THERMAL INVESTIGATIONS ON PHASE TRANSFORMATIONS OF SYRIAN PHOSPHORITE. PART II.

摘要

The phase and structural transformations of Syrian phosphorite subjected to mechano-chemical activation are investigated in this study by means of powder XRD and thermal analyses. The results give evidence for intensive isomorphous substitutions in the apatite structure during the activation period leading to decrease of its local stability, formation of energy accumulated metastable phase of lowered degree of crystallinity, and increased solubility of the activated sample in 2% citric acid as compared with that one of the starting material. The results from the physical and chemical analysis of the investigated here sample activated by milling bodies worked out by plain steel give evidence for lower mechanochemical effect as compared to that one for the sample activated through analogous in size, however, Cr-Ni alloy steel milling bodies. The latter are characterised by bigger specific density which is the reason to promote intensification of the mechanochemical transformations independently of the similar milling bodies size. The registered phase and structural changes are prerequisite to continue studies on the productivity at the plants and assimilation of nutrients with mechanochemically activated phosphorate samples. In this connection the results from a vegetation experiment which is to be made, will be the subject of our next paper.