Selective and efficient sequestration of Cr(VI) in ground water using trimethyloctadecylammonium bromide impregnated on Artemisia monosperma plant powder

Background: Biosorption method for Cr(VI) removal from domestic and industrial wastewater is widely desir- able technicality due to its high efficiency, natural affinity, selectivity, easily operation, low costs and eco- friendly procedures. The presented work demonstrates the sequestration of hexavalent chromium ion, Cr(VI) from contaminated water by the biosorbent Artemisia monosperma (AM) powder modified by trimethylocta- decylammonium bromide (TOAB).
Methods: Analytical tools of XRD, FTIR, SEM, EDS, TGA and XPS were used from one side to characterize the developed modified biosorbent TOAB@AM and from the other side to investigate the Cr(VI) adsorption. Oper- ational parameters of pH, adsorbent dose, contact time, coexisting ions and temperature that affect adsorp- tion process were optimized.
Significant Findings: Adsorption kinetics emerges the best linearity when applying the pseudo-second- order model referring to the chemisorption assumption in controlling sorption process of TOAB@AM biosorbent and Cr(VI) ions. Adsorption isothermal results are distinctly well fitted with Langmuir cor- relation. Furthermore, adsorption thermodynamics reveals the spontaneity and exothermic modality in adsorbing Cr(VI) onto TOAB@AM biosorbent with less randomness behavior. The optimal operational conditions for Cr (VI) removal are pH = 3; 0.1g dose of TOAB@AM; and 40 min contact time that result in adsorption capacity of Cr (VI) about 36.9 mg/g. Merits of low cost, high selectivity, and adsorptive potency of the novel TOAB@AM biosorbent towards Cr(VI) ions makes it a worthy alternative for reme- diating water sources from Cr(VI) contaminates within a facile and fast avenue.