SU947025A1 - Method for preparing astatines olutions - Google Patents

Description

(54) METHOD FOR OBTAINING ASTATE SOLUTIONS

one

The invention relates to methods for producing astatine solutions and can be used in preparative radiochemistry in the study of its chemical properties.

. A known method for producing astatatic solutions of high specific activity, according to which astatat adsorbed on a plum foil is placed in a quartz vessel evacuated to a quartz vessel with a cooled ice bottom and pro-, Q water distillates it at. In the distillation process, astatine evaporates from platinum and condenses on the cooled bottom of the vessel, from which 0.5 ml of dilute 5 nitric acid is washed out, and 30% of the astatine passes into the solution using the described method, astatum loss reaches 70%. Due to the need to use a large volume of solvent (nitric acid), solutions with a relatively low specific (volume) aotate activity are formed.

The purpose of the invention is to increase the output of astatine.

The goal is achieved by the fact that astatine adsorbed on a platinum foil is distilled at 4505 ° C, followed by its condensation into water or into aqueous solutions of alkalis, acids, salts.

PRI me R. Heat a glass tube with a length of 17Or mm, with an inner diameter of 4 mm and a wall thickness of about 1 mm and pour OD ml of water into the tube (if it is necessary to obtain an acidic or alkaline solution of astatine, acid or alkali should be poured into the tube) platinum foil with astatine adsorbed on it. In order to prevent the foil from falling to the bottom of the test tube and to prevent random particles of metal from entering the solution, it has a drop in the middle of the test tube, which halves its diameter. The hole is closed with a glass ball. The test tube is sealed with a sharp gas flame.

the burners and vertically install a metal holder in the socket of water cooled to 1 bS (to ensure good thermal contact between the wall and the holder, water is poured into the socket). The ampoule fixed in the holder is inserted into a vertical tubular electric furnace, the temperature of which increases from bottom to top from 8 ° C at the entrance to 50 ° C in the zone where the foil with astatine is located. After 4O minutes after the start of heating, 90% of astatine is distilled into water, forming a solution. The tube is withdrawn from the oven, cooled to room temperature and cut open. The lower part with the astatine solution is transferred to the laboratory for experimental studies, the upper part is removed to the radioactive waste storage. Work duration 1.5 hours

The use of the invention allows to increase the specific (volumetric) activity of astatine solutions by more than 5 times, to reduce astatine losses by more than 7 times, to reduce the labor intensity and

the duration of the solution preparation process, as well as increase the radiation safety of the work carried out. In addition, the proposed method allows, in comparison with the prototype method, to prepare astatine solutions not only in acids, but also in water, as well as in aqueous solutions of salts or alkalis.

Claims (1)

Invention Formula A method for preparing astatine solutions, including the distillation of astatine adsorbed on platinum foil at 45 ° COOOO C and its condensation, characterized in that, in order to increase the output of astatine, condensation is carried out in water OR in aqueous solutions of alkalis, acids, salts. Sources of information taken into account in the examination 1. Arrebshap, E. N. Message from the UCRb University of California UCRb - 9025, January 1960.