Development of a point-of-use water filtration system using a catalytic ceramic membrane coated with iron oxide

Abstract

Access to safe and clean water is a challenge especially in developing countries. Consumption of water contaminated with heavy metals causes health problems such as brain damage, kidney and liver failure. Point of Use (PoU) ceramic water filters are cheap and easy to use method of water treatment. In this study, six PoU ceramic water filters were made by mixing clay powders and rice husk powder in predetermined varying proportions, firing of the ceramic filters was done and then coated with 300g of iron oxide and 100ml of phytic acid. The system was used to remove heavy metals such as; zinc, lead, cadmium, manganese, copper, chromium, iron, nickel from water. The turbidity, total suspended solids, conductivity and pH levels of the influent and effluent water was determined. The results showed that; heavy metal removal was high for the coated ceramic membranes as it produced 98.73% when compared to the uncoated ceramic membranes which produced 74.11%. The study also revealed that uncoated ceramic membrane CM-3U produced the highest turbidity reduction of 81.08% while coated membranes CM-3C produced the lowest reduction of 22.97%. This was attributed to leaching of the iron oxide during the filtration process. The measured pH values ranged from 6.65 to 7.34 for the influent water samples for both the uncoated and coated ceramic membranes. This range is recommended for drinking water by world health organization. Therefore, the coated ceramic membranes exhibited a high-performance level of heavy metal removal when compared to the uncoated ceramic membrane.