title: Biosorption of uranium by chemically modified Rhodotorula glutinis.
abstract: The present paper reports the biosorption of uranium onto chemically modified yeast cells, Rhodotorula glutinis, in order to study the role played by various functional groups in the cell wall. Esterification of the carboxyl groups and methylation of the amino groups present in the cells were carried out by methanol and formaldehyde treatment, respectively. The uranium sorption capacity increased 31% for the methanol-treated biomass and 11% for the formaldehyde-treated biomass at an initial uranium concentration of 140 mg/L. The enhancement of uranium sorption capacity was investigated by Fourier transform infrared (FTIR) spectroscopy analysis, with amino and carboxyl groups were determined to be the important functional groups involved in uranium binding. The biosorption isotherms of uranium onto the raw and chemically modified biomass were also investigated with varying uranium concentrations. Langmuir and Freundlich models were well able to explain the sorption equilibrium data with satisfactory correlation coefficients higher than 0.9.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, People's Republic of China. baijing@impcas.ac.cn
authors.forename: Jing
authors.initials: J
authors.lastname: Bai
authors.forename: Huijun
authors.initials: H
authors.lastname: Yao
authors.forename: Fangli
authors.initials: F
authors.lastname: Fan
authors.forename: Maosheng
authors.initials: M
authors.lastname: Lin
authors.forename: Lina
authors.initials: L
authors.lastname: Zhang
authors.forename: Huajie
authors.initials: H
authors.lastname: Ding
authors.forename: Fuan
authors.initials: F
authors.lastname: Lei
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Wu
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Li
authors.forename: Junsheng
authors.initials: J
authors.lastname: Guo
authors.forename: Zhi
authors.initials: Z
authors.lastname: Qin
mesh_terms: D000327:Adsorption; D018533:Biomass; D004785:Environmental Pollutants / Q000378:metabolism*; D052918:Environmental Restoration and Remediation; D005557:Formaldehyde / Q000494:pharmacology; D000432:Methanol / Q000494:pharmacology; D012248:Rhodotorula / Q000187:drug effects / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared; D014501:Uranium / Q000737:chemistry / Q000378:metabolism*
chemical_list: D004785:Environmental Pollutants; D005557:Formaldehyde; D014501:Uranium; D000432:Methanol