(42b) Investigating the Potential of TMS-EDTA Modified Silica for Valuable Element Adsorption from Produced Water

This study investigated the potential of TMS-EDTA modified silica as an adsorbent for removing rare earth elements from produced water. Different pH values were used during the modification process, leading to the formation of TMS-EDTA on the surface of the silica. The effect of pH on the adsorption capacity of the modified silica was examined using high salinity mixtures solution containing lanthanum. FTIR was employed to characterize the modified silica, confirming the grafting of TMS-EDTA onto the surface of the silica powders. The results of zeta potential analysis demonstrated that a higher pH value during the modification process resulted in a lower negative charge on the surface of the silica, thus enhancing its capability to adsorb positively-charged ions. The modified silica with an optimum pH value of the modification process exhibited superior adsorption capacity compared to unmodified silica, exhibiting higher selectivity towards lanthanum, even in the presence of a high concentration of sodium. These findings suggest that TMS-EDTA modified silica possesses considerable potential for removing valuable components from wastewater with high salinities. The results also contribute to the growing body of research on effective strategies for the management of produced water, particularly in the context of environmental protection and resource recovery.