Novel biosynthesized silver nanoparticles from cobweb as adsorbent for Rhodamine B: equilibrium isotherm, kinetic and thermodynamic studies

Applied Water Science

Luqmon Azeez¹  Segun A. Adebisi¹  Abdulrasaq O. Oyedeji²  Agbaje Lateef³ 

[1] Department of Chemical Sciences, Osun State University;Department of Science Laboratory Technology, Federal Polytechnic Ilaro;Nanotechnology Research Group (NANO+), Laboratory of Industrial Microbiology and Nanobiotechnology, Department of Pure and Applied Biology, Ladoke Akintola University of Technology;

关键词: Biosynthesized AgNPs;    Chemosorption;    Adsorption isotherm;    pH point of zero charge;    Spontaneity of adsorption;    Wastewater;   

DOI  :  10.1007/s13201-018-0676-z

来源: DOAJ

【 摘 要 】

Abstract This study has investigated the adsorption of Rhodamine B (Rh-B) dye on novel biosynthesized silver nanoparticles (AgNPs) from cobweb. The effects of contact time, initial pH, initial dye concentration, adsorbent dosage and temperature were studied on the removal of Rh-B and they significantly affected its uptake. Adsorption isotherms were evaluated using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The adsorption process was best described by Langmuir isotherm with R 2 of 0.9901, indicating monolayer adsorption. The maximum adsorption capacity (q max) of 59.85 mg/g showed that it has relatively high performance, while adsorption intensity showed a favourable adsorption process. Pseudo-second-order kinetics fitted best the rate of adsorption and intra-particle diffusion revealed both surface adsorption and intra-particle diffusion-controlled adsorption process. Negative values of thermodynamic parameters (∆H°, ∆S° and ∆G°) indicated an exothermic and spontaneous adsorption process. The mean sorption energy (E) and activation energy (E a) suggested the uptake of Rh-B onto AgNPs was chemical in nature (chemosorption).

【 授权许可】

Unknown