Vanadium Zirconium hydroxide

The preparation of lyophilic sols is easy and most of the time a mixture of the dispersion medium and the substance to be dispersed need only be stirred. Gelatine, for example, disperses almost spontaneously in water. The hydroxides of iron, aluminium, chromium and zirconium as well as vanadium pentoxide and silicic acids all belong to the group of hydrophilic colloids. 

Bis(cyclopentadienyl)bis(pentafluorophenyl)zirconium, 3824 Bis(cyclopentadienyldinitrosylchromium), 3269 Bis(cyclopentadienyl)hexafluoro-2-butynechromium, 3629 Bis(cyclopentadienyl)lead, 3288 Bis(cyclopentadienyl)magnesium, 3271 Bis(cyclopentadienyl)manganese, 3272 Bis(cyclopentadienyl)niobium tetrahydroborate, 3318 Bis(cyclopentadienyl)pentafluorophenylzirconium hydroxide, 3696 Bis(cyclopentadienyl)phenylvanadium, 3698 Bis(cyclopentadienyl)titanium selenate, 3287 Bis(cyclopentadienyl)tungsten diazide oxide, 3279 Bis(cyclopentadienyl)vanadium diazide, 3280 Bis(cyclopentadienyl)zirconium, 3290 Bis(l,2-diaminoethane)diaquacobalt(III) perchlorate, 1787 Bis(l,2-diaminoethane)dichlorocobalt(III) chlorate, 1780 Bis(l,2-diaminoethane)dichlorocobalt(III) perchlorate, 1781 c/i-Bisf 1,2-diaminoethane)dinitrocobalt(III) iodate, 1782 Bis(l,2-diaminoethane)dinitrocobalt(III) perchlorate, 1778 Bis(l,2-diaminoethane)hydroxooxorhenium(V) perchlorate, 1785 Bis(l, 2-diaminopropane)-ds-dichlorochromium(III) perchlorate, 2609 1,10-Bis(diazonio)decaboran(8)ate, 0197... 

Aluminum is the third most abundant element in the earth s crust (after oxygen and silicon), accounting for 8.2% of the total mass. It occurs most commonly in association with silicon in the aluminosilicates of feldspars and micas and in clays, the products of weathering of these rocks. The most important ore for aluminum production is bauxite, a hydrated aluminum oxide that contains 50% to 60% AI2O3 1% to 20% FeiOs 1% to 10% silica minor concentrations of titanium, zirconium, vanadium, and other transition-metal oxides and the balance (20% to 30%) water. Bauxite is purified via the Bayer process, which takes advantage of the fact that the amphoteric oxide alumina is soluble in strong bases but iron(III) oxide is not. Crude bauxite is dissolved in sodium hydroxide... 

Justification. Investigation of a number of gelatinous hydrous metal oxides (frequently called hydroxides, although their full structures are uncertain) has established ( ) that hydrous titanium (IV), zirconium (IV), iron (III), vanadium (III) and tin (II) oxides at least are capable of forming with enzymes insoluble complexes which are enzymically active. From the practical viewpoint hydrous titanium (IV) and zirconium (IV) oxides proved the most satisfactory. Comparatively high retentions of enzyme specific activity may be achieved (3, 4, 5). Such hydrous metal oxide materials have also proved to be suitable for the immobilisation of amino acids and peptides ( ), antibiotics with retention of antimicrobial activity ( ), polysaccharides J ), etc. 

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