Abstract
The article presents the results of the physico-chemical features of phosphorous agglomerates obtained by agglomeration firing of phosphorous fines with the addition of phosphate-siliceous shales and petroleum coke. IR spectrometric, X-ray fluorescence, microstructural, and element-by-element analyses of the initial and obtained materials were used to study the initial phosphate-siliceous shale and firing products. The IR spectrum of the Janatas phosphate-siliceous shale is characterized by a wide band in the range of 3400-3700 cm-1 corresponding to v(O–H). The group of intense bands 1010-1058 cm⁻1 is caused by the asymmetric stretching of the v(Si–O–Si) structural elements of silica. In the region 667-789cm–1, v(Si–O–Al) and v(Si–O–Si) deformation vibrations of the aluminosilicate phase are detected. The IR spectra of the firing product at a temperature of 1100°C are represented as a phosphate-silicate composite in which a "matrix" (Ca–P) is combined with a glassy phase (Si–O–Al). Microstructure and element-wise composition of the batch firing product phosphate:phosphate-siliceous shales:coke:oil slage at a ratio of 65:26:6:3 is characterized by the main cementing component in the form of lamellar calcium phosphate, represented by aggregates of thin crystalline plates. The detected content of Si (9.18%) and Al (2.10%) indicates the formation of aluminosilicate minerals represented by elongated or spherical hydrosilicate aggregates.