Statistically Modelling for Optimizing the Removal of Heavy Metals and Escherichia Coli in Potable Water Filter

This study is to investigate the E. coli and heavy metals removal efficiency by comparing various adsorbents, including diatomite, nano titanium dioxide, Iron (II, III) oxide. Ceramic beads D composition of 60% grey clay, 20% diatomite and 20% starch (percentage by weight) showed complete removal of E. coil in the experimental testing. Ceramic beads D composition with the use of nano Fe3O4 adsorbent showed the significant removal of six types of heavy metals (Cd, Cr, Cu, Fe, Ni and Pb). The predicted results of the optimized filter B revealed that Algal-nanotechnology could shorten the treatment time by 50 seconds with 90.9% removal of E. coli and the Cu, Fe, Ni and Pb heavy metals concentration were lower than the acceptable limits of the Water Pollution Control Ordinance (Cap 358 section 21). The lead removal was investigated by the RSM evaluate the effect of initial dosage concentration and treatment time. The optimal condition with 1 mg/L or less initial Pb dosage concentration could have a complete removal after 10 seconds. This study demonstrated the optimized performance of using algal-nanotechnology in potable water treatment.