title: Characterization of metal removal of immobilized Bacillus strain CR-7 biomass from aqueous solutions.
abstract: Bacillus strain CR-7 of multiple metal and antibiotic resistances was isolated. Its metal adsorption under different pretreatments and immobilizations from aqueous solution was characterized. Pretreatment with NaOH (0.1 mol L(-1)) significantly improved Cu(2+) adsorption capacity of the bacterial biomass. Sodium alginate (2%) was the ideal immobilization matrix. The immobilized and pretreated biomass had an obvious "orderliness", following the order of Cu(2+)>Zn(2+) in the solution containing these two metals, and following the order of Pb(2+)>Al(3+)>Cr(6+)>Cu(2+)>Fe(3+)>Zn(2+) = Ni(2+)>Cd(2+) = Co(2+)>Mn(2+) in the solution containing these 10 metals. ΔH° and ΔS° of Cu(2+) adsorption were +7.68 J/mol and +16.628 J/mol K, respectively. The infrared peak of -N-H shifted greatly after Cu(2+) adsorption. After adsorption treatment, some molecular groups disappeared in un-immobilized biomass but were still present in the immobilized biomass. Cu(2+) adsorption fit both Langmuir and Freundlich isotherm models. It was concluded (1) that the Cu(2+) adsorption process was endothermic, (2) that -N-H is a most important Cu(2+)-binding group, (3) that immobilization prevents loss or damage of the Cu(2+)-binding molecular groups, and (4) that Cu(2+) adsorption of pretreated and immobilized biomass is homogeneous.
authors.affiliation: Guangxi Key Laboratory of Subtropical Bioresource Conservation and Utilization, Nanning, Guangxi 530004, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Xu
authors.forename: Xian-Chong
authors.initials: XC
authors.lastname: Song
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Pan
authors.forename: Yu
authors.initials: Y
authors.lastname: Liang
authors.forename: Xian-Wei
authors.initials: XW
authors.lastname: Fan
authors.forename: You-Zhi
authors.initials: YZ
authors.lastname: Li
mesh_terms: D000327:Adsorption; D001407:Bacillus / Q000378:metabolism*; D001483:Base Sequence; D018533:Biomass; D017931:DNA Primers; D004352:Drug Resistance, Microbial; D008670:Metals / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D008670:Metals; D014874:Water Pollutants, Chemical