Acids zirconium

Zirconium carbide is inert to most reagents but is dissolved by hydrofluoric acid solutions which also contain nitrate or peroxide ions, and by hot concentrated sulfuric acid. Zirconium carbide reacts exothermically with halogens above 250°C to form zirconium tetrahaHdes, and with oxidizers to zirconium dioxide in ak above 700°C. Zirconium carbide forms soHd solutions with other transition-metal carbides and most of the transition-metal... 

Zirconium lias outstanding resistance to hydrochloric acid and is a cheaper alternative to titanium for this duty. It is superior to titanium in resistance to sulfuric acid. Zirconium has excellent resistance to caustic alkalies in all concentrations and is superior to both titanium and tantalum in this respect. 

An example of the modular preparation of the cyclophane 3 from the substituted bipyridine 2 and a general tripeptide 1 is shown in Scheme 3-3. The host molecule 3 contains a pre-organized binding pocket. The overall basicity of such molecules also facilitates their intercalation within the lamellas of acidic zirconium phosphate, thus making this chemistry well suited for the desired application. 

Preparation and characterization of two-dimensional zirconium phosphonate derivatives in either crystalline or amorphous forms have been investigated. Two composite zirconium phosphonates in single crystal phase have also been investigated and characterized by XRD, i c-, and 3ip-MASNMR. The catalytic performance over zirconium phosphonates are evaluated by hydrolysis of ethylacetate in aqueous solution. When the composite zirconium phosphonate is composed with an acidic function and with a hydrophobic function in single crystal phase, the catalytic activity in aqueous medium showed higher activity than that of single acidic zirconium phosphonate. The composite materials become accessible to any reactant molecule and improve hydnq>hobicity. 

The acidic function of single zirconium phosphonate showed rather poor catalytic activities for hydrolysis of ethylacetate in aqueous solutions. In addition, over Zr(03PCH2S03H)2 catalyst, the reaction proceeds as a homogeneous reaction, even though the catalytic activity is higher than other acidic zirconium phosphonates. The objective of this study is to explore the role of a second phosphonate function in single crystal phase on the catalytic performance of acidic function and hydrophobic function of zirconium phosphonates and to learn how to exploit this second function to achieve a catalytic advantage in certain applications. 

Cation exchange, solvent extraction and Raman spectroscopic studies of highly acidic zirconium sulfate solutions suggest that these solutions contain a mixture of solution species having from one to four sulfate ligands per Zr atom.153,351 The sulfato-zirconium complexes appear to be somewhat more stable than the analogous hafnium complexes.351... 

Zirconium Arsenates.—Zirconium Orthoarsenate, Zr3(As04)4. 5H20, has been obtained 5 as a voluminous white precipitate by adding sodium monohydrogen orthoarsenate to a solution of zireonyl fluoride in hydrochloric acid. Zirconium monohydrogen orthoarsenate, Zr(HAs04)2, appears to be formed slowly by adsorption of arsenic acid by zirconium dioxide.6... 

Shishkin, D.N., Galkin, B.Ya.,Fedorov,Yu.S.,Zilberman, B.Ya.,Shmidt,O.V.Partitioning of high-level waste with an extractant based on chlorinated cobalt dicarbollide and dibu-tylphosphoric acid zirconium salt. Radiochemistry (2003), 45 (6), 577-580. 

Shmidt, O.V., Zilberman, B.Ya., Fedorov, Yu.S., Suglobov, D.N., Puzikov, V.A., Mashkov, L.G., Palenik, Yu.V., Glekov, R.G. Extraction properties of dibutylphosphoric acid zirconium salt in recovery of transplutonium and rare-earth elements from nitric acid solution. Radiokhimiya (2002), 44 (5), 428 133. 

SYNS HYACINTH SILICIC ACID, ZIRCONIUM(4+) SALT (1 1) ZIRCON... 

To address the design criteria listed above, Kobayashi and co-workers prepared the mildly Lewis acidic zirconium[BINOL]2 complexes 78a,b from Zr(Of-Bu)4and (i )-BINOL and theimines 76 derived from 2-aminophenol [51a, 51b, 51c, 51d] (Scheme 26). In the presence of catalytic amounts of 78a the tri-methylsilyl ketene acetal of methyl 2-methylpropanoate (77) reacted with 76a to afford the adduct 79 quantitatively and with 34% ee. The use of N-methylim-idazole (NMI) in equal amoimts markedly improved the selectivity to 70% ee as did the use of 78b which provided 79 in 90% ee. By chemical correlation the products were shown to be of the i -configuration. The reaction displayed some generality with aromatic aldimines (83-98% ee), but the one enoHzable aldi-mine gave only modest results (56% yield, 80% ee) [51e]. 

NITRIC ACID, ZIRCONIUM(IV) SALT (13746-89-9) A powerful oxidizer. Incompatible with reducing agents, esters, many other substances. Dangerous explosion risk in contact with organic materials. Dusts of zirconium compounds ignite and explode in a carbon dioxide atmosphere. Attacks metals. 

EINECS 245-018-1 2-Ethylhexanoic acid, zirconium salt Hexanoic acid, 2-ethyl-, zirconium salt. 

Silane, triethyl- 3926 Silicic acid, zirconium salt 4169... 

Silane, trimethoxy- 3951 Silicic acid, zirconium(4+) salt (1 1) 4170... 

Zr(0H)As04,xH20, which may be useful as an ion-exchange matrix, has been obtained by heating arsenious acid, zirconium(iv) oxychloride, and potassium persulphate in aqueous HCl. ... 

Acetic acid vinyl ester polymers. See Polyvinyl acetate Acetic acid, zirconium salt. See Zirconium acetate Acetic aldehyde. See Acetaldehyde Acetic ester Acetic ether. See Ethyl acetate Acetic, 1,2,3-propanetriyl ester Acetin. See Triacetin Acetoacetic acid ethyl ester. See Ethylacetoacetate Acetoacetic acid, 2-hydroxyethyl ester, acrylate. See 2-(Acetoacetoxy) ethyl acrylate... 

Synonyms Acetic acid, zirconium salt Zirconyl acetate Empirical CjHjOzZr... 

Acetic acid, zinc salt. See Zinc acetate Acetic acid, zirconium salt. See Zirconium acetate... 

Sulfuric acid zinc salt (1 1). See Zinc suifate Suifuric acid zinc sait (1 1) heptahydrate. See Zinc sulfate heptahydrate Sulfuric acid, zirconium (4+) salt (2 1). See Zirconium sulfate... 

Synonyms Disulfatozirconic acid Sulfuric acid, zirconium (4+) salt (2 1) Zirconium (IV) sulfate Zirconium (IV) sulfate hydrate Zirconium sulfate tetrahydrate Zirconyl sulfate Empihcal OsS r Formula Zr(S04)2 4H2O Properties Wh. cryst. powd. sol. in water forming acidic sol ns. si. sol. in alcohol insol. in hydrocarbons m.w. 283.35 (anhyd.), 355.40 (tetrahydrate) sp.gr. 3.22 bulk dens. 70 Ib/ft m.p. 410 C tetrahydrate loses water of cryst. above 100 C... 

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