Polonium phosphate

Solvent extraction by tributyl phosphate (TBP) (13, 96), dithizone (20, 71, 72), cupferron (89), thenoyl trifluoroacetone (TTA) (55), diiso-propyl ketone (26), mesityl oxide (92), tri-n-benzylamine and methyl di-n-octylamine (99), diisopropyl and diisobutyl carbinol (100) have all found some application on the trace scale. Acetylaeetone and methyl isobutyl ketone extract milligram amounts of polonium almost quantitatively from hydrochloric acid, but the stable polonium-organic compounds which are formed make it difficult to recover the polonium in a useful form from solutions in these ketones (7). Ion exchange (22, 115, 119) and paper chromatography (44, 87) have also been used for trace scale separations of polonium, but the effects of the intense alpha-radiation on organic com-... 

Complexes with organic compounds have been reported. Solubility studies with tributyl phosphate (TBP) indicate the formation of a complex PoC14-2TBP (IS). Weighable amounts of polonium tetrachloride in dilute hydrochloric acid can be titrated to a colorless end point with ethylene-diamine tetra-acetic acid (EDTA) the results suggest a complex with two molecules of EDTA, but solubility studies favor a 1 1 complex. The EDTA complex is soluble in alkali and is more stable in alkaline than in acid media, but the ligand is rapidly destroyed by the radiation and solvent radiolysis products 12). However, EDTA can apparently be used to complex trace polonium in the separation of radium D-E-F mixtures (129). 

This is a white, gelatinous solid of composition close to 2Po02-H3P04, made by the action of 1 M diammouium phosphate on solid polonium tetrachloride or of 2 M phosphoric acid on polonium hydroxide. It appears... 

Although tellurium tetrachloride has been reported55 to form a 1 2 complex with acetamide, there appears to be little other information available on the complex. Similarly, the reported tributyl phosphate complex of polonium tetrachloride56 has received little attention. The formation of a polonium(IV) perchlorate complex with tributyl phosphate has been suggested57 in the solvent extraction of polonium from perchloric acid. 

Uranium is another example of a contaminant often found in phosphate fertilizers. Also, highly radioactive Polonium-210 contained in phosphate fertilizers is absorbed by the roots of plants and stored in its tissues tobacco derived from plants fertilized by rock phosphates contains Polonium-210 which emits alpha radiation estimated to cause lung cancer. 

A convenient iriethod for removing polonium from bismuth or lead has been patented by Karraker (Kl). The polonium Is removed from dilute hydrochloric acid solution by extraction with tr lbutyl phosphate ether or by a 20% sdlutlon of tributyl phosphate In dibutyl ether (H9).. ... 

The need to exclude low levels of natural radionuclides from unnecessary legislation was recognised at an early stage in the UK. The Radioactive Substances Act (RSA, 1993) defined eight radioelements, all within the natural uranium and thorium decay chains, that constituted radioactive material only if present above a certain threshold. Problems arose with anthropogenic radionuclides, not considered above, and owing to various, established practices that required a large number of bespoke and somewhat ad hoc exemption orders the most important of which in the current context was the Phosphatic Substances and Rare Earths etc. Exemption Order (PSRE). The need for elemental activity concentrations meant that, polonium for example was calculated from ... 

In some instances, the source of radon is in wastes from uranium mining or phosphate production. In most cases, it is emitted by the radioactive decay of present in small amounts in rocks and soils. Because radon is a gas, it readily passes through air passages in the body and is breathed in and out. The product formed when a Rn atom gives up an a particle is the isotope polonium-218, which also emits a particles. Unlike radon, polonium is a solid. Health hazards posed by radon seem to be from Po and other radioactive decay products becoming attached to dust particles in the air and then being breathed into the lungs. 

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