X-Ray Diffractometric Phase Analysis of Mirabilite Alkali Mixture Prepared from High Salt Containing Waste Water

Mirabilite alkali mixture was prepared from high salt containing waste water drained from non-ferrous smelteries by simulated sunning-evaporation. The solid mixture was dried at 140 ℃ for 15 h, and a small portion of the dried mixture was pulverized and used for X-ray diffractometry (XRD). As shown by the results of XRD, 3 phases, i.e., Na2SO4 as orthogonal crystal, Na6(CO3)(SO4)2 as rhombic crystal and NaCl as cubic crystal, were found in the sample. The inorganic crystal structure database (ICSD-2006) was used in the determination of crystal-structures and related parameters of the mirabilite alkali mixture. Quantitative phase analysis of the sample was performed by applying the Rietveld method of full spectrum fitting without using standard samples of pure-phase compounds, and using the applied TOPAS software. As shown by the results, values of Rwp (18.00), Rp (14.14) and GOF (1.49) with high fitting precisions were obtained.