Saurabh N. Misal, Donglin Li, Sangil Kim, Brian P. Chaplin
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引用次数: 0
Abstract
This study investigated the material and ion transport properties of TiO2 nanopores as a function of solution conditions and applied electrode potentials. Zeta potential measurements revealed that the TiO2 surface charge was highly dependent on solution conditions, which was attributed to protonation/deprotonation of surface functional groups and adsorption of ions. Ion rejection followed the absolute magnitude of the membrane surface charge and was pH-dependent, reflecting the amphoteric nature of TiO2. The rejection of NaCl was approximately symmetrical about the point of zero charge of the membrane, with the highest rejection at acidic and basic conditions. Specific adsorption of SO42– and Mg2+ under acidic and basic conditions, respectively, neutralized the membrane charge and significantly reduced ion rejection. A mathematical transport model was fit to experimental data, and the model-determined membrane charge densities as a function of solution conditions agreed with experimental zeta potential measurements. Model results also revealed that rejection was primarily attributed to the Donnan exclusion mechanism. The application of both anodic and cathodic potentials directly to the TiO2 membrane caused permselective transport under specific solution conditions.
期刊介绍:
ACS ES&T Engineering publishes impactful research and review articles across all realms of environmental technology and engineering, employing a rigorous peer-review process. As a specialized journal, it aims to provide an international platform for research and innovation, inviting contributions on materials technologies, processes, data analytics, and engineering systems that can effectively manage, protect, and remediate air, water, and soil quality, as well as treat wastes and recover resources.
The journal encourages research that supports informed decision-making within complex engineered systems and is grounded in mechanistic science and analytics, describing intricate environmental engineering systems. It considers papers presenting novel advancements, spanning from laboratory discovery to field-based application. However, case or demonstration studies lacking significant scientific advancements and technological innovations are not within its scope.
Contributions containing experimental and/or theoretical methods, rooted in engineering principles and integrated with knowledge from other disciplines, are welcomed.