Other Binders - Stabilization and Solidification of Hazardous, Radioactive, and Mixed Wastes - page 106

TABLE 6.1.2 (CONTINUED)
Selected Treatment Studies for Heavy Metals and Radionuclides Using
Phosphates; Includes Laboratory Studies, Field Trials, and Applications

Metal/
Metalloid
Studied

Media/
Conditions

Phosphate
Treatment

Mechanism/Solid
Phases Formed References

U, Sr Synthetic acidic

uranium mill
effluent

Synthetic
hydroxyapatite

Sorption and
coprecipitation

72

U 0.1 M KNO 3

aqueous solution

Synthetic
hydroxy-
apatite, cattle
bone
hydroxyapatite
prepared at
500, 700, 900,
and 1100°C

Not determined 73

U Aqueous solution Natural

fluorapatite

Not determined 74

U Aqueous solution Synthetic

hydroxyapatite

At U sorbed < 4700 ppm
formed as inner-sphere
complex; at U sorbed >
7000 ppm formation of
chernikovite

75

U Aqueous solution,

solids

Bone charcoal
and bonemeal

Surface complex for U
sorbed < 5500 ug U(VI)/g
and at U sorbed > 5500 ug
U(VI)/g chernikovite
formation

76

U Aqueous solution Synthetic

fluorapatite

Substitution of U(VI) for
Ca

77

U, Ce Soil Synthetic

hydroxyapatite

Not determined 47b

U, Pb Aqueous solution;

synthetic
groundwater

Apatite II™ —
commercial
apatite mineral
product
derived from
fish bones

For uranium formation of
autunite; not determined
for Ce

78

U, Pb, Pu Aqueous solution Apatite II —

commercial
apatite mineral
product
derived from
fish bones

Formation of U and Pb
phosphates

79

(continued)