Arsenate and Dichromate Removal Efficiency of a New Calix[4]arene Impregnated Resin

Abstract

This article highlights a newly synthesized 5,11,17,23-tetra-tert.butyl-25,26,27,28-tetrakis(hydrazidecarbonylmethoxy)-calix[4]arene (3) impregnated resin 4 and it's sorption ability for the removal of selected oxoanions, i.e., (arsenate and dichromate) from aqueous environment. Resin 4 was characterized by using FT-IR spectroscopy, scanning electron microscope (SEM), elemental, and thermogravimetic (TGA) analyses techniques. Sorption study was carried out through static and dynamic methods with continuous flow operation to evaluate the potency of resin 4 under various conditions. Several parameters, such as effect of sorbent dosage, contact time, pH, and initial concentration were optimized through batch experiments. Results justify that % sorption of these oxoanions is highly dependent on pH of the solution. Equilibrium was achieved in 45 min, while sorption efficiency of resin 4 can be better explained by Langmuir and Temkin isotherm models. Furthermore, kinetically both oxoanions follow pseudo second order model. Additionally, sorption of arsenate more appropriately could be explained by Moris-Weber diffusion kinetic model. For the dynamic method, Thomas model was used to calculate the kinetic coefficient (k TH ) and maximum sorption capacity (q o ) of resin 4 which are 3.84 and 5.94 ml mg −1 min −1 and 0.185, 0.160 mg g −1 for As (V) and Cr (VI) respectively. Furthermore, resin 4 has been found as potential sorbent for removal of these oxoanions from contaminated surface water samples.

Simultaneous removal of As(V) and Cr(VI) from water by macroporous anion exchanger supported nanoscale hydrous ferric oxide composite

“…The adsorbed amount of As(V) had a peak at about pH 7.1-7.7, while the that of Cr(VI) gradually decreased with increasing pH. The above observation agreed well with those reported in the previous studies for As (V) and Cr(VI) adsorption (Seki et al, 2005;Memon and Bhatti, 2014).…”

Recovery and Separation of Metal Ions from Aqueous Solutions by Solvent‐Impregnated Resins

“…Occasionally, Temkin [146,147] and Flory-Huggins models [84] were also studied for metal adsorption by SIRs. The Temkin isotherm equation is defined as:…”