title: Modeling and sensitivity analysis on the transport of aluminum oxide nanoparticles in saturated sand: effects of ionic strength, flow rate, and nanoparticle concentration.
abstract: Aluminum oxide nanoparticles have been widely used in various consumer products and there are growing concerns regarding their exposure in the environment. This study deals with the modeling, sensitivity analysis and uncertainty quantification of one-dimensional transport of nano-sized (~82 nm) aluminum oxide particles in saturated sand. The transport of aluminum oxide nanoparticles was modeled using a two-kinetic-site model with a blocking function. The modeling was done at different ionic strengths, flow rates, and nanoparticle concentrations. The two sites representing fast and slow attachments along with a blocking term yielded good agreement with the experimental results from the column studies of aluminum oxide nanoparticles. The same model was used to simulate breakthrough curves under different conditions using experimental data and calculated 95% confidence bounds of the generated breakthroughs. The sensitivity analysis results showed that slow attachment was the most sensitive parameter for high influent concentrations (e.g. 150 mg/L Al2O3) and the maximum solid phase retention capacity (related to blocking function) was the most sensitive parameter for low concentrations (e.g. 50 mg/L Al2O3).
authors.affiliation: University of Texas at San Antonio, Department of Civil and Environmental Engineering, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: Tanzina
authors.initials: T
authors.lastname: Rahman
authors.affiliation: University of Texas at San Antonio, Department of Civil and Environmental Engineering, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: Harry
authors.initials: H
authors.lastname: Millwater
authors.affiliation: University of Texas at San Antonio, Department of Civil and Environmental Engineering, One UTSA Circle, San Antonio, TX 78249, USA. Electronic address: heather.shipley@utsa.edu.
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Shipley
mesh_terms: D000537:Aluminum Oxide / Q000032:analysis* / Q000737:chemistry; D007700:Kinetics; D008956:Models, Chemical; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry; D009994:Osmolar Concentration; D012822:Silicon Dioxide / Q000737:chemistry*; D014873:Water Pollutants / Q000032:analysis* / Q000737:chemistry; D018508:Water Purification / Q000379:methods
chemical_list: D014873:Water Pollutants; D012822:Silicon Dioxide; D000537:Aluminum Oxide
keywords: Aluminum oxide; Nanoparticle; Sensitivity analysis; Transport modeling; Uncertainty quantification