A new approach for manufacturing and processing targets to produce 99mTc with cyclotrons

Abstract

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Molybdenum Sinter-Cladding of Solid Radioisotope Targets

“…All samples passed all of the tests successfully. The cladding remained on the substrate until a chemical dissolution was used to remove it as is done regularly in target processing [11].…”

“…Only target cladding is discussed as other stages of processing, dissolution, separation, and recovery are no different than when using other cladding techniques [11].…”

Molybdenum-100 Targets for Cyclotron Production of Technetium-99m

“…Methods proposed for large-scale target manufacturing include: electrophoretic deposition [19], pressing and sintering [11], electroplating, and carburization. Plasma spraying was investigated, but customized equipment to reduce wasteful overspray became too costly for the process to be feasible [21]. Regardless of manufacturing procedure, targets must dissipate heat during irradiation, and higher thermally conductive substrates allow higher power proton beam lines, which yield more 99m Tc.…”

“…shown that during irradiation with 6 kW, water cooling at a rate of 8 L/min will maintain the molybdenum below 260°C, which is the temperature at which any oxides inadvertently generated in situ could volatilize and contaminate the target holder and cyclotron [21]. The elliptical shape reduces the heat flux associated with high current sources because of its increased area compared with a circular target.…”

“…The elliptical shape reduces the heat flux associated with high current sources because of its increased area compared with a circular target. During irradiation, the short axis of the ellipse will be at right angles to the beam; the projection of the molybdenum target on a plane perpendicular to the beam matches the circular Gaussian beam profile [21].…”