Removal of Pb(II) from aqueous solutions by Phytolacca americana L. biomass as a low cost biosorbent

Abstract

Screening a new biosorbent with low cost and high efficiency from a native plant material is a key to the adsorption of heavy metal ions from wastewater. In this study, the potential of Phytolacca americana L. as a biosorbent for Pb(II) removal from aqueous solutions was investigated. Experiments were performed to evaluate the effect of biosorbent dosage, pH, initial Pb(II) concentration and contact time on the Pb(II) removal. The results indicated that the hydroxyl, carboxyl and amine groups may take part in Pb(II) binding. HNO 3 -modified P. americana (HPAL) showed a significant higher uptake capacity compared to original P. americana (PAL) (p < 0.05). A dose of 20 g L À1 of biosorbents in solutions with an initial pH of 6.0, an initial Pb(II) concentration of 30 mg L À1 and a contact time of 120 min resulted in the maximum Pb(II) removal efficiency. The Freundlich isotherm gave a better fit than the Langmuir isotherm revealed that the biosorption was potentially multilayer. Further, the adsorption kinetics followed a pseudo second-order model, which implied that the biosorption was mainly a chemisorption process. The thermodynamic properties showed that the Pb(II) adsorption onto the P. americana biomass was feasible, spontaneous and exothermic in nature. Both physisorption and chemisorption were involved in the biosorption of Pb(II) onto the surface of P. americana biomass through electrostatic interaction and ion exchange. Additionally, desorption studies revealed promising regeneration potential of these biosorbents. The present study showed that P. americana biomass could be used

Biosorption of lead (II) from an aqueous solution using biosorbents prepared from water plants

“…While the other two biosorbents showed a bit of increasing removal stabilizing at 4 and 5 g/l dosages. Similar trend was observed in other studies that with increase of biosorbent dosage the biosorption efficiency decreased [35]. Increasing amount of biosorbent in solution caused biosorbents to combine with each other and larger particles were formed, which resulted in the decrease of biosorption potential as well as surface area.…”

Kinetics and isothermal modeling of liquid phase adsorption of rhodamine B onto urea modified Raphia hookerie epicarp

“…Texture of the adsorbent may have been altered by microwave irradiation (Foo and Hameed 2009). Hollows, pores, and cavities are important in solid-liquid adsorption, serving as transport paths for adsorbate movement (Wang et al 2015). However, after RhB uptake, the smooth surfaces of the adsorbents were observed to be rough, and the visible openings scarcely exist (Fig.…”

Heavy Metal Lead Removal by Biosorption – A Review

“…The functionalized Saccharomyces cerevisiae cell with biogenic intracellular CaCO3 mineral scaffold was efficient for removing Pb(II) ions from aqueous solutions at the maximum removal capacity of 116.69 mg g −1 [27]. HNO3 modified Phytolacca americana was found to have higher uptake capacity than the original P. americana [28]. The different lead removal capacities of several biosorbents under optimum conditions are summarized in table I.…”