Fundamental understanding of irradiation intensity and other process parameters on photocatalytic degradation of phenol in hollow fiber mixed matrix membrane

Abstract

Lack of comprehensive general theoretical model on photocatalytic mixed-matrix-membrane (PMMM) makes its practical application infeasible. The dynamic process involves bulk and porous fluid-flow; bulk convection–diffusion, interfacial adsorptive-reactive mass transport. All-inclusive first-principle based two-dimensional transient model with the continuity, momentum transport and convective-diffusive-adsorption-reaction equations are solved numerically. Experimental validation was taken up for phenol removal from synthetic solution using PMMM hollow fibres with titanium-di-oxide nanoparticle. The validated model were used to predict the performance at various light intensity (I) and feed concentrations (c0) in long-term successfully for three different cases of PMMMs. For the chosen case of PMMM, minimum I and maximum transmembrane pressure (TMP) with variable c0 for safe permeate were determined. The ‘safe operating conditions’ is the favourable operating conditions that generates permeate stream featuring a contaminant concentration under the safe discharge limit for a substantial period of time. For futuristic PMMM, a thorough parameter study was undertaken. The optimum TMP for minimum energy cost for scale-up were calculated interrelating with cross flow rates. Volume run-down was determined at safe operating conditions. This comprehensive theoretical framework can be implemented as groundwork to design present or futuristic hollow fiber PMMMs.