Lead metavanadate

Basic Lead Metavanadate, 8Pb0.2V206.2H20 or Pb0.2Pb(V03)a. 2H20, is obtained as a yellow powder by the action of lead nitrate on an acid manganese vanadate.9... 

Lead Metavanadate, Pb(VOg)2.—Acid solutions of vanadates on being treated with lead salts give rise to yellow basic vanadates the composition of which varies with the conditions. The precipitation of normal lead vanadate is, therefore, difficult. It has been accomplished by the addition of lead acetate to ammonium metavanadate solution in the presence of acetic acid.2 The lead precipitates contain all the vanadic acid originally present in solution, and precipitation of vanadates with lead salts has, therefore, been employed for the quantitative estimation of vanadium.3 The mineral deschenite consists chiefly of lead metavanadate a portion of the lead is, however, frequently replaced by zinc.4... 

Lead Pyrovanadate, PbaVa07.—This salt is of interest in that it is the artificial form of descloizite, one of the important natural ores of vanadium. It is obtained by boiling mixed solutions of lead nitrate and ammonium metavanadate in the presence of acetic acid.11 A pale yellow basic pyrovanadate of lead, 2PbaVa07.PbO, is obtained by... 

The use of certain vanadium compounds as catalysts has been increasing. Vanadium oxy trichloride is a catalyst in making ediylene-propylene rubber. Ammonium metavanadate and vanadium pentoxide aie used as oxidation catalysts, particularly in the production of polyamides, such as nylon, in the manufacture of H>S04 by the contact process, in the production of phdialic and maleic anhydrides, and in numerous other oxidation reactions, such as alcohol to acetaldehyde, anthracene to anthraquinone, sugar to oxalic acid, and diphenylamine to carbazole. Vanadium compounds have been used for many years 111 die ceramics field for enamels and glazes. Colors are produced by various combinations of vanadium oxide and silica, zirconia, zinc, lead, tin, selenium, and cadmium. Vanadium intermediate compounds also are used in the making of aniline Mack used by the dye industry... 

Cu(II) and ammonium metavanadate catalyst [2a, b]. The formal stoichiometries are as follows (indeed, the reaction leads not only to N2O, but also to the formation of NO and NO2) ... 

The nitric acid oxidation of cyclohexanol at low temperatures, for example, 10-15 ° C, leads to the formation of both adipomononitrolic acid and the hemihydrate of cyclohexadione (predione) rather than the a-diketone. The predione is oxidized to AA in the presence of metavanadate. 

Studies in animals support the findings that vanadium primarily effects the respiratory system. The respiratory system responds to the particulate matter by increasing the number of leukocytes which are used to clear away the foreign matter. Respiratory distress lead to death in rats following intraperitoneal injections of sodium metavanadate (Donaldson et al. 1985). 

Lead(ll) metavanadate PblVOJ, 10099-79-3 406.1 yel powder i H,0 reac HNO3... 

A marked improvement in separation is less frequently achieved with other complex-forming salts like sodium arsenite, tungstate, molybdate or metavanadate or basic lead acetate. Boric acid or borax are more often employed as impregnation agents for complex-formation. Mobeis [317 a] and Schorn [615 a] have undertaken good compilations of the results so far obtained in this field. 

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