ENVR 110 |
| In this work, we have prepared a composite styrene acrylonitrile (SAN) membrane on a ceramic clay plate using a prepolymer solution prepared using a dual initiator system. This membrane is further chemically modified by gas phase nitration followed by amination to make it charged and has been characterized by SEM, AFM, FTIR, contact angle measurement, water permeability measurement and molecular weight cut-off experiments. The SEM photographs clearly show that polymer membrane is adhered to the support surface without penetrating the ceramic support. The membrane has been further characterized using chromic acid rejection (real and observed) at different pressures and feed concentrations and was shown to possess intrinsic rejections above 90%. The experimental data has been explained through a space charge model. The solution scheme is found to be computationally intensive due to the highly nonlinear nature of the Poisson Boltzmann Equation and to facilitate the data fitting, a polynomial series solution has been developed. A procedure has been evolved to fit the experimental results by varying the concentration at the pore mouth so as to include concentration polarization effects. The root mean square error between the predicted and the experimental value has been minimized to determine the value of the wall potential which is found to be 110 mV for the quarternized membrane. |
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General Topics
2:00 PM-4:10 PM, Wednesday, August 22, 2007 Boston Park Plaza -- Beacon Hill Rm, Oral
Division of Environmental Chemistry |