Determination of Organic Matters in Phosphogypsum and Their Influence on the Properties of Cement

For utilizing phosphogypsum effectively in cement,by measurement techniques such as infrared spectrum and color-mass spectrum et al,organic matters in phosphogypsum were analyzed qualitatively and quantitatively.Their influence on the properties of cement was also investigated.The results showed that organic matters in phosphogypsum were mainly C_5H_(10)O_3,C_2H_3O_5,C_6H_(14)O,C_5H_(10)O_2.They were physically adsorbed on the surface of phosphogypsum crystals and their content fell within the range of about 0.1%～0.2%.The presence of organic matters increased the setting time of cement and reduced the strength,particularly remarkablely in the 28 days compressive strength.Their influence could be cleaned out by floating pretreatment.