Investigation of Heavy Metals Removal from Aqueous Solutions by Ceramic Filters

— The study utilized the membrane filtration technique to remove two common heavy metals from aqueous solutions; the first was Pb+2, and the second was Cd+2. Manufacturing of ceramic filters was carried out through the dimensions of 20 by 20 cm and thickness of 4 cm from local clay and sawdust at different percentages of sawdust: 1.0%, 2.5%, and 4.0%. The study examined the key factors affecting the removal efficiency of the ceramic filters, such as the initial pH value (5.5 and 7.0) and initial concentration (5.0 and 10.0 mg/L) of heavy metals at a constant pressure head of 30 cm. Moreover, the study applied a microstructural analysis using the scanning electronic microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) on the utilized ceramic membranes before and after the filtration process. The results showed that the percentages of heavy metals removal are more than 80% at pH 5.5 and 82% at pH 7.0. The efficiency of removing heavy metals from aqueous solutions declines as the initial metal concentrations increases while it increases with the applied water head. Further, although the sawdust percentages had a slight effect on the removal efficiency, ceramic filters with a sawdust percentage of 1.0% were the best.