关键词: 含砷废渣;地聚物;硫酸钠;干湿循环

Abstract: Phosphorous slag and fly ash based geopolymer was used to immobilize the arsenic-containing waste residue discharged from a nonferrous metallurgical process.The effects of the concentration of sodium sulfate on the mass change,compressive strength and arsenic leaching concentration of the solidified forms were investigated.Meanwhile,the phase composition and microstructure of the solidified forms were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM).After aging for 4 cycles in the sodium sulfate solution,the compressive strength can be improved by 11％-21％.When the dry wet-cycle is 5-8 times,structure of geopolymeric matrix was destroyed,which is leaded to the compressive strength of solidified body decreases by 5％-20％ and the arsenic leaching concentration increases by O.3％.Thus the property of solidified form is stable in sodium sulfate solution.

Key words: arsenic-containing waste;geopolymer;sodium sulfate;dry-wet cycles