title: Biosorption of Pb(II) and Cr(III) from aqueous solutions: breakthrough curves and modeling studies.
abstract: The sorption capacity parameters obtained for batch studies provide useful information about biosorption system. However, such data fail to explain the process under continuous-flow conditions. The present study is an attempt to explore the biosorption of Pb(II) and Cr(III) by straw from local wheat (Triticum aestivum). The biosorbent has been characterized by using Fourier transform infrared spectroscopy and surface area and elemental analyses and found to be porous and polyfunctional. S-shaped breakthrough curves were obtained at different column heights for the both metal ions. Various breakthrough parameters and saturation times have been determined. The column data have been successfully used to study the Bohart-Adams' bed depth service time (BDST) model and Yoon and Nelson's model. It was found that BDST model quite efficiently explained the whole column data whereas Yoon and Nelson model could explain it below 90% breakthrough concentration. The predicted and calculated BDST parameters were in agreement with each other. Yoon and Nelson's constant decreased with an increase in the column height for both metal ions. Effect of change in flow rate on the Pb(II) biosorption has also been discussed with respect to BDST approach.
authors.affiliation: Institute of Chemistry, University of the Punjab, Lahore, Pakistan. ufq44@hotmail.com
authors.forename: Umar
authors.initials: U
authors.lastname: Farooq
authors.forename: Makshoof
authors.initials: M
authors.lastname: Athar
authors.forename: Misbahul Ain
authors.initials: MA
authors.lastname: Khan
authors.forename: Janusz A
authors.initials: JA
authors.lastname: Kozinski
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D002857:Chromium / Q000032:analysis* / Q000737:chemistry; D007700:Kinetics; D007854:Lead / Q000032:analysis* / Q000737:chemistry; D008956:Models, Chemical; D014908:Triticum / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D014874:Water Pollutants, Chemical; D002857:Chromium; D007854:Lead