What Ä°s Thorium?
12 Temmuz 2007
What is Thorium?
Thorium is a naturally-occurring, slightly radioactive metal discovered in 1828 by the Swedish chemict Jons Jacob Berzelius, who named it after Thor, the Norse god of war.It is found in small amounts in most rocks and soils, where it is about three times more abundant than uranium.Soil commonly contains an average of around 6 parts per million of thorium.
Thorium, as well as uranium, can be used as a nuclear fuel. Although not fissile itself, thorium-232 will absorb slow neutrons to produce uranium-233, which is fissile. Hence like uranium-238 it is fertile.
Domestic Production and use:
The primary source of the worldÂ’s thorium is the rare-earth and thorium phosphate mineral, monazite.Monazite was not recovered as a salable product during domestic processing of heavy mineral sands in 2001. Past production had been as a byproduct during processing for titanium and zirconium minerals, and monazite wasrecovered for its rare-earth content. Essentially all thorium compounds and alloys consumed by the domestic industry were derived from imports, stocks of previously imported materials. About eigth companies processed or fabricated various forms of thorium for nonenergy uses, such as high-temperature ceramics, catalyts, and welding electrodes. The value of thorium metal, alloys, and compounds used by the domestic industry was estimated to be about $100,000.
World Refinery Production, Reserves, and Reserve Base:
Reserves and reserve base are contained primarily in the rare-earth ore mineral, monazite. Without demand for the rare earth, monazite would probably not be recovered for its thorium content. Other ore minerals with higher thorium contents, such as thorite, would be more likely sources if demand significantly increased. No new demand, however, is expected. Reserves exist primarily in recent and ancient placer deposits. Lesser quantities of thorium-bearing monazite reserves occur in vein deposits and carbonatites.
Refinery production
2000 2001
Reserves
Reserve Base
Australia
—- —-
300,000
340,000
Brazil
NA NA
16,000
18,000
Canada
NA NA
100,000
100,000
India
NA NA
290,000
300,000
Malaysia
—- —-
4,500
4,500
Norway
—- —-
170,000
180,000
South Africa
—- —-
35,000
39,000
United States
—- —-
160,000
300,000
Other countries
NA NA
90,000
100,000
World total
NA NA
1,200,000
1,400,000
Domestic mine production of thorium-bearing monazite ceased at the end of 1994 as world demand for ores containing naturally occurring radioactive thorium declined. Imports and existing stocks supplied essentially all thorium consumed in the United States in 2001. Domestic demand for thorium ores, compounds, metals, and alloys has exhibited a long-term declining trend. Thorium consumption in the United States decreased in 2000 to 2.0 tons; however, most material was consumed in a nonrecurring application. In 2001, thorium consumption, primarily for use in catalyst applications, is estimated to decrease. On the basis of data through August 2001, the average value of imported thorium compounds decreaes to $36.58 per kilogram from the 2000 average of $47.76 per kilogram (gross weight).
Year Price
Year Price
Year Price
Year Price
1959 43.10
1960 43.10
1961 43.10
1962 33.07
1963 44.09
1964 33.07
1965 33.07
1966 33.07
1967 33.07
1968 33.07
1969 33.07
1970 33.07
1971 33.07
1972 33.07
1973 33.07
1974 33.07
1975 33.07
1976 33.07
1977 33.07
1978 33.07
1979 33.07
1980 NA
1981 NA
1982 NA
1983 NA
1984 NA
1985 NA
1986 NA
1987 NA
1988 NA
1989 NA
1990 NA
1991 NA
1992 NA
1993 NA
1994 NA
1995 NA
1996 NA
1997 NA
1998 NA
NA:Not Available
In Turkey:
(TON)
Average
Tenor(U O )
Reserves
(%)
Manisa-Salihli
Köprübaşı
2852
0.04-0.05
Uşak-Fakılı
490
0.05
Aydın-Küçükçavdar
208
0.04
Aydın-Demirtepe
1729
0.08
Yozgat-Sorgun
3850
0.1
Total Uranium Reserves
9129
Total Thorium Reserves
380000
Kategori: Bilim