Adsorption kinetics, isotherms, and thermodynamic studies for Hg²⁺ adsorption from aqueous medium using alizarin red-S-loaded amberlite IRA-400 resin

Abstract

A B S T R A C TAlizarin red-S-modified amberlite IRA-400 resin (ARSA) was applied for Hg 2+ removal from the aqueous medium which is a highly toxic metal ion. The adsorption process which was pH dependent, showed maximum adsorption of Hg 2+ in the pH range 6-8. ARSA exhibited good monolayer adsorption capacity for Hg 2+ (303.03 mg g −1 ) at 25˚C and the isotherm was well fitted by the Langmuir model. Moreover, the adsorption was evaluated thermodynamically and the negative values of Gibbs free energy revealed the spontaneity of adsorption process. The practical applicability of ARSA was explored for the adsorption of Hg 2+ metal ion from a real water sample. The values of ΔH and ΔS were found to be 79.87 kJ mol −1 and 0.26 J mol −1 K −1 , respectively.

Fabrication and characterization of a nanocomposite hydrogel for combined photocatalytic degradation of a mixture of malachite green and fast green dye

“…5d, e. Thus, it reveals that the degradation of the two dyes follows pseudo-first-order kinetics [52]. Rate constant of 0.0102 and 0.0019 min -1 was observed for malachite green and fast green dye, respectively.…”

Efficient removal of toxic phosphate anions from aqueous environment using pectin based quaternary amino anion exchanger

“…is the concentration of phosphate in the solution at equilibrium and qm (mg g -1 ) and KL (L mg -1 ) denotes the Langmuir constants related to adsorption capacity and adsorption energy, respectively [64,65]. The constants KL and qm can be calculated from slope and intercept of linear plot of Ce/qe vs. Ce as shown in the Fig.7 (a)…”

Adsorptive removal of Remazol Brilliant Blue R dye from its aqueous solution by activated charcoal of Thuja orientalis leaves: an eco-friendly approach

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