Development of sodium alginate@ZnFe-LDHs functionalized beads: Adsorption properties and mechanistic behaviour of phosphate and nitrate ions from the aqueous environment

Abstract

Phosphate and nitrate are the vital micro-nutrients and a substantial contributor to the growth of biomass, energy storage, and agricultural activities. However, in their increased concentrations, they also cause potential health problems to human and all other living beings. Layered double hydroxides (LDHs) are highly selective and efficient material for the remediation of the ions of phosphate and nitrate from water, but agglomerate easily due to their high surface properties and are difficult to recover from aqueous solutions. The preparation of LDHs functionalized beads of the biopolymeric background is an alternative to overcome these difficulties. Herein, the present work examined the adsorptive removal of the above-mentioned toxic ions from water using ZnFe-LDHs assembled alginate (ZnFe-LDHs@Alg) beads. The removal efficiency and percentage were examined along with various influencing factors like sorbent dosage, solution pH, contact time, and co-ions also carried out. ZnFe-LDHs@Alg beads revealed an extreme removal efficiency of 94.64 and 74.12 mg/g for the ions of phosphate and nitrate, respectively. The phosphate and nitrate removal by ZnFe-LDHs@Alg beads showed reliability with the Freundlich isotherms. The above findings suggested that ZnFe-LDHs@Alg beads can be used as an efficient and selective sorbent for the remediation of toxic ions from water/ wastewater.

Keywords

• Adsorption
• Beads
• Characterization
• Kinetics
• Isotherm