One-pot synthesis of Fe(III)-coordinated diamino-functionalized mesoporous silica: Effect of functionalization degrees on structures and phosphate adsorption

Abstract

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Kinetics, isotherm, thermodynamic, and adsorption mechanism studies of La(OH) 3 -modified exfoliated vermiculites as highly efficient phosphate adsorbents

“…2.0 mL of suspension was taken out, filtered and analyzed over a given period of time t. The phosphate desorption ratio was estimated by, (16) where C t is the phosphate concentration in filtrate over a given period of time (mg P/L); q e is the adsorbed phosphate amount on the spent adsorbent at the adsorption−desorption equilibrium (mg P/g); V is the volume of NaOH solution (L) and m is the mass of spent adsorbent (g), respectively.…”

“…However, the presence of excessive phosphate in water body induces eutrophication, which causes the overgrowth of algae, lack of dissolved oxygen, reduction of water quality, and depopulation of aquatic animals. Therefore, a great deal of effort has been devoted toward the development of various adsorbents to reduce and control the concentration of phosphate in wastewater via adsorption mechanism [15,16]. The use of natural clays as phosphate adsorbents has been studied in recent years [17,18], but always limited by their low adsorption capacity to phosphate ions.…”

Porous Pr(OH)3 nanowires as novel high-performance adsorbents for phosphate removal

“…H 2 PO 4 − , HPO 4 2− , and PO 4 3− , greatly depending on the solution pH [25,51]. At the pH ranging from 2.13 to 7.20, the main species in solution is monovalent ion, H 2 PO 4 − ; whilst in the pH range of 7.20 and 11.0, HPO 4 2− is the predominant species of phosphate.…”

“…Motivated by our previous work in the field of phosphate adsorption [18,[25][26][27], we reported the phosphate removal with the utilization of porous 1D Pr(OH) 3 NWs, which were fabricated via electrochemical deposition, for the first time herein. Their phosphate adsorption isotherms and kinetics were investigated in detail.…”

Fabrication of Fe-coordinated diamino-functionalized SBA-15 with hierarchical porosity for phosphate removal

“…For instance, the Fe(III)-coordinated diamino-functionalized SBA-15 exhibited the maximum phosphate capture capacity of 20.7 mg P/g and reached almost 90% of the final adsorption capacity in 10 min [4].…”