Cadmium removal from aqueous solutions using biosorbent Syzygium cumini leaf powder: Kinetic and equilibrium studies

Abstract

Syzygium cumini L. leaf powder and Cd(II) loaded samples were characterized using FTIR and SEM techniques. The biosorption of cadmium ions from aqueous solution was studied in a batch adsorption system as a function of pH, contact time, adsorbate, adsorbent, anion and cation concentrations. The biosorption capacities and rates of transfer of cadmium ions onto S. cumini L. were evaluated. The kinetics could be best described by both linear and nonlinear pseudo-second order models. The isothermic data fitted to various models in the order Freundlich>Redlich-Peterson>Langmuir>Temkin. The maximum adsorption capacity of S. cumini L. leaves at room temperature was estimated to be 34.54 mg g −1 . The negative values of ∆G 0 indicated the feasibility of the adsorption process. The endothermic nature was confirmed by the positive value of the enthalpy change (∆H 0 =3.7 kJ mol −1 ). The positive value of entropy change (∆S 0 =16.87 J mol −1 K −1 ) depicted internal structural changes during the adsorption process.

Adsorption of Cadmium from Aqueous Solution by Ficus religiosa Leaf Powder and Characterization of Loaded Biosorbent

“…1). The better fitting of pseudo-second-order model as compared to the first-order-model for cation adsorption on different adsorbents has been reported by a number of researchers [13,14,[17][18][19].…”

“…Besides the agriculture wastes, leaves of various trees which are also waste and are usually dumped into garbage cans can be potential adsorbents for mitigation of heavy metal ions. Studies have been reported on dried leaf powders of various trees such as neem [10], olive [11], rubber [12], teak [13], and jamun [14] for Cd(II) adsorption from aqueous solutions. The present work is an attempt in the direction of finding an alternate, cheap, green biosorbent for treatment of effluents laden with cadmium.…”

Modeling the kinetics of Cd(II) adsorption on Syzygium cumini L leaf powder in a fixed bed mini column

“…Recently many reviews have been published highlighting use of agricultural low cost waste materials for the removal of heavy metals [8][9][10][11][12][13][14]. Some of the adsorption processes developed for removal of cadmium using biosorbents include tea waste [15,16], food waste [17], sugarcane bagasse [18], degreased coffee seeds [19], apple residue [20,21], saw dust [22][23][24], eucalyptus bark [25] mango peel waste [26], rice husk [27] and leaf powders [28][29][30][31].…”

Response Surface Optimization for Removal of Cadmium from Aqueous Solution by Waste Agricultural Biosorbent Psidium guvajava L. Leaf Powder

“…The biosorption on dried leaves is attributed to their protein, carbohydrates, and phenolic compounds which have metal binding functional groups such as carboxyl, hydroxyl, sulfate, phosphate, and amino. Many researchers have investigated usefulness of various types of leaves with or without pretreatment 10–14 for removal of Cd(II) from wastewaters.…”