Enhanced adsorption capacity and selectivity toward inorganic and organic mercury ions from aqueous solution by dye‐affinity adsorbents

Abstract

Adsorption of inorganic mercury [Hg(II)] and organic methylmercury [MeHg(II)] ions onto dye‐affinity agrowaste (dye‐AW) was investigated. The dye‐affinity adsorbents were prepared by the chemical‐thermal reaction between the agrowaste (AW) and dye solutions [i.e., Reactive Red 120 (RR), Reactive Black B (RB), Methylene Blue (MB), and Methyl Orange (MO)] under an alkaline condition. An almost perfect removal of Hg(II) was observed for all adsorbents, while for MeHg(II), the dye‐affinity adsorbents have a higher removal efficiency than a pristine adsorbent. The maximum adsorption capacity (Qe, max) of mercury ions onto the Reactive Red 120‐modified AW (RR‐AW) was 2.60 mmol g−1 for Hg(II) and 0.76 mmol g−1 for MeHg(II). The adsorption rate of Hg(II) was faster than MeHg(II), and both kinetic data followed the pseudo‐second order kinetic model with the diffusion steps controlled by the film diffusion. The regenerated adsorbent showed very encouraging results especially toward Hg(II). The promising results were also obtained by using oilfield produced water (OPW) and natural gas condensate (NGC) samples. These studies finally demonstrated that the agricultural wastes initially loaded with dyes have the potential to be good mercury adsorbents. © 2018 American Institute of Chemical Engineers Environ Prog, 38: S54–S67, 2019

Squaramide-Immobilized Carbon Nanoparticles for Rapid and High-Efficiency Elimination of Anthropogenic Mercury Ions from Aquatic Systems

“…Pristine 8 behaved as hexadentate ligands to coordinate with Hg 2+ by oxygen and nitrogen atoms to form a feasible chelating complex (Figure ). , The plausible adsorption mechanism demonstrated that Hg 2+ was successfully adsorbed by the coordination interactions, electrostatic, and Lewis’s acid–base interactions between Hg 2+ and oxygen/nitrogen-bearing functional groups of 8 . In addition, Hg 2+ might have been adsorbed within pores present on the surface of 8 via electrostatic interactions with oxygen-containing functional groups of 8 (Figure ).…”

“…A similar plausible adsorption mechanism of Hg 2+ on the different adsorbents was also investigated . The thermodynamic measurements and related parameters are presented in Table S4.…”

“…A similar plausible adsorption mechanism of Hg 2+ on the different adsorbents was also investigated. 60 The thermodynamic measurements and related parameters are presented in Table S4. The ΔG°value was negative for all adsorption temperatures demonstrating that the adsorption of Hg 2+ was spontaneous.…”

Adsorption Processing for the Removal of Toxic Hg(II) from Liquid Effluents: Advances in the 2019 Year

“…Adsorption of inorganic mercury [Hg(II)] (and organic methylmercury [MeHg(II)]) onto dye-affinity agrowaste (dye-AW) was investigated [90]. The dye-affinity adsorbents were prepared by the chemical-thermal reaction between the agrowaste (AW) and dye solutions (i.e., reactive red 120 (RR), reactive black B (RB), methylene blue (MB), and methyl orange (MO)) under alkaline medium.…”