Eco-friendly removal of phosphate from aqueous solution using natural dietary fibers and minerals

Abstract

In this study, we focused on the investigation of phosphate removal using calcium oxide (CaO) and calcium hydroxide (Ca(OH)2) which are mainly from the calcined shells as adsorbents. Hydroxylapatite Ca[Formula: see text](PO4)6(OH)2, the component of industrial fertilizer was formed after the adsorption process following the XRD results. The phosphate removal increased from 20% to 97% with the aid of the mixture of flocculants alginic acid (AA), NaHCO3 and CaCl[Formula: see text] 2H2O in the case of 50 ppm phosphate concentration when the samples were filtered through 2.7 [Formula: see text]m particle retention filter paper which is roughly equivalent to the case of phosphate removal rate of 0.2 [Formula: see text]m membrane filter paper without flocculants (99%). The results suggest that AA, NaHCO3 and CaCl[Formula: see text]2H2O as the flocculants are effective for phosphate removal from 20 to 100 ppm.