Mathematical Modelling of Molecular Separation Processes in Aggressive Solvent Systems

Abstract

Abstract Research works on membrane technology, particularly molecular separation in solvent-based systems, has increased tremendously in recent years. In order to apply this technology at industrial scale, a suitable mathematical model for process design and optimisation must be developed. In the present study, mathematical models to describe process performance were developed with different levels of complexities. The models were developed based on two general transport mechanisms, pore-flow and solution-diffusion principles. Models with different complexity levels were developed, ranging from simple process models to a combination of transport, mass transfer and osmotic pressure effects. Series of molecular separation experiments were conducted to validate the models and to compare the difference among all models. The experimental system conducted in this study was a mixture of organic dyes in n-Dimethylformamide (DMF) solution, which mimics a typical industrial application where molecular purification in aggressive organic solvent is required. The filtration results obtained from any mathematical models are in good agreement with the experiments. The calculated purity of the organic dyes in the permeate ranging from 99.72 % to 100 % in comparison to 99.76 % from the experiments at 8000 s. The results obtained from this study can potentially be applied for industrial application as a prediction tool without conducting any excessive experiments.