Premium
The Microbiological Formation of Basic Ferric Sulfates: II. Crystallization in Presence of Potassium‐, Ammonium‐, and Sodium‐Salts
Author(s) -
Ivarson K. C.,
Ross G. J.,
Miles N. M.
Publication year - 1979
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1979.03615995004300050018x
Subject(s) - jarosite , chemistry , ferrous , ferric , inorganic chemistry , potassium , sulfate , alkali metal , salt (chemistry) , ferric iron , ammonium sulfate , ammonium , crystallization , sodium sulfate , iron sulfate , sodium , nuclear chemistry , organic chemistry
Solutions of ferrous sulfate (pH 2.95) containing equivalent amounts of K + , NH 4 + , or Na + , either singly or in pairs, were inoculated with the iron‐oxidizing bacterium ( Thiobacillus ferrooxidans ) and allowed to incubate for 42 weeks. Successive quantitative analyses of the alkali cations in the single cation systems showed that after 3 to 4 weeks, virtually all of the K + in solutions had reacted to form jarosite [KFe 8 (SO 4 ) 2 (OH) 6 ]. On the other hand, after 42 weeks, about 80% of the NH 4 + and 60% of the Na + had entered into their respective basic ferric sulfates—ammoniojarosite [NH 4 Fe 3 (SO 4 ) 2 (OH) 6 ] and natrojarosite [Na Fe 3 (SO 4 ) 2 (OH) 6 ]. Progressive increases in peak intensities of the resultant X‐ray diffractograms and rates of acid production in solution agreed very well with rates of jarosite formation. In systems containing two alkali cations, solid solutions formed and the rate at which each cation disappeared from solution was similar to that in the single cation systems. The results are in accord with reported field analyses of acid sulfate soils, i.e., jarosite is the most abundant basic ferric sulfate in these soils and the soils invariably contain Fe 2+ and T. ferrooxidans .