title: Grape waste as a biosorbent for removing Cr(VI) from aqueous solution.
abstract: Grape waste generated in wine production is a cellulosic material rich in polyphenolic compounds which exhibits a high affinity for heavy metal ions. An adsorption gel was prepared from grape waste by cross-linking with concentrated sulfuric acid. It was characterized and utilized for the removal of Cr(VI) from synthetic aqueous solution. Adsorption tests were conducted in batch mode to study the effects of pH, contact time and adsorption isotherm of Cr(VI), which followed the Langmuir type adsorption and exhibited a maximum loading capacity of 1.91 mol/kg at pH 4. The adsorption of different metal ions like Cr(VI), Cr(III), Fe(III), Zn(II), Cd(II) and Pb(II) from aqueous solution at different pH values 1-5 has also been investigated. The cross-linked grape waste gel was found to selectively adsorb Cr(VI) over other metal ions tested. The results suggest that cross-linked grape waste gel has high possibility to be used as effective adsorbent for Cr(VI) removal.
authors.affiliation: Department of Applied Chemistry, Saga University, Honjo 1, Saga 840-8502, Japan.
authors.forename: Rumi
authors.initials: R
authors.lastname: Chand
authors.forename: Kenji
authors.initials: K
authors.lastname: Narimura
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Kawakita
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ohto
authors.forename: Takanori
authors.initials: T
authors.lastname: Watari
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Inoue
mesh_terms: D000327:Adsorption; D002857:Chromium / Q000737:chemistry* / Q000302:isolation & purification*; D005782:Gels / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000032:analysis*; D015394:Molecular Structure; D012996:Solutions; D017550:Spectroscopy, Fourier Transform Infrared; D013997:Time Factors; D027843:Vitis / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D005782:Gels; D007220:Industrial Waste; D012996:Solutions; D002857:Chromium