利用磷石膏制备轻质材料初探

Study on New Type Phosphogypsum Lightweight Porous Material

将重烧镁砂、磷酸二氢钾配制成磷酸镁胶凝材料（MKP）,再掺入适量的未经处理的磷石膏和微量引气剂,制备出了MKP基磷石膏轻质材料.研究了MKP的力学性能.在最优配合比的基础上,磷石膏掺量为25%～50%（质量分数）时,可获得性能较为理想的轻质材料.借助于XRD,SEM等测试技术,分析了磷石膏掺量与轻质材料性能的关系.

A lightweight porous material was prepared by incorporating dead-burnt magnesia（MgO）,monopotassium dihydrogen phosphate（KH2PO4）,with little air-entraining agents and different content of the phosphogypsum（PG） added.Magnesium phosphate cement（MKP） is a binder that can be used as the matrix to bind any inorganic waste material such as PG.First of all,the mechanical properties of the matrix were investigated.It is found that the mole ratio of magnesia to monopotassium dihydrogen phosphate（nM/nP） has significant effect on the mechanical performance of matrix material,and when nM/nP is 3,the product has the highest strength.The better performance of the porous products was achieved when the content of PG is from 25%～50%（by mass）.For a typical PG loading of 30%（by mass）,it has a strength of 4.25 MPa.The mineral phase and the micro-morphology of hydrated paste were investigated by X-ray diffractometry and scanning electron microscopy（SEM）.