Uranium immobilization by sulfate-reducing biofilms grown on hematite, dolomite, and calcite.
Biofilms of sulfate-reducing bacteria Desulfovibrio desulfuricans G20 were used to reduce dissolved U(VI) and subsequently immobilize U(IV) in the presence of uranium-complexing carbonates. The biofilms were grown in three identically operated fixed bed reactors, filled with three types of minerals: one noncarbonate-bearing mineral (hematite) and two carbonate-bearing minerals (calcite and dolomite). The source of carbonates in the reactors filled with calcite and dolomite were the minerals, while in the reactor filled with hematite it was a 10 mM carbonate buffer, pH 7.2, which we added to the growth medium. Our five-month study demonstrated that the sulfate-reducing biofilms grown in all reactors were able to immobilize/reduce uranium efficiently, despite the presence of uranium-complexing carbonates.
Marsili
Enrico
E
Center for Biofilm Engineering, Department of Civil Engineering, Montana State University, Bozeman, Montana 59717, USA.
Beyenal
Haluk
H
Di Palma
Luca
L
Merli
Carlo
C
Dohnalkova
Alice
A
Amonette
James E
JE
Lewandowski
Zbigniew
Z
D018441:Biofilms; D002119:Calcium Carbonate / Q000737:chemistry*; D045285:Desulfovibrio desulfuricans / Q000378:metabolism*; D005290:Ferric Compounds / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*; D014501:Uranium / Q000378:metabolism*
D005290:Ferric Compounds; D013431:Sulfates; C000499:ferric oxide; D014501:Uranium; D002119:Calcium Carbonate; D008274:Magnesium; C028042:calcium magnesium carbonate