PRODUCTS OF REACTIONS OF MO AND ZR COMPOUNDS IN MOLTEN NITRATE

Reactions of Mo and Zr compounds in molten nitrate media have been stu died. It has been shown that an interaction between Zr-IV and Mo-VI sp ecies occurs in nitrate melts, leading to the formation of high-surfac e-area mixed-oxide solids containing dispersed molybdate species graft ed onto small zirconia particles. The physico-chemical properties of t he products were studied vs. reaction temperature, nature of the alkal i-metal cation and Mo reactant. The reaction temperature was of primar y importance in determining the composition and structure of the produ ct. At 30 degrees C, amorphous zirconia with randomly distributed mono molybdate species was formed, whereas at 500 degrees C crystalline ZrO 2 superficially modified by polymolybdate was obtained. The alkali-met al cation influenced the amount of Mo in the solid and its dispersion.