Patent Number: 041486080
Section: claims

1. A method of preparing isotope-containing samples for use in studies utilizing radioactive isotopes, said method comprising the steps of (a) combusting a sample of material containing .sup.3 H and .sup.14 C in a combustion chamber to produce combustion products containing .sup.3 H.sub.2 O and .sup.14 CO.sub.2 in gaseous form,  (b) continuously exhausting the .sup.3 H.sub.2 O and .sup.14 CO.sub.2 gas from said combustion chamber during the combustion of said material,  (c) continuously cooling the exhausted combustion products in a heat exchanger to convert the .sup.3 H.sub.2 O gas to a liquid during the combustion of said material,  (d) continuously removing said liquid from said heat exchanger during the combustion of said material and transferring said liquid to a sample collection vessel to provide a liquid sample containing the recovered .sup.3 H.sub.2 O for use in studies utilizing radioactive isotopes,  (e) maintaining the .sup.14 CO.sub.2 in gaseous form during recovery of the .sup.3 H.sub.2 O in liquid form,  (f) continuously contacting the .sup.14 CO.sub.2 with a trapping agent in a trapping chamber to convert the .sup.14 CO.sub.2 to a liquid during the combustion of said material,  (g) removing the resulting .sup.14 C-containing liquid from said trapping chamber to recover the .sup.14 C and transferring said liquid to a sample collection vessel to provide a liquid sample containing the recovered .sup.14 CO.sub.2 for use in studies utilizing radioactive isotopes,  (h) and purging said combustion chamber, heat exchanger and trapping chamber between the combustion of successive isotope-containing samples.  (a) combusting a sample of material containing .sup.14 C in a combustion chamber to produce combustion products containing .sup.14 CO.sub.2 in gaseous form,  (b) continuously exhausting said .sup.14 CO.sub.2 -containing combustion products from said combustion chamber during the combustion of said material,  (c) continuously contacting the exhausted combustion products with a trapping agent in a trapping column to convert the .sup.14 CO.sub.2 to a liquid during the combustion of said material, said trapping column comprising a series of smoothly contoured bulbous chambers each adjacent pair of which are interconnected by a smoothly contoured necked down portion with the interconnecting walls of said chambers and said necked down portions forming a smooth curvilinear configuration whereby said liquid is distributed along the length of said column in said chambers while gas is flowing therethrough and is effectively mixed with the gas flowing therethrough to effect a reaction therebetween, whereby fractional interaction between said liquid and said gas stream is effected along the length of said column,  (d) removing said liquid from said trapping column to recover the .sup.14 C and transferring said liquid to a sample collection vessel to provide a liquid sample containing the recovered isotope for use in studies utilizing radioactive isotopes,  (e) and purging said combustion chamber and trapping column between the combustion of successive isotope-containing samples. 2. A method of preparing samples as set forth in claim 1 wherein said combustion chamber is flushed with a fluid subsequent to the combustion step so as to sweep any residual combustion products out of said chamber and on through said heat exchanger and said trapping chamber to achieve substantially complete recovery of the .sup.3 H.sub.2 O and substantially complete trapping of the .sup.14 CO.sub.2 while purging the system prior to combustion of the next sample, and flushing said trapping chamber with a fluid subsequent to the removal of the .sup.14 C-containing liquid therefrom to achieve substantially complete recovery of the .sup.14 C while purging the trapping chamber prior to combustion of the next sample. 3. A method as set forth in claim 1 wherein said trapping chamber comprises a series of smoothly contoured bulbous chambers each adjacent pair of which are interconnected by a smoothly contoured necked down portion with the interconnecting walls of said bulbous chambers and said necked down portions forming a smooth curvilinear configuration whereby said liquid is distributed along the length of said column in said bulbous chambers while gas is flowing therethrough and is effectively mixed with the gas flowing therethrough to effect a reaction therebetween, whereby fractional interaction between said liquid and said gas stream is effected along the length of said trapping chamber. 4. A method of preparing isotope-containing samples for use in studies utilizing radioactive isotopes, said method comprising 5. A method of preparing samples as set forth in claim 4 wherein said exhausting and contacting steps are continued after completion of the combustion of the sample material until substantially all the .sup.14 CO.sub.2 is recovered from the combustion chamber. 6. A method of preparing samples as set forth in claim 4 wherein said combustion chamber is flushed with a fluid subsequent to the combustion step so as to sweep any residual combustion products out of said chamber and on through said trapping column to achieve substantially complete trapping of the .sup.14 CO.sub.2 while purging the system prior to combustion of the next sample, the flushing said trapping column with a fluid subsequent to the removal of the .sup.14 C-containing liquid therefrom to achieve substantially complete recovery of the .sup.14 C while purging the trapping column prior to combustion of the next sample. 7. A method of preparing samples as set forth in claim 6 wherein the flushing fluid for removing the liquid from said trapping column is an inert gas. 8. A method of preparing samples as set forth in claim 4 which includes the step of supplying oxygen to said combustion chamber at a controlled rate during the combustion of said material.