Affiliation:
1. Department of Chemistry Dr. Harisingh Gour University Sagar Madhya Pradesh India
2. School of Applied Material Sciences Central University of Gujarat Gandhinagar Gujarat India
Abstract
AbstractA novel α‐manganese dioxide/β‐dicalcium silicate (α‐MnO2/β‐C2S) nanocomposite was synthesized for adsorption of phosphate ions from water to inhibit eutrophication. The adsorption rate constants (k2) of α‐MnO2/β‐C2S nanocomposite are higher than those of bare α‐MnO2 and β‐C2S revealing an increased adsorption rate in composite materials. The higher adsorption capacity of nanocomposites results from relatively larger pores. The phosphate sorption process obeys the pseudo‐second‐order kinetic model well and is likely governed by chemisorption. The equilibrium removal capacities of α‐MnO2, β‐C2S, and α‐MnO2/β‐C2S nanocomposite were found to be 25, 34.48, and 52.63 mg/g, respectively, which are very close to experimental values. Adsorption of PO43− onto adsorbents could be favorably described by the Langmuir model. D‐R isotherm model fitting showed physical adsorption by β‐C2S and α‐MnO2/β‐C2S nanocomposites and chemisorption on α‐MnO2. The maximum adsorption capacities (qm) of the adsorbents calculated from the Langmuir model were 28.58, 44.03, and 63.65 mg/g α‐MnO2, β‐C2S, and α‐MnO2/β‐C2S nanocomposites respectively. The thermodynamic parameters showed that the adsorption process occurs spontaneously with an exothermic nature and a decrease in randomness. The presence of coexisting Cl− anions decreases the adsorption capacity.
Subject
Materials Chemistry,Marketing,Condensed Matter Physics,Ceramics and Composites