Microfiltration of Synthetic Bacteria Solution Using Low Cost Ceramic Membranes

Abstract

This work addresses the development and identification of optimal low cost membrane morphologies for bacteria separation applications. Using uniaxial dry compaction method, ceramic membranes (CM1–CM3) were prepared using kaolin, quartz, calcium carbonate, sodium carbonate, boric acid, sodium metasilicate, and poly-vinyl alcohol (PVA) precursors. The fabricated membranes possessed diverse pore morphologies (0.7-4.5 μm average pore size and 39.4–19.3% porosity). Amongst all membranes, the CM3 membrane with wide pore morphology (average pore size of 4.5 μm and porosity of 19.3%) provided the best performance during the direct-flow MF of synthetic Escherichia coli (DH5α strain) solutions. The CM3 membrane provided a trans-membrane flux varying from 1.21 × 10^{− 2} –3.51 × 10⁻³ m³/m².s after 10 minutes of direct-flow MF for a variation in feed concentrations of 0.004 –14.9 × 10⁶ CFU/mL. Corresponding bacterial removal efficiency and log₁₀ reduction value (LRV) values varied from 99-99.9999% and 2-6 respectively. Further, various fouling models have been evaluated for their use in measuring flux decline data. The results indicated that both membrane pore morphologies and concentration of E. coli strains significantly influenced the measured transmembrane flux, fouling index, and separation efficiency.

Keywords:

• ceramic membrane
• E. coli
• LRV
• fouling