The paper investigates the possibility of obtaining a luminescent material by heat treatment of phosphogypsum at a temperature of 800 degrees Celsius. It is shown that it is not enough to achieve the result of heating the system to a given temperature, the luminosity of the samples is practically absent.For phosphogypsum subjected to heat treatment at a temperature of 800 degrees Celsius for 60 minutes, it was found that images obtained in the presence of 50-150% moles of citric acid showed the most pronounced luminosity. The luminosity of samples with starch in the amount of 50-75 mol% was worse (by about 50%). The use of coal as a reducing agent under given conditions led to the formation of samples with the lowest luminosity. An extreme change in the dependence of luminosity on the amount of the introduced reducing agent with maxima of 25-75% (mol.) was revealed. It is suggested that the luminescent ability of the reduced phosphogypsum is associated with the formation of the composite material calcium sulfate/sulfide.
Keywords: heat treatment mode, luminescent material, phosphogypsum recycling, reducing