Patent Number: 043839690
Section: claims

1. Method for the removal of the small amounts of carbon monoxide, carbon dioxide and gaseous alkanes in which the compounds have radioactive carbons, produced in nuclear power stations and contained in the exhaust gases of the purification plant, which comprises subjecting exhaust gases containing the mixture of carbon monoxide, carbon dioxide and gaseous alkanes in which the compounds have radioactive carbons, to oxidation to effect substantially complete conversion of the mixture of the radioactive compounds to radioactive carbon dioxide, and subsequently removing substantially all said radioactive carbon dioxide from the exhaust gases containing it. 2. Method according to claim 1, wherein said oxidation is obtained by passing said exhaust gas with a slight amount of excess oxygen in contact with palladium contact bodies at a temperature of .gtoreq.450.degree. C. 3. Method according to claim 1, wherein said oxidation is obtained by passing said exhaust gas with a slight amount of excess oxygen in contact with platinum contact bodies at a temperature of about 500.degree. C. 4. Method according to claim 1, wherein said oxidation is obtained by passing said exhaust gas with a slight amount of excess oxygen in contact with CuO contact bodies at a temperature at least about 750.degree. C. 5. Method according to claim 1, wherein said exhaust gas after oxidation is subjected to cooling and said cooled exhaust gas subsequently passed in contact with an absorption medium to effect removal of the .sup.14 CO.sub.2. 6. Method according to claim 5, wherein said absorption medium is a sodium or potassium hydroxide solution with a small amount of BaCl.sub.2. 7. Method according to claim 5, wherein said absorption medium is a Ba(OH).sub.2 solution in which Ba.sup.14 CO.sub.3 precipitates. 8. Method according to claim 5, wherein said absorption medium is a solid alkaline absorbent material such as soda lime and sodium asbestos. 9. Method according to claim 1, wherein a non-radioactive carbon containing carrier gas is admixed with said exhaust gases. 10. Method according to claim 9, wherein the said carrier gas is methane. 11. Method according to claim 10, wherein said carrier gas is about 0.1% by volume of the exhaust gases.