Diclofenac Removal and Fouling Behaviour of Multi-Channel Mixed Matrix Membranes (MCMMM) with Activated Carbon

Abstract

Anthropogenic micropollutants represent a major threat to the environment and more efficient removal processes are required. Drawbacks in the isolated application of either activated carbon or membrane technology resulted in this study where activated carbon is embedded into the matrix of a multi-channel membrane. The successful fabrication of such multi-channel mixed matrix membranes (MCMMM) from different main polymers (PES and PVDF) in a steam-dry-wet spinning process was complemented with diclofenac (DCF) removal rates of up to 65 % after 60 min. The compatibility of the filler material with the membrane matrix was variable: The PES support structure seemed to disintegrate with the addition of >2 % AC, whereas PVDF showed better interaction with the filler and burst pressures of >3.5 bar. Humic acid filtration with PVDF-based MCMMM and 3 % AC added to the spinning solution showed a reduction of the normalized flux by 24 % - a slight improvement compared to 29 % reduction in the case of the pristine PVDF membrane. The fouling behaviour could be described with a semi-empirical model. Altogether, MCMMM are a promising approach for the efficient removal of micropollutants.