Stimulation of Extraction of Diamonds with Weak and Anomalous Luminescence in X-Ray Fluorescent Separation Using Luminophore-Bearing Compositions

The authors identified the cause of loss of diamonds with nonstandard natural luminescence intensity in X-ray fluorescent separation. The technology of adjusting spectral and kinetic characteristics of diamonds is developed as treatment of diamond-bearing kimberlite material with luminophore-bearing reagents including mixture of FL-530-type luminophores and anthracene. For reaching improved stability of luminophore-bearing compositions and for the better attachment of luminophores on diamond surface, it is proposed to enhance their oil receptivity by treating with a hydrophobization agent (potassium butyl xanthate). It is suggested to ensure maximal selectivity of X-ray fluorescent separation through prevention of adhesion of luminophore-bearing composition to kimberlite grains by adding dispergators at concentrations of 1–1.5 g/l. It is shown that hydrophobization of luminophore FL-530 by potassium butyl xanthate and the use of dispergators ensure selective attachment of luminophore at the surface of diamonds with nonstandard natural luminescence, as well as their selective extraction to concentrate. The overall reduction in the loss of diamonds in X-ray fluorescent separation is proved.