title: Eriobotrya japonica seed biocomposite efficiency for copper adsorption: Isotherms, kinetics, thermodynamic and desorption studies.
abstract: Adsorption techniques are widely used to remove pollutants from wastewater; however, composites are gaining more importance due to their excellent adsorption properties. Bentonite composite with Eriobotrya japonica seed was prepared and used for the adsorption of copper (Cu) metal from aqueous media. The process variables such as pH, Cu(II) ions initial concentration, adsorbent dose, contact time and temperature were optimized for maximum Cu(II) adsorption. At pH 5, adsorbent dose 0.1 g, contact time 45 min, Cu(II) ions initial concentration 75 mg/L and temperature 45 °C, maximum Cu(II) adsorption was achieved. Desorption studies revealed that biocomposite is recyclable. Langmuir, Freundlich and Harkins-Jura isotherms as well as pseudo-first and pseudo-second-order kinetics models were applied to understand the adsorption mechanism. Thermodynamic parameters (ΔG(0), ΔH(0) and ΔS(0)) suggest that the adsorption process was spontaneous and endothermic in nature. The pseudo-second-order kinetic model and Langmuir isotherm fitted well to the adsorption data. Results showed that biocomposite was more efficient for Cu(II) adsorption in comparison to individuals native Eriobotrya japonica seed biomass and Na-bentonite.
authors.affiliation: Department of Chemistry, University of Agriculture, Faisalabad 38000, Pakistan.
authors.forename: Mehwish
authors.initials: M
authors.lastname: Mushtaq
authors.affiliation: Department of Chemistry, University of Agriculture, Faisalabad 38000, Pakistan. Electronic address: hnbhatti2005@yahoo.com.
authors.forename: Haq Nawaz
authors.initials: HN
authors.lastname: Bhatti
authors.affiliation: Department of Chemistry, Qurtuba University of Science and Information Technology, Peshawar 25100, KPK, Pakistan. Electronic address: bosalvee@yahoo.com.
authors.forename: Munawar
authors.initials: M
authors.lastname: Iqbal
authors.affiliation: Department of Chemistry, University of Agriculture, Faisalabad 38000, Pakistan.
authors.forename: Saima
authors.initials: S
authors.lastname: Noreen
mesh_terms: D000327:Adsorption; D001546:Bentonite / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D031983:Eriobotrya / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008962:Models, Theoretical; D012639:Seeds / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000032:analysis; D018508:Water Purification
chemical_list: D014874:Water Pollutants, Chemical; D001546:Bentonite; D003300:Copper
keywords: Bentonite; Copper ions; Eriobotrya japonica; Isotherms; Kinetics; Thermodynamic