Ceramic Water Filters for the Removal of Bacterial, Chemical, and Viral Contaminants

In this study, the combination of capture mechanisms in ceramic water filters (doped with hydroxyapatite and alumina) was considered for the removal of contaminants from drinking water. It was found that hydroxyapatite and alumina were conserved during the firing process of the ceramic water filters up to 950°C. The nanopores resulting from the conservation of the additives increased the specific surface area of the ceramic water filters from 3.7 to 21.0 m2·g-1. On the other hand, the microscopic pores associated with the processing of the ceramic water filters (i.e., pressing and drying) and the combustion of the sawdust reduced the filtration time from 24 to 4 h. The efficiency of the resulting filters in removing bacterial, chemical, and viral contaminants from water was investigated using E. coli, fluoride, and MS2 as model contaminants. The contaminants were found to be captured from water by trapping in the pores, substitution in the hydroxyapatite, and adsorption on the surface of alumina. Hence, the ceramic water filters incorporating hydroxyapatite and alumina combined the different capture mechanisms. They had an efficiency of 99.998%, 99.970%, and 99.450% in the removal of bacterial, chemical, and viral contaminants, corresponding to log reduction values (LRVs) of 4.69, 3.47, and 2.26, respectively.