Removal of lead from aqueous solutions and wastewaters using water hyacinth (Eichhornia crassipes) roots

Abstract

Dried ground roots of water hyacinth (Eichhornia crassipes) were used for removal of Pb(II) from aqueous solution. Batch adsorption experiments were conducted with the dried roots (0.1 g dry weight) using 100 mg/L of Pb(II) aqueous solution adjusted at pH 5.0. Equilibrium was obtained in 90 min with a 92% removal of Pb(II). The effect of contact time, pH, adsorbent dosage, initial metal ion concentration on the adsorption of Pb(II) were also studied. Kinetic studies indicated that the adsorption of Pb(II) followed the pseudo-second-order model with a reaction rate constant (k) of 0.0127 mg/(g.min). Kinetics data conforming to the pseudo-second-order model suggest that chemisorption was the rate-limiting step in the adsorption process. The adsorption data were found to fit best into the Langmuir model (R2 = 0.986). The maximum adsorption capacity was found to be ∼50 mg Pb(II) per g of dried roots. To investigate the feasibility of using the water hyacinth roots in a more realistic situation, wastewaters collected from various sources were also tested with the biosorbent. Significant removal of Pb(II) (∼88% to ∼100%) was observed from the wastewaters at pH 5.0. High adsorption capacity, rapid kinetics, and its low cost make water hyacinth dried roots a good candidate for the removal of Pb(II) from wastewaters.

Comparative Phytoremediation Potential of Eichhornia crassipes, Lemna minor, and Pistia stratiotes in Two Treatment Facilities in Cluj County, Romania

“…For example, nitrogen and phosphorus are present in high amounts in municipal wastewater, and if recovered, they can be used as bioenergy, fertilizers, and in the production of chemicals [1,5]. High bioaccumulation activities can also be achieved using dried plant material such as roots [63]. Moreover, at the end of the vegetative period of plants when the phytoremediation capacity has ended, the exhausted biomass can be used in the recovery of metals, for example, through incineration or in biogas production, using anaerobic fermentation [64].…”

Application of Water Hyacinth Biomass (Eichhornia crassipes) as an Adsorbent for Methylene Blue Dye from Aqueous Medium: Kinetic and Isothermal Study

“…5 demonstrates that the experimental data were adjusted to the pseudo-secondorder model, both for the systems using the leaf adsorbent and the stem, which obtained linearity coefficients R 2 = 0.99996 (Figure 5b,d). This model assumes that the rate-determining step depends on the physicochemical interactions between the adsorbate and the adsorbent surface groups, thus indicating a chemisorption process [66,67].…”

“…Several authors found results adjusted to the pseudo-second-order model using bioadsorbents. For example, Jahangiri et al [67] worked on Pb(II) lead removal from aqueous solutions and wastewater using water hyacinth (Eichhornia crassipes) roots. The kinetic data indicated that Pb(II) adsorption followed the pseudo-second-order model with a reaction rate constant (K) of 0.0127 (mg.g −1 .min −1 ).…”

“…Jahangiri et al [67] performed isothermal tests using water hyacinth (Eichhornia crassipes) roots to remove lead from aqueous solutions and wastewater. The values described the best result for Langmuir (R 2 = 0.986), and the maximum adsorption capacity was 50 mg•g −1 Pb(II) of dry roots.…”

Adsorption of chromium from electroplating wastewater using activated carbon developed from water hyacinth

“…Conventional wastewater treatment processes are not sufficiently eliminated heavy metals including Cr [ 18 ]. But, advanced water treatment technologies such as membrane separation processes, advanced oxidation processes, ozonation, adsorption, and membrane bioreactors achieved high Cr removal [ 6 , 19 – 21 ]. Recently, advanced wastewater treatment technologies are considered the state of the art in heavy metal removal [ 22 ].…”