Mfr. Fouda et al., On the reaction between ammonium metavanadate and potassium hydrogen sulfate at different temperatures, J SOL ST CH, 145(1), 1999, pp. 128-135
The reaction products resulting from the interaction of ammonium metavanada
te and potassium hydrogen sulfate were characterized by chemical and therma
l analysis, X-ray diffraction patterns, ligand field spectra, and magnetic
susceptibility. The interaction between the two salts was found to start as
early as 50 degrees C. The identity of the products depends essentially on
the temperature and time of reaction in addition to the molar ratio of the
reactants. The product compounds were composed, in general, of bronzes and
polyvanadates in addition to some tetra- and pentavalent vanadium compound
s. The production of tetravalent vanadium compounds may arise via the inter
vention of diamagnetic dioxovanadium(V) sulfite VO2(SO3)(0.5) which is unst
able above 200 degrees C and transforms to vanadyl sulfate (VOSO4) which in
turn reacts with K2SO4 forming K2VO(SO4)(2). (C) 1999 Academic Press.