Micro-encapsulation and hydrothermal tuning of amine decorated magnetic alginate hybrid beads for nitrate and phosphate remediation

The magnetic iron oxide (Fe3O4)/alginate (Alg) (MAIg) composite beads were synthesized and utilized for the nitrate (NO3-) and phosphate (PO43-) retention. To enhance the functional behaviour and sorption capacity of MAIg composite beads, the amine groups were grafted to get the amine functionalized MAlg (AFMAlg) composite beads via, in situ precipitation (In situ) and hydrothermal (Hydro) techniques. The hydro assisted AFMAlg composite beads hold the unique advantages like high porous nature and large surface area than the other adsorbents prepared by in situ method for NO3- and PO43- removal. Several characterization studies such as XRD, FTIR, SEM, VSM, BET and EDAX analysis were explored. The parameters responsible for sorption process like contact time, solution pH, co-anions, adsorbent dosage, initial adsorbate concentration and temperature were optimized in batch scale. The nature of NO3- and PO43- sorption was verified by fitting the experimental data with various isotherms, kinetics and thermodynamic parameters. The field applicability and regeneration studies of the AFMAlg composite beads were also performed. (C) 2019 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.