title: Kinetics and isotherms of Neutral Red adsorption on peanut husk.
abstract: Adsorption of Neutral Red (NR) onto peanut husk in aqueous solutions was investigated at 295 K. Experiments were carried out as function of pH, adsorbent dosage, contact time, and initial concentration. The equilibrium adsorption data were analyzed by Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, and Toth isotherm models. The results indicated that the Toth and Langmuir models provided the best correlation of the experimental data. The adsorption capacity of peanut husk for the removal of NR was determined with the Langmuir and found to be 37.5 mg/g at 295 K. The adsorption kinetic data were modeled using the pseudo-first order, pseudo-second order, and intra-particle diffusion kinetic equations. It was seen that the pseudo-first order and pseudo-second order kinetic equations could describe the adsorption kinetics. The intraparticle diffusion model was also used to express the adsorption process at the two-step stage. It was implied that peanut husk may be suitable as adsorbent material for adsorption of NR from aqueous solutions.
authors.affiliation: Department of Chemistry, Zhengzhou University, Zhengzhou 450052, China. rphan67@zzu.edu.cn
authors.forename: Runping
authors.initials: R
authors.lastname: Han
authors.forename: Pan
authors.initials: P
authors.lastname: Han
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Cai
authors.forename: Zhenhui
authors.initials: Z
authors.lastname: Zhao
authors.forename: Mingsheng
authors.initials: M
authors.lastname: Tang
mesh_terms: D000327:Adsorption; D010367:Arachis / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009499:Neutral Red / Q000737:chemistry*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D014874:Water Pollutants, Chemical; D009499:Neutral Red