Iron oxidation and precipitation of ferric hydroxysulfates by resting Thiobacillus ferrooxidans cells

Journal Article · Wed Mar 31 23:00:00 EST 1982 · Appl. Environ. Microbiol.; (United States)

OSTI ID:5433895

Lazaroff, N; Sigal, W; Wasserman, A

The oxidation of ferrous ions, in acid solution, by resting suspensions of Thiobacillus ferrooxidans produced sediments consisting of crystalline jarosites, amorphous ferric hydroxysulfates, or both. These products differed conspicuously in chemical composition and infrared spectra from precipitates formed by abiotic oxidation under similar conditions. The amorphous sediments, produced by bacterial oxidation, exhibited a distinctive fibroporous microstructure when examined by scanning electron microscopy. Infrared spectra indicated outersphere coordination of Fe(III) by sulfate ions, as well as inner-sphere coordination by water molecules and bridging hydroxo groups. In the presence of excess sulfate and appropriate monovalent cations, jarosites, instead of amorphous ferric hydroxysulfates, precipitated from bacterially oxidized iron solutions. It is proposed that the jarositic precipitates result from the conversion of outer-sphere (T/sub d/) sulfate, present in a soluble polymeric Fe(III) complex, to inner-sphere (C/sub 3//sub v/) bridging sulfate. The amorphous precipitates result from the further polymerization of hydroxo-linked iron octahedra and charge stabilized aggregation of the resulting iron complexes in solution. This view was supported by observations that bacterially oxidized iron solutions gave rise to either amorphous or jarositic sediments in response to ionic environments imposed after oxidation had been completed and the bacteria had been removed by filtration.

• Research Organization: State Univ. of New York, Binghamton
• OSTI ID: 5433895
• Journal Information: Appl. Environ. Microbiol.; (United States), Journal Name: Appl. Environ. Microbiol.; (United States) Vol. 43:4; ISSN AEMID
• Country of Publication: United States
• Language: English

Related Subjects

520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
BACILLUS
BACTERIA
CHALCOGENIDES
CHEMICAL REACTIONS
COMPLEXES
ELEMENTS
HYDROXY COMPOUNDS
IRON
IRON COMPOUNDS
IRON OXIDES
METALS
MICROORGANISMS
ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PRECIPITATION
SEDIMENTS
SEPARATION PROCESSES
SULFATES
SULFUR COMPOUNDS
THIOBACILLUS FERROXIDANS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS