SU1402881A1 - Method of determining isotopic composition of copper - Google Patents

Description

The invention relates to analytical chemistry, in particular to the quantitative determination of the isotopic composition of copper, allows determining the isotopic composition of metallic copper, copper B of its compounds, including in natural objects, and can find practical application in geochemistry, analytical chemistry, as well as a method of control in obtaining enriched and pure copper isotopes.

The aim of the invention is to increase the accuracy and speed, as well as simplify the method.

Fig. 1 shows the spectrum of a toluene solution of bis (diethyldithiocarbamate) copper (II) (natural isotopes), a general view; in Figure 2 the high-field components of the EPR spectrum of bis- (diethyldithiocarbamate) copper (II) and the determination of intensities I component of the spectrum; in fig. 3 is a calibration graph — the dependence of copper isotopic composition on the intensity ratio of component I of the EPR spectrum, where

with,

6 5

is the intensity of the EPR spectrum component due to the Cu isotope.

The calibration plot is constructed as follows.

Starting from copper salt with the natural content of isotopes and from pure copper isotopic salts, copper (II) bis bis (dithyldithiocarbamates) are obtained, differing in isotopic content. Then the solutions are degassed and their EPR spectra are recorded (Fig. 1). For each combination of isotopes, the ratio of the amplitudes of the components of the JTS, which are associated with each of the isotopes, is calculated (Fig. 1). Based on the data obtained, a calibration graph of the dependence of (-I-Cu) on the isotope content (Fig. 3) is constructed, the error in constructing the calibration schedule and the preparation of reference solutions may be due to the fact that in enriched copper isotopes the content of the main component (according to passport specifications) is given with an error of + 0.1% (absolute).

Example 1.B20 cm of water grow 10 mg of copper acetate acetate monohydrate Cu (CH-, COO) 2 H20 (pure isotope Cu)

O

five

0 5

five

0

five

0

five

and 23.2 mg Cu (CH3COO), (with natural content of isotopes). To the resulting solution was added 3 cm of the TETDS toluene solution (C LY mol / L). B For 6 min, the solutions were shaken. A toluene solution (0.6 cm) of the resulting bis- (diethyldithiocarbamate) copper (II) (isotopic composition: Cu 90.7%; Cu 9.3%) was degassed for 12 min at a residual pressure of 0.5 ° 10 mm Hg and recorded the EPR spectrum 6 times. Spectra were used to measure the amplitudes of the HFS components from copper isotopes, and the ratios 1.th / 1ccb were calculated. They correlated the obtained values with the calibration schedule and found how many of that and another isotope in the sample. The analysis (along with preliminary preparation) took 70 minutes.

Example 2. A portion of chalcopyrite (natural content of isotopes) 500 mg was filled into a test tube with 5 cm of dry tea TETDS (C 1-10 mol / l). Contents were shaken for 4 minutes. The solution was degassed for 8 min at a residual pressure of 1 Hg, and the EPR spectrum was recorded 6 times. The spectra measured the amplitudes of the HFS components from copper isotopes and calculated the ratios - Cu. The values obtained with the calibration graph found the isotope content. The analysis time is 1 hour.

Claims (1)

Invention Formula The method of determining the isotopic composition of copper, including sampling and sample preparation, spectrum registration and calculation of the isotopic composition spectrum, characterized in that, in order to improve the accuracy, speed and simplicity of the method, the sample preparation is carried out with shaking at room temperature in contact with the thermal system. with a solution with a concentration of 10 mol / l of tetraethylthiuram disulfide, the resulting solution is degassed with the sample being analyzed, the EPR spectrum is recorded, and the isotopic composition is calculated from the amplitudes of the components and ESR caused by copper ions isotopes C and C, using the calibration curve. 2 | J g roO% Cu mY Cf /