Cyclotron targets

Other elements often separated from pile or cyclotron targets by distillation or volatilisation are tritium (3), germanium as the bromide (23), arsenic as the trichloride (67), technetium (23), (91), rhenium (24), (25) and osmium (25) as oxides. 

Carrier-free Radioisotopes from Cyclotron Targets. XI. Preparation... 

Radioisotopes from Cyclotron Targets. XVI. Preparation and Isolation of Pd103 from Rhodium. J. chem. Physics 19, 660 (1951)-... 

Carrier-free Radioisotopes from Cyclotron Targets. VI. Preparation and isolation of 10s.108.UIAg from Palladium. J. chem. Physics 18, 391 (1950). 

Molecular [ F]fluorine (P F]F2) is produced in the cyclotron target usually during the irradiation for radioisotope production (see Section 2.4). 

The preparation of reactive F-18 has recently been reviewed (4). Labeled molecular fluorine was first prepared from the Ne (d, alpha)i F reaction by bombarding Ne-20 containing a trace of F2 with a deuteron beam in an all-nickel cyclotron target (12.). Approximately one third of the radioisotope is exchanged into the desired chemical form, the rest being either bound to the nickel... 

Separatlbns from bismuth are Important for many radiochemical applications. If macro amounts of either constituent Is present as In the use of a lead or bismuth cyclotron target, a preliminary separation as by precipitation of lead sulfate or bismuth oxychloride may be necessary. The extraction coefficients for lead, bismuth and thallium over the. pH range of Interest- for their separation are summarized In Figure 19. Bismuth can be separated by extracting It from a buffered solution at pH 2.6... 

If a nickel foil or nickel powder is stirred In a dilute (0.5 M) solution of HaD(Pb °), RaE(Bl °) and RaF(Po °)-the bismuth and polonlxom will deposit on the nickel leaving the lead-210 In solution (R5). This has been used for separation of bismuth Isotopes from lead cyclotron targets (M18). Gold, mercury, platinum, copper, silver, palladium and antimony also deposit. 

Separation of carrier-free lead samples from inert or radioactive contaminants present in macro or tracer quantities can be accomplished by any of a number of the waiys that have been outlined in the foregoing sections on techniques. Ion exchange (k8), solvent extraction (R7), and "filter paper chromatography (P10)(P11) have all been used for separation of carrier-free radioisotopes. A precipitation separation of carrier-free lead from thallium oxide cyclotron targets has alsq been proposed (06) (W8). In this procedure, the target material is dissolved In nitric acid, sulfurous acid is introduced to reduce the thallium to the univalent state, the lead is carried on a Iron-III hydroxide precipitate by addition of iron carrier and ammonium hydroxide. After dissolution of the hydroxide in hydrochloric acid. Iron was extracted Into ethyl ether leaving the carrier-free lead in aqueous solution. 

Lead metal is easily dissolved in nitric acid. Lead dioxide which is occasionally used for cyclotron targets or is sometimes produced during separations by anodic oxidation can be dissolved in nitric acid by dropwlse addition of hydrogen peroxide. 

C. Separation of lead from cyclotron targets and complex mixtures. 

Procedure No. 10. Separation of. lead from thallium cyclotron. targets.Karraker. 

Separation of lead from thallium cyclotron targets. Procedure 82-1 from W. Meinke "Chemical Procedures Used In Bombardment Work at Berkeley", UCRL-432 (August 30, 1949) Procedure by Karrakerj Target Material thallium Type of bbdt 60-8o Mev or K " Time for sepn. -, 1 hour Yield 955 Degree of purification good, at least factor of 100 Advantages one step Is usually sufficient purification.. 

R- D. Maxwellf H. R, Haymondj D. R. Bomberger, W. M. Garrison, and J. G. Hamilton "Carrier-Free Radioisotopes from Cyclotron Targets. 

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