Nanoparticle-Modified Cassia Fistula Sawdust-Based G-Filters for Fluoride Removal from Drinking Water

G-filter is a common household ceramic water filter manufactured from kaolinite sawdust. Kaolinite and sawdust wet mixtures are press-formed to produce the frustum shape; air-dried and sintered to manufacture the G-filter. The sawdust used is a mixture of dissimilar wood waste readily available at carpentry workshops. In this article, Cassia fistula pods sawdust is used instead of the sawdust mixture. This new filter is named Cassia Fistula Modified (CFM) G-filter. Thermogravimetric and SEM analysis were performed to characterize and compare the CFM and regular G-filter variants. The CFM G-filter has a double modal mass reduction compared to the G-filter manufactured with sawdust as raw material. Comparative flow analysis revealed a ten-fold increase in filtration rate in CFM-based G-filters compared to regular G-filters. Therefore, CFM-modified G-filters can become a potential solution for fluoride removal from drinking water sources. The CFM greenware mixture is modified with ferric chloride and alumina nanoparticles to produce a Novel Clay Ceramic (NVC) water filter. The control experiments for NVC water filters were conducted on a G-filter modified in similar manner with FeCl3 and Al2O3 nanoparticles. Ion-selective elective test for NVC filter achieved ~33% and ~53.33% fluoride removal in the first and the second run, respectively. Similarly, ion chromatography revealed 37.66% and 46.97% fluoride removal in the first run and the second run, respectively. The regular G-filter did not showcase any specific removal whatsoever compared to the NVC. The implication of this work is the use of local plant materials as point-of-use solutions for drinking water problems.