Performances Study of Polyvinylidene Fluoride (PVDF)/Waste Eggshell (WES) Mixed-Matrix Membrane for Copper Removal

Abstract

The presence of heavy metals in water resources brings hazard to health and the environment considering that most of these cannot be degraded and may result in bioaccumulation in the food chain. This study investigated the applicability and efficiency of waste eggshells for the removal of Copper (Cu) heavy metal in aqueous solution. The mixed-matrix membrane with polyvinylidene fluoride (PVDF) as membrane material, N-Methyl-2-pyrrolidone (NMP) as solvent and waste eggshell as additive with ratio of (a) 15:85:0, (b) 14.9:85:0.1, (c) 14.7:85:0.3, (d) 14.5:85:0.5 and (e) 14:85:1 is fabricated using phase inversion method. Phase inversion is a well-studied immersion precipitation technique for membrane synthesis. Using this common method, polymer is dissolved in an organic solvent and the solution cast upon a glass surface with 0.40 knife gap. The resulting membrane morphologies were analysed by using Scanning Electron Microscopy (SEM) and the significant functional group of the resulting membranes were identified using Fourier Transform Infrared Spectroscopy (FTIR). The addition of waste eggshell to the casting solution improved the morphology and structure of the membrane significantly. The appearance of waste eggshell on membrane surface demonstrated in SEM and FTIR analysis. Furthermore, the result of the study showed that the waste eggshells as an adsorbent could remove Cu in an aqueous solution up to 99% with water permeability of 56.52 Lm-2h-1bar-1. Overall, the study demonstrated that the waste eggshell that is generally considered as wastes in large quantities could become an economically advantageous for Cu removal.