

A constant-number direct simulation Monte Carlo (DSMC) model was developed for the analysis of nanoparticle (NP) agglomeration in aqueous suspensions. The modeling approach, based on the 鈥減articles in a box鈥?simulation method, considered both particle agglomeration and gravitational settling. Particle鈥損article agglomeration probability was determined based on the classical Derjaguin鈥揕andau鈥揤erwey鈥揙verbeek (DLVO) theory and considerations of the collision frequency as impacted by Brownian motion. Model predictions were in reasonable agreement with respect to the particle size distribution and average agglomerate size when compared with dynamic light scattering (DLS) measurements for aqueous TiO₂, CeO₂, and C₆₀ nanoparticle suspensions over a wide range of pH (3鈥?0) and ionic strength (0.01鈥?56 mM). Simulations also demonstrated, in quantitative agreement with DLS measurements, that nanoparticle agglomerate size increased both with ionic strength and as the solution pH approached the isoelectric point (IEP). The present work suggests that the DSMC modeling approach, along with future use of an extended DLVO theory, has the potential for becoming a practical environmental analysis tool for predicting the agglomeration behavior of aqueous nanoparticle suspensions.