Kinetic, Equilibrium and Thermodynamic Studies of the Biosorption of Heay Metals by <i>Ceratonia </i><i>Si</i><i>liqua</i> Bark

Abstract

Biosorption of Zn(II), Ni(II), Cu(II) and Cd(II) ions from aqueous solutions onto Ceratonia siliqua (Carob tree) bark has been investigated in a batch biosorption process. The biosorption process was found to be dependent on pH of solution, initial metal ion concentration, biosorbent dose, contact time and temperature. The experimental equilibrium biosorption data were analyzed by Langmuir, Freundlich, Temkin and Dubinin-Radushkevic isotherm models. The Langmuir model gave a better fit than the other three models by higher correlation coefficient, R 2 . The maximum biosorption capacity calculated from the Langmuir isotherm was 42.19 mg/g, 31.35 mg/g, 21.65 mg/g and 14.27 mg/g for Ni(II), Zn(II), Cu(II) and Cd(II), respectively at optimum conditions. The kinetic studies indicated that the biosorption process of the metal ions followed well pseudo-second-order model. The negative values of ∆G o and the positive ∆H o revealed that the biosorption process was spontaneous and endothermic. According to the biosorption capacity, Ceratonia siliqua bark considered as an effective, low cost, and environmentally friendly biosorbent for the removal of metal ions ions from aqueous solutions.

Biosorption of Cu(II), Ni(II), Zn(II) and Pb(II) ions from aqueous solution by Sophora japonica pods powder

“…In recent years, the searches for low-cost agricultural by-products have been widely studied for metal ion removal from water and wastewater. These include Citrus reticulata [4], maize cob [5], Tectona grandis leaves [6], neem biomass [7], Eucalyptus camaldulensis leaves [8], rice straw [9], rice husk [10], Eucalyptus bark, mango bark and pine apple fruit peel [11], Moringa oleifera bark [12], hazelnut, almond and walnut shells [13], Pinus gerardiana leaves [14], Cynodon dactylon, Psidium guajava, Azadirachta indica, Cassia tora and Cassia angustifolia leaves [15], coconut leaves [16], Ashoka leaf [17], Ceratonia siliqua bark [18] and Eriobotrya japonica bark [19]. This paper presents the study of biosorption characteristics of Sophora japonica pods powder (Sjp) for the removal of Cu(II), Ni(II), Zn(II) and Pb(II) ions from aqueous solution in batch process.…”

Comparative biosorption of Pb2+ ions from aqueous solution using Moringa oleifera plant parts: Equilibrium, kinetics and thermodynamic studies

“…This is due to higher interaction between the metal ion and the adsorption site (Farhan et al, 2012). This trend suggests that increase in adsorbate concentration results in increase in number of available molecules per binding site of the adsorbent, thus bringing about a higher probability of binding of molecules to the adsorbent.…”

“…The n-values for all the moringa samples on Pb 2+ sorption fall in this range, therefore, the surfaces are heterogeneous. The n-values are greater than 1 which shows that the adsorptions were mainly physical processes for all the samples (Farhan et al, 2012). According to n-values in Table 3, the order of heterogeneity was increasing in the order: seeds (2.6925)>blended (2.2784)>leaves (1, 7806)>pods (1.712).…”

“…According to K F values, the order of ascending adsorption was seeds (2.6925)> blended (2.2784)> leaves (1.78)> pods (1.7120). The n-values should be in the range 1˂n˂10 to satisfy the heterogeneity condition (Farhan et al, 2012). This also implies a beneficial adsorption process.…”

CAROB (Ceratonia siliqua): HEALTH, MEDICINE, CHEMISTRY

“…Kinetics of adsorption has been presented. 137 Ethanol extract of pods was found protective against lead (Pb) poisoning in Oreochromis niloticus fish. In this report, all along the article ether extract is mentioned but in the experimental section, alcohol extraction is described.…”