Mass transfer properties of adsorption membranes for small molecular weight substance

Abstract

【Objective】We compared the mass transfer properties of a small molecular weight substance using two types of adsorption membranes in vitro without the aid of principles such as diffusion or filtration. 【Methods】In vitro experiments were conducted using a test solution with creatinine (Cr) in a closed circuit with a polymethyl methacrylate (PMMA) (1.3 m² membrane area) and acrylonitrile-co-methallyl sulfonate surface-treated (AN69ST) (1.0 m² and 1.5 m² membrane areas) membranes as hemofilters. Regarding the experimental conditions, the test solution flow rate was set to 150 mL/min and the diffusion and filtration flow rates were not set. Samples were collected every 30 s before and after the use of the hemofilter. Cr concentrations were measured to compare the membrane materials. 【Results】Cr concentration before the use of hemofilter decreased for all three membranes: 7.6％ for the PMMA membrane and 29.9％ to 43.4％ for AN69ST membranes. 【Conclusion】In AN69ST membranes, Cr concentration decreased in a closed circuit devoid of principles such as diffusion or filtration, suggesting adsorption properties for small molecular weight substances with no electric charge.