Vanadyl sulphate

Vanadium IV) forms blue VOSO4, (0, 3 and 5H2O), vanadyl sulphate, which forms ranges of double salts, Prepared by SO, reduction of V2O5 in H2SO4. 

Imperatorin (Fig. 4), a furanocoumarin produced hy Angelika dahurica var. formosana plants, is traditionally used in China for treating headaches and psoriasis. The combined treatment of A. dahurica cell cultures with 30-mg/L vanadyl sulphate and 20-g/L adsorvent amberlite XAD-7 resin provided -0.5 mg of imperatorin/g dw. ... 

B. Wet Processes.—These vary considerably in detail according to the nature and amount of constituents other than vanadium in the ore. An outline of the operations involved in the case of patronite is as follows The ore is roasted with common salt or sodium carbonate and then extracted either (a) with water to give an alkaline solution of sodium vanadate and soluble vanadates of other metals, any lead, zinc, copper, etc., being left in the residue or (b) with sulphuric acid to produce a solution of vanadyl sulphate. Acid extraction is usually employed when the vanadium content of the material is low. The alkaline extract from (a) is treated with excess of sodium carbonate in order to precipitate calcium and aluminium, after removal of which,... 

Acid Vanadous Sulphates and double vanadous sulphates.—Electrolytic reduction of solutions of vanadyl sulphate, V0S04, has given two green, crystalline, acid vanadous sulphates, according to the amount of sulphuric acid also added ... 

When the reduction of the vanadyl sulphate is allowed to proceed in the presence of the sulphates of the alkali metals or of thallium, two series of double salts are obtained, the composition of which again varies with the amount of sulphuric acid present and with the other conditions. 

By heating the alkali vanadyl sulphates, compounds have been obtained which can be looked upon either as the dehydrated forms of members of this series, or as salts of the acid sulphate, HV(S04)2, mentioned above 5... 

Vanadyl Sulphates.—By treating hypovanadic oxide, V02, with sulphuric acid at about 200° C., or by reducing a sulphuric acid solution... 

Double Salts of Vanadyl Sulphate.—Two series of double salts of... 

A compound intermediate in composition between vanadic sulphate and vanadyl sulphate has been obtained by reducing a solution of a vanadic salt in sulphuric acid with sulphur dioxide, or by mixing solutions of the pentoxide and the dioxide in sulphuric acid.1... 

Vanadyl Dithionate, VOS2Oe, is prepared by treating a solution of vanadyl sulphate with barium dithionate. It decomposes on standing, with evolution of sulphur dioxide.2... 

Vanadium Nitrates.—No nitrates of vanadium have been isolated. When hypovanadic oxide is dissolved in nitric acid the blue solution which results probably contains vanadyl nitrate, V0(N03)2, but on evaporation oxidation ensues and hydrated vanadium pentoxide is obtained. Blue solutions of vanadyl nitrate arc more conveniently obtained by precipitating vanadyl chloride with silver nitrate or vanadyl sulphate with barium nitrate. Addition of nitric acid to hexammino-vanadium trichloride yields hexammino-vanadium nitrate,10 [V (NH3)6](N03)3. 

Normal carbonates of vanadium are unknown. An unstable ammonium vanadyl carbonate, of composition 3(NH4)2C0S.7V02.5C02. 16H20, has been obtained in small, violet crystals by the addition of ammonium carbonate to a neutral solution of vanadyl sulphate.4... 

A vanadium borate of uncertain composition is obtained by fusing a mixture of vanadium pentoxidc and boric anhydride. It forms green or yellowish-green crystals which, however, undergo hydrolysis readily.2 A vanadyl borate is also obtained by the action of borax on vanadyl sulphate solution,3 and a complex vanadium borotungstate has been prepared. 

Battell, M.L., V.G. Yuen, and J.H. McNeill. 1992. Treatment of BB rats with vanadyl sulphate. Pharmacol. Commun. 1 291-301. 

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