Silver metavanadate

It has been stated that the results obtained by precipitation of vanadate as silver orthovanadate Ag3V04 are not altogether satisfactory. Better results are obtained by precipitation at pH 4.5 as silver metavanadate AgV03 the precipitate is weighed after drying at 100-105 °C. 

Basic Silver Metavanadate, SAg20.2V205 or Ag20.4AgV03, is prepared by the action of silver nitrate on the corresponding sodium salt. It is a dark yellow compound, almost insoluble in water.8... 

Silver Metavanadate, AgV03, is a yellow, gelatinous substance obtained by interaction between silver nitrate and a metavanadate in neutral solution. It is soluble in nitric acid and in ammonia.5... 

The gravimetric estimation of vanadium in alkaline vanadate solutions has also been effected by precipitating as ammonium metavanadate in the presence of ammonium chloride.6 Precipitation is incomplete, however, unless the solution is quite saturated with ammonium chloride 7 the addition of alcohol is recommended.8 Other gravimetric processes which have been investigated include the precipitation of barium pyrovanadate,9 precipitation of silver metavanadate,10 precipitation of manganese pyrovanadate,11 and the use of cupferron.12... 

Volkov, V.L., A.A. Fotiev, N.G. Sharova, and L.L. Surat. 1976. Phase diagram of the vanadium pentoxide-silver metavanadate system. Russian J. Inorg. Chem. 21 1566-1567. 

Determination of vanadium as silver vanadate Discussion. Vanadates are precipitated by excess of silver nitrate solution in the presence of sodium acetate after boiling, the precipitate consists of silver orthovanadate. The following reactions occur with a solution of a metavanadate ... 

The oxidation of inexpensive olefins to maleic anhydride is of economic interest, since apparently it is competitive with the oxidation of benzene to maleic anhydride in some locations. As yet, however, oxidation of C4 hydrocarbons to maleic anhydride has given only about 50 % of the theoretically possible conversion to the desired product. Bretton, Wan, and Dodge 12) examined the oxidation of several C4 olefins over silver and silver oxide catalysts, but found only traces of products other than COg and HgO. With a vanadium catalyst prepared by decomposition of ammonium metavanadate on low-area alumina, substantial yields of intermediate products were found. Longfield and Dixon 57) and Matsumoto and co-workers 156) reported similar results a summary is given in Table XIV. These reactions were usually... 

Silver iodide Sodium acetate anhydrous Sodium acetate trihydrate Sodium borate Sodium borate decahydrate Sodium bromide Sodium hydrosulfite Sodium metavanadate Stannous chloride anhydrous Tannic acid... 

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