Zirconium carbonates

Chelated complexes such as sodium zirconium lactate [15529-67-6] or ammonium zirconium carbonate [22829-17-0] and acidic forms such as zirconium hydroxy oxide chloride [18428-88-1] have been used in preparations in deodorants or for treatment for poison oak and poison ivy dermatitis. In such occasions, when the skin had been cut or abraded, a few users developed granulomas which have been identified as a delayed hypersensitivity to zirconium (99). These may take several weeks to develop, and commonly persist for 6 months to over a year. 

Oxide Chlorides. Zirconium oxide dichloride, ZrOCl2 -8H2 0 [13520-92-8] commonly called zirconium oxychloride, is really a hydroxyl chloride, [Zr4(OH)g T6H2 0]Clg T2H2O (189). Zirconium oxychloride is produced commercially by caustic fusion of zircon, followed by water washing to remove sodium siUcate and to hydrolyze the sodium zirconate the wet filter pulp is dissolved in hot hydrochloric acid, and ZrOCl2 -8H2 O is recovered from the solution by crystallization. An aqueous solution is also produced by the dissolution and hydrolysis of zirconium tetrachloride in water, or by the addition of hydrochloric acid to zirconium carbonate. 

Carbonates. Basic zirconium carbonate [37356-18-6] is produced in a two-step process in which zirconium is precipitated as a basic sulfate from an oxychloride solution. The carbonate is formed by an exchange reaction between a water slurry of basic zirconium sulfate and sodium carbonate or ammonium carbonate at 80°C (203). The particulate product is easily filtered. Freshly precipitated zirconium hydroxide, dispersed in water under carbon dioxide in a pressure vessel at ca 200—300 kPa (2—3 atm), absorbs carbon dioxide to form the basic zirconium carbonate (204). Washed free of other anions, it can be dissolved in organic acids such as lactic, acetic, citric, oxaUc, and tartaric to form zirconium oxy salts of these acids. 

Basic zirconium carbonate is nominally 2Zr02 -C02 -2 112 0 but the Zr02 C02 ratio may range from 4 1 to 1 1 depending on the methods and techniques of preparation. 

Basic zirconium carbonate reacts with sodium or ammonium carbonate solutions to give water-soluble double carbonates. The ammonium double carbonate is nominally NH4[Zr20(0H)2(C02)3]. These solutions are stable at room temperature, but upon heating they lose carbon dioxide and hydrous zirconia precipitates. 

The most common basic sulfate is 5Zr02 ASO 535. [84583-91-5] which is precipitated in good yield when a zirconium oxychloride solution is heated with the stoichiometric amount in sulfate ion. It is used to prepare high purity oxides and ammonium zirconium carbonate. 

Potassium trisiamylborohydride, 20 605 Potassium winchite, 3 289 Potassium-zirconium carbonate, 26 637 Potato branching enzyme, 12 493 Potatoes, citric acid in, 6 632t Potato fungicide, 13 57 Potato starch, 4 724t Potential energy diagrams, 10 118-119 Potential gum test, 12 400 Potentiated toxic effects, 25 214 Potentiometric measurements, 14 612 Potentiometric titrations, 9 585-58 ... 

Barium, Halocarbons, 0200 Beryllium, Halocarbons, 0220 f Bromomethane, Metals, 0429 Chloroform, Metals, 0372 Plutonium, Carbon tetrachloride, 4888 Samarium, 1,1,2-Trichlorotrifluoroethane, 4911 Tin, Carbon tetrachloride, Water, 4912 Titanium, Halocarbons, 4919 Uranium, Carbon tetrachloride, 4923 Zirconium, Carbon tetrachloride, 4928 See also HALOCARBONS METALS... 

A. Fernandez Guillermet, Analysis of thermochemical properties and phase stability in the zirconium-carbon system, Journal of Alloys and Compounds, 217 (1995) 69-89. 

As mentioned, zircon (ZrSiO ) has many forms, but the most used is the transparent crystal that is cut to resemble a diamond. There is even one form of zirconium used in medicine zirconium carbonate (dZrO COj HjO), which, as a lotion, can be used to treat poison ivy infections. 

Zirconium carbonate (dZrO COj HjO), when used as an additive to lotion, is an effective treatment for skin exposed to poison ivy. 

Also, the oxide may be prepared in the laboratory by thermal decomposition of zirconium hydroxide or zirconium carbonate ... 

Aluminium drinking carts. There are many patents [8] referring to the use of fluorozirconic acid (H2ZrF6)-based systems to treat the surface of aluminium cans to improve the corrosion resistance of the metal and the adhesion of the applied coatings. Typically, the zirconium fluoride will be used in conjunction with polyacrylic acid, presumably to form a complex in situ which acts as an adhesion promoter. Such surface treatment of aluminium is not restricted to zirconium fluorides, as ammonium zirconium carbonate displays similar properties in such application areas. 

A recent patent by Thomason [15] has revealed that ammonium zirconium carbonate when applied to a substrate such as glass, aluminium, or polypropylene can improve the adhesion of microsphere polymer-based adhesives. It is proposed that the zirconium after reacting with the substrate surface reacts with carboxyl groups at the surface of the polymer microspheres. 

Cyclohexylisonitrile inserts selectively into the endocyclic vinyltitanium bond of a-methylenetitanacyclobutene complexes 37, although the reaction fails for many other isonitriles (Equation 12) <19960M1176>. No insertion occurs upon treatment with nitriles or ketones, in contrast to the established reactivity of typical titanacyclobutenes <1996CHEC-II(lb)887>. The reaction of fert-butylisonitrile with 1,9-anthracenediyl-zirconocene complex 38 proceeds exclusively by insertion into the terminal ring zirconium-carbon bond, presumably due to steric considerations (Equation 13) <2000JA9880>. 

In recent years, amines have also been synthesized by nitrogen insertion into a zirconium-carbon bond followed by hydrogenolysis [75] (Scheme 28). 

Sulfur and selenium heterocycles have also been prepared by reaction of zirconium-benzyne complexes with the elemental chalcogens. In these reactions, chalcogens insert into both of the zirconium-carbon bonds (Scheme 7).53-55 Interestingly, neither para-bromo norpara-dimethylamino substituents in 65 interfere with their conversion to 66 (60-80% yields).54 Complexes 66 react further with mono- and bifunctionalized electrophiles (Scheme 7) to yield ort/io-dichalcogenated benzenic compounds 67-69. 

The aqueous chemistry of zirconium is complex and dominated by hydrolysis. One aspect is that polymerization takes place when salt solutions are diluted. The polymeric species can be cationic, anionic, or neutral. Polymers that are formed include ammonium zirconium carbonate, zirconium acetate, and zirconium oxychloride. 

Ammonium carbonate solution white precipitate of basic zirconium carbonate, readily soluble in excess of the reagent, but reprecipitated on boiling. 

The reactivity of a silyl-zirconium complex is interesting because an unsaturated bond would be inserted into the silyl-zirconium bond to provide an alternative zirconium complex. It has zirconium-carbon and silyl-carbon... 

To examine the reactivity of the silyl-zirconium bond, Mori et al. used Me2PhSiLi instead of Ph2tBuSiLi. A THF solution of Me2PhSiLi 8b (1 equiv.) was added to a THF solution of Cp2ZrCl2 (1 equiv.) and diphenylacetylene 14a (1 equiv.) at -78 °C, and the solution was stirred at room temperature for 3 h. After hydrolysis of the reaction mixture, vinylsilane 15a was obtained in 36% yield along with the starting material 14a in 40% yield. When the reaction mixture was treated with D20, compound 15a-D2 having two deuteriums was obtained. One deuterium was introduced at the vinylic position and the other was incorporated into the methyl proton on the silicon (39% yield, each D content quant.). If insertion of alkyne 14a into the zirconium-carbon bond of lb occurs, vinylsilane 15a should be formed, but in this case only one deu-... 

The possible reaction mechanism for the formation of 31 is shown in Scheme 15. Insertion of alkyne 14 into silazirconacyclopropane 3 gives silazirconacyclopentene 22. Then, insertion of carbon monoxide into the carbon-zirconium bond in silazirconacyclopentene 22 gives silazirconacyclohexenone 34, whose carbonyl oxygen would coordinate to zirconium metal. Then the zirconium carbon bond migrates onto silicon to afford oxazirconacyclohexene 36 via 35 [26]. Deuterolysis of 36 would afford 31-D2, which has two deuteriums. 

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