Chemical Entrapment of Divalent Lead By Ettringite
This work aims to make clear whether Pb(Ⅱ) can be chemically entrapped by ettringite and find out under what conditions this entrapment can take place. In experiment condition, several chemical analytical reagents were used to synthesize the lead analog of ettringite Pb6Al(OH)62·3SO4·26H2O, Ca-Pb ettringite (Ca,Pb)6 Al(OH)62·3SO4·26H2O and plumbite ettringite 3CaO· Al2O3·3CaPbO2·31H2O. The results showed that the lead analog of ettringite and the plumibte ettringite couldnt be synthesized, while Ca-Pb ettringite could be made. This indicated that Pb(Ⅱ) couldnt be chemically entrapped by ettringite when divalent calcium or sulfate was absent in liquid phase. However, Pb(Ⅱ) could entrapped into ettringite lattice when calcium ions existed in liquid phase to formed Ca-Pb ettringite. The X-ray diffraction patterns of Ca-Pb ettringite were significantly different from that of Ca-ettringite, indicating that ettringite lattice been varied after accommodating divalent lead. Experiments on Pb(Ⅱ) solidified by 100％ type Ⅰ clinker showed that the XRD patterns of the paste at 7-day storage period changed after they doped divalent lead, These further confirmed that Pb(Ⅱ) could be entrapped into cement minerals including ettringite.
ettringite entrapment divalent lead
Junkang Lan Kai Ding Meng Wu Baojian Liu
Department of Resources and Environmental Engineering,Guilin University of Technology Jian-Gan Road 12,Guilin 541004,P.R.China
国际会议
北京
英文
1-5
2009-06-11（万方平台首次上网日期，不代表论文的发表时间）