Treatment of wastewater containing arsenic using Rhazya stricta as a new adsorbent

Abstract

The effective removal of heavy metals from aqueous wastes is among the most important issues for many industrialized countries. Removal of arsenic (As) from aqueous solutions was studied using Rhazia stricta biomass. The batch experiments are carried out to investigate the effect of the significant process parameters such as pH, contact time, solute concentration and adsorbent dose. The optimum pH required for maximum adsorption was found to be 5. The equilibrium data for the adsorption of As(V) on R. stricta are tested with various adsorption isotherm models such as Langmuir, Freundlich, Tempkin and Generalized equation. Results indicate the following order to fit the isotherm: Langmuir (1 and 2) > Tempkin > Generalized form > Freundlich. A comparison of two kinetic models showed that our data fitted well to the Elovich model.

Review on Biosorption of Arsenic From Contaminated Water

“…The correlation coefficients ( R 2 > 0.94) were higher compared to correlation coefficients obtained for the pseudo‐first order model. Thus, it reveals the applicability of the Elovich model to the experimental data .…”

“…: where q e is the amount of As adsorbed (mg g −1 ), T is the absolute temperature ( K ) and R is the universal gas constant, 8.314 J mol −1 K −1 . The constant b T is related to the heat of adsorption, A T is the equilibrium binding constant (L min −1 ) corresponding to the maximum binding energy, and C e is the equilibrium concentration (mg L −1 ) .…”

“…2, such as zeolite [77,80], chitosan beads [76,79], magnetite nanoparticles [74], iron-oxide coated natural rock [75], other geological adsorbents like lignite, bentonite, shale, and iron sand [78], submerged plant Hydrilla verticilata [108], certain bacterial, and fungal species like Bacillus cereus [112,134], Saccharomyces cerevisiae [111], Rhodococcus sp. [135], Staphylococcus xylosus [90], fruit and plant waste like orange peels [115], Rhazia sticta herb [117], Moringa oleifera [122], herbal dye waste of Rosa rosa [119], industrial waste (hematite) [85] have been found to be best fit with the Langmuir model for the adsorption of As.…”

“…where q e is the amount of As adsorbed (mg g À1 ), T is the absolute temperature (K) and R is the universal gas constant, 8.314 J mol À1 K À1 . The constant b T is related to the heat of adsorption, A T is the equilibrium binding constant (L min À1 ) corresponding to the maximum binding energy, and C e is the equilibrium concentration (mg L À1 ) [117]. The adsorption of As(V) on R. stricta biomass was analyzed with various adsorption isotherm models such as Langmuir, Freundlich, Temkin, and generalized equation.…”

Adsorption of β-Carotene in Isopropyl Alcohol with Decolorized Activated Carbon as Model for β-Carotene Adsorption in Crude Palm Oil

“…Langmuir equation was based on the assumption that maximum adsorption corresponds to a saturated monolayer of solute on specific homogenous sites of the adsorbent surface containing a finite number of identical sites. The energy of adsorption was constant, and there was no transmigration of the adsorbate in the plane of the surface [25].…”