Elution profile of cationic and anionic adsorbate from exhausted adsorbent using solvent desorption

Abstract

Present invention involves to study the elution profile of anionic and cationic compounds from exhausted adsorbents using various eluents. Batch elution studies of anionic components like Congo Red dye and Carbonate ion; and cationic compounds such as Methylene blue dye and Cadmium metal from previously used naturally prepared adsorbents i.e. Gulmohar (Delonix regia) leaf powder—GLP; and Neem (Azadirachta indica) leaf powder—NLP and their derivatives were conducted. Different eluents used for batch study were various acids and alkaline solution having various concentration and solvents having different functional groups in seven sorption–desorption cycles. The batch data were accessed by kinetic models (Pseudo First-, Pseudo Second-order, Intra-particle and Elovic equation). Column elution experiments of Congo red and Cadmium from NLP and activated charcoal from NLP (AC-NLP) respectively was performed using selected eluent. Sorption and elution process plots and parameters and life cycle plots for seven sorption–desorption cycles were evaluated and discussed. From desorption efficiencies, it revealed that desorption exploration is predominately depends upon pH factor.

Fabrication of polyamide-12/cement nanocomposite and its testing for different dyes removal from aqueous solution: characterization, adsorption, and regeneration studies

“…Generally, NaOH has a higher cation exchange capacity and loses its solvation easily during the ion-exchange process. At equilibrium, the quantity of adsorbent is higher than adsorbate 102 , hence when the cations present in the exhausted PA-12/PC nanocomposite were reacted with negatively charged NaOH, the anionic CR desorbed from exhausted PA-12/PC nanocomposite due to electrostatic interaction. This observation confirms the isotherm results that adsorption is dominated by physical adsorption.…”

Adsorptive potential of ZnO/SiO2 nanorods prepared via the sol–gel method for the removal of Pb(II) and Cd(II) from petroleum refinery wastewater

“…This result confirms that an increase in the concentration of acid increases the desorption of heavy metals. However, it has been reported that a higher concentration of acid above 0.15 mol L −1 may damage the structure of the adsorbent 28 …”

“…However, it has been reported that a higher concentration of acid above 0.15 mol L −1 may damage the structure of the adsorbent. 28…”

“…Desorption can be achieved through thermal (solvent‐free) and solvent methods. The solvent desorption method is known to be environmentally friendly, inexpensive, quick, promising and has a lot of potential 28 …”

“…The solvent desorption method is known to be environmentally friendly, inexpensive, quick, promising and has a lot of potential. 28 From previous literature, the SiO 2 nanoparticles used were synthesized from chemical sources which are costly and generate secondary pollutants. The SiO 2 nanoparticles used in the study reported here were synthesized from naturally available kaolin to reduce cost.…”