A Prospect for Environmental Remediation of Perchlorate via Cost-Effective Pinus Leaves and Dandelion Flower Powder-based Layer Double Hydride (LDH) Sorbents

In this study, pine leaves powder (PiP) and dandelion flower powder (DFP) were repurposed to synthesize layered double hydroxides (LDHs) to form a base for sorbents used in perchlorate remediation from wastewater. The effects of the adsorbent dose, pH, thermodynamics, and coexisting ions were evaluated in batch experiments. The results revealed that 0.1 g adsorbent (PiP-LDH and DFP-LDH) removed 97% and 93% of perchlorate contaminants, respectively. In this study, the correlation coefficient of pseudo-second-order was higher than pseudo-first-order for all the LDHs. The kinetic and isotherm studies showed the best uptake of perchlorate in the short time was by PiP-LDH, followed by DFP-LDH (20 min and 40 min, respectively). The calculated and experimental values of adsorption at the equilibrium state also concurred with the pseudo-second-order model. The prepared LDHs were mesoporous. The surface area of PiP-LDH provided more adsorption sites, rendering it more suitable for perchlorate adsorption compared with the other two LDHs. The model suggests Physico-chemical interactions behind the sorption of perchlorate by LDHs. The adsorption was more influenced by anions i.e, PO43- > SO42- > NO3 than monovalent anions due to the increase in the charge radius values. The prepared LDHs could be of great benefit to the environmental remediation of wastewater bodies. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of King Saud University.