Phosphates can form insoluble complexes of thorium phosphate with thorium and reduce the intake and translocation of thorium into the above-ground parts …

Apatite-group minerals, the dominant repository of phosphate within Earth's crust, are insoluble under most conditions 5, and the presence of Fe 2+, solubilised …

The physical and chemical properties of elemental thorium and a few representative water soluble and insoluble thorium compounds are presented in Table 3-2. Water soluble thorium compounds include the ... of the family. The salts of the alkali metals —nitrates, chlorides, sulphides, sulphates, phosphates, carbonates, etc.—are nearly all ...

Water-insoluble thorium compounds include the dioxide, dicarbonate, hydroxide, oxalate, and phosphate salts. Thorium dicarbonate is soluble …

2.1 Aqueous solubility of trialkyl phosphates, dialkylphosphites, dialkyl alkylphosphonates and alkyl dialkylphosphinates at 25 °C. The aqueous solubilities of considered compounds, treated as their concentrations in the saturated aqueous solutions, are presented in Table 1.From the most comprehensive experimental study performed at …

Environmental pollution stemming from the industrial discharge and/or storage of water-soluble thorium compounds is avoided by converting same into essentially innocuous water-insoluble thorium phosphates, notably orthorhombic thorium phosphates, by (i) reacting such water-soluble thorium compounds, e.g., the nitrates and/or chlorides, with …

The thermal evolutions of these different forms of thorium phosphates are summarized on Fig. 4. Similarly, the so-called thorium IV divanadate is the atypical end member of the M IV V 2 O 7 family ...

With anions such as fluoride, oxalate, iodate and phosphate thorium forms insoluble precipitates even in highly acidic medium, a property which is widely used for its …

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Abstract. Aqueous sulfuric acid solutions containing thorium, rare earths and phosphate cann be obtained by heating monazite with concentrated sulfuric acid, diluting the cooled reaction product with water, and separating the insoluble residue from the supernatant thoriumccntaining solution. From the latter solution the thorium is recovered by ...

Methods are described for the gravimetric determination of thorium in the presence of substantial amounts of phosphate, and of phosphate in the absence of thoria, and for the analysis of insoluble thorium phosphates. Methods are described for the gravimetric determination of thorium in the presence of substantial amounts of phosphate, and of …

The uptake of naturally occurring uranium, thorium, radium and potassium by wheat plant from two morphologically different soils of India was studied under natural field conditions. ... The other soil factors such as illite clays of alluvial soil which trap potassium in its crystal lattice and phosphates which form insoluble compounds with ...

Therefore, in this study, we analyzed the effect of thorium on Arabidopsis plants by RNA-seq profiling. Since Th and phosphorus form insoluble phosphates, we focused on the effect of Th in the presence/absence of phosphate in wild-type and mutants with altered phosphate management.

Thorium contents of the studied phosphate rock samples are 14, 10, 12, and 11 mg kg −1, and Abu Tartur phosphate rocks are characterized by their high content of rare earth elements ... (2000) Solubilization of insoluble phosphates by Aspergillus niger. Menara Perkebunan. 68(2):37–47. Google Scholar

Potassium thorium triphosphate has been prepared by thermal synthesis at 900°C. The crystal structure has been determined from three-dimensional X-ray film data (638 independent reflexions). The crystals are monoclinic (pseudoorthorhombic) with a = 8.234 (2), b = 10.187 (5), c = 10.015 (2) Å, β = 90°, but the structure was solved and ...

INSOLUBLE salts of polybasic metal ions, such as zirconium, titanium and thorium phosphates, or zirconium arsenate, tungstate and molybdate, are generally obtained as amorphous or semicrystalline materials, which undergo extensive hydrolysis even in weakly alkaline or neutral solutions31~ By refluxing amorphous zirconium phos- phate with ...

Thorium, as well as Ti and Zr, is insensitive to redox change and mainly occurs in its tetravalent form in natural environmental systems (Langmuir and Herman, 1980, Buettner and Valentine, 2012). Most Th-hosting minerals are highly resistant to weathering; hence Th has long been considered a very insoluble and immobile element …

Thorium occurs as a trace element in common rocks and rock-forming minerals, with concentrations in the range of a few pp b to a few tens of ppm ().Th 4+ has an ionic radius of ∼ 1 Å (similar to that of U 4+).This high charge and radius precludes the substitution of major ions in minerals by Th 4+.As a result, Th 4+ (and U 4+) is not accommodated in …

The rare earth phosphates are converted to insoluble sulfates, in the first case, and hydroxides in the latter. In both cases, the rare earths are subsequently dissolved away at an almost neutral pH, leaving behind thorium and uranium, together with other impurities. ... Kim and Osseo-Asare (2012) have assembled a wealth of information on …

Water-insoluble thorium compounds include the dioxide, dicarbonate, hydroxide, oxalate, and phosphate salts. Thorium dicarbonate is soluble in concentrated sodium carbonate (Weast 1983). Thorium metal and several of its compounds are commercially available.

Introduction. Thorium is primarily concentrated in highly evolved geologic systems, owing to its high charge/radius ratio, which …

By incorporating organic monomers like acrylamide, n-butyl acetate, cellulose acetate, etc. and polymers such as PAN, PS, etc. into inorganic metal …

A process for producing insoluble thorium phosphates from thorium oxalate comprising the steps of (i) repulping the thorium oxalate precipitate in water and reacting the slurry at about 60-70°C with an alkali phosphate compound to precipitate as thorium phosphate and sodium oxalate (ii) separating such thorium phosphate precipitate by filtration (iii) …

Thorium is present in seawater at only approximately 0.050 wppb, due primarily to the insoluble nature of its only oxide, ThO 2. Thus, the recovery of thorium from seawater is not a realistic option. Because 232 Th is the only isotope of natural thorium, there are no enrichment plant tails from thorium nuclear fuel.

Environmental pollution stemming from the industrial discharge and/or storage of water-soluble thorium compounds is avoided by converting same into essen tially innocuous water-insoluble thorium phosphates, notably orthorhombic thorium phosphates, by (i) react ing such water-soluble thorium compounds, e.g., the nitrates and/or chlorides, with …

Monazite mostly contains 4 wt.%â€"12 wt.% thorium (Th) and a variable amount of uranium (U), up to 14 wt.%. Xenotime, YPO4, is an yttrium phosphate mineral and frequently its Ce, La, Pr and Nd content is much less than monazite and bast- nasite.

Rock phosphate. Rock phosphate is a naturally occurring ore of marine sedimentary origin. It may have a composition of 0-30-0, but the grade is noted as 0-3-0, since rock phosphate is sparingly soluble and little of the phosphorus is available to crops. Many of the mines that produced rock phosphate are closed, and most of the marketed rock ...

Precipitation of lead phosphate also brings down quantitatively the insoluble phosphates of silver (I), cadmium (II), chromium (III), copper (II), manganese (II), thorium (IV), uranium (VI), and zirconium (IV). Detection limits for each of these are given, and thorium and uranium determinations are described in detail.

Solubility: Water: Insoluble a: Insoluble b: Very soluble b: 0.017 g/100 cc H 2 O (25°C) a Organic solvents: Soluble in HCl, H 2 SO 4, slightly soluble in HNO 3 a: Soluble in hot …