Method of regeneration of platinum contaminated with uranium and/or plutonium, americium

 

(57) Abstract:

The invention relates to the field of recycling of metal waste. The inventive method of regeneration of platinum contaminated with uranium and/or plutonium, americium, is that the processing of platinum carried out by a mixture of nitric and hydrochloric acids. The resulting solution before deposition of platinum adjust the acidity in the range of 0.5-3.0 g-ecvn+/l and purified from radionuclides by contacting with solid extractant based phosphine oxide raznorabochego. Advantages of the invention are to increase the efficiency of the treatment method. 1 PL.

The invention relates to a process for the regeneration of platinum contaminated with uranium and/or plutonium, americium, product, suitable for secondary raw materials.

Known methods of decontamination of metals and alloys in solutions of mineral acids with the addition of complexing agents and surfactants /N. And. Anpilogov and other Decontamination in nuclear engineering. M, Energoizdat, 1982, S. 120-131/.

However, the deep diffusion of radionuclides inside material the use of these methods for decontamination of platinum uneconomical because of vozrasta the/P>

The method for extracting platinum group metals from radioactive solutions containing nitric acid (see Japan patent No. 4160177, publ. 03.06.1992, class 25 With 1/20). This solution is chosen as the prototype.

From the contaminated solution extract platinum group metals by electrolytic method. Solution adjust the concentration of nitric acid and add the hydrogen peroxide.

This method is costly and unsafe.

The objective of the invention is to develop a method that ensures the regeneration of platinum contaminated with uranium and/or plutonium, americium, to obtain secondary raw materials.

The problem is solved in that in the method of regeneration of platinum contaminated with uranium and/or plutonium, americium, including the processing of its acid solution and the deposition of platinum from a solution, the platinum processing carried out by a mixture of nitric and hydrochloric acids. The resulting solution containing platinum and radionuclides, before deposition adjust the acidity in the range of 0.5-3.0 g-ecvn+/l and purified from radionuclides by contacting with solid extractant based phosphine oxide raznorabochego (tax HUF).

min was subjected to etching with a solution containing 4 mol/l nitric and 2 mol/l hydrochloric acid. Etching conducted in several sessions of 15 minutes of boiling, changing the solution to the complete decontamination of scrap. Received from etching solutions were combined.

After 6 times of processing of the received 82.3 g of pure scrap and 1.5 l of a solution with a concentration of platinum of 20.3 g/l and hydrogen ions 4.7 g-EQ/l To determine the effect of pH solution on the depth of clearing it from radionuclides portions of a solution of 50 ml containing 1,02 g of platinum, was treated with caustic soda, reducing the acidity in each portion from the source to the target value in the range of 4.7-0.2 g-ecvn+/L. the thus Prepared solution was passed through a column loaded with them tax HUF in the amount of 10 ml and the layer height 80 mm, the Solution was passed at a rate of 0.5 Nr. about/hours

From purified thus solutions besieged platinum in the form of the “mob” by well-known methods /C. F. Hillebrand and other Practical guide to inorganic analysis./Ed. by Y. Y. Lurie. M., 1960, S. 392-393/. The solution was evaporated with hydrochloric acid to destroy nitrates, was diluted with water to 100 ml, was added formic acid and sodium acetate at a rate of 1 ml lnai coagulation sludge platinum and clarification of the solution. Precipitate of platinum was separated from the solution by filtration on filter paper, washed with hot 1% solution of ammonium chloride and progulivali in a muffle furnace at 600° C for 1 h the resulting powder platinum “mobile” measured on the surface radiometer SPAR. The results are presented in the table.

The table shows that the optimal interval acidity cleaned from radionuclide solution is in the range of 0.5-3.0 g-ecvn+/l (op.2-4, 8). The remainder of the solution (op.8) was purified from the radionuclides as specified in acidity 1.6 g-ecvn+/l In experiments 2-4, 8 precipitated from a solution of platinum “mob” clean corresponded to the level allowed for use as secondary raw materials.

Thus, the method provides regeneration of platinum at its decontamination from uranium and/or plutonium, americium obtaining secondary raw materials to 98,0% by weight of decontaminated scrap.

Method of regeneration of platinum contaminated with uranium and/or plutonium, americium, including the processing of its acid solution and the deposition of platinum from a solution, characterized in that the processing of platinum carried out by a mixture of nitric and hydrochloric acid, the resulting solution, containing the P>/l and purified from radionuclides by contacting with solid extractant based phosphine oxide raznorabochego.



 

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