TY - JOUR
T1 - Solidification/stabilisation behaviours of Zn2+ in magnesium potassium phosphate cement
T2 - Experiments and density functional theory study
AU - Mi, Renjie
AU - Zhang, Zhibin
AU - Ji, Weiming
AU - Liu, Shichang
AU - Kai, M. F.
AU - lin, Kui
AU - Tan, Yongshan
N1 - Funding Information:
The authors are grateful for the financial support received from Applied Fundamental Research Project of Qinghai Province (Grant No. 2022-ZJ-707 ).
Publisher Copyright:
© 2023 Elsevier Inc.
PY - 2023/8/15
Y1 - 2023/8/15
N2 - The solidification/stabilisation behaviours of Zn2+ in magnesium potassium phosphate cement (MKPC) have not been thoroughly investigated. Herein, a series of experiments and a detailed density functional theory (DFT) study were conducted to investigate the solidification/stabilisation behaviours of Zn2+ in MKPC. The results showed that the compressive strength of MKPC reduced with the addition of Zn2+ because the formation of MgKPO4·6H2O (the main hydration product in MKPC) was delayed with the addition of Zn2+, as discovered by the crystal characteristics, and because Zn2+ exhibited a lower binding energy in MgKPO4·6H2O compared to Mg2+, as revealed by DFT results. Additonally, Zn2+ had little influence on the structure of MgKPO4·6H2O, and Zn2+ existed in MKPC as the formation of Zn2(OH)PO4, which was decomposed in the range of around 190–350 °C. Moreover, there were a lot of well-crystallised tabular hydration products before the addition of Zn2+, but the matrix was comprised of irregular prism crystals after adding Zn2+. Furthermore, the leaching toxicity of Zn2+ of MKPC was much smaller than the requirements of Chinese and European standards.
AB - The solidification/stabilisation behaviours of Zn2+ in magnesium potassium phosphate cement (MKPC) have not been thoroughly investigated. Herein, a series of experiments and a detailed density functional theory (DFT) study were conducted to investigate the solidification/stabilisation behaviours of Zn2+ in MKPC. The results showed that the compressive strength of MKPC reduced with the addition of Zn2+ because the formation of MgKPO4·6H2O (the main hydration product in MKPC) was delayed with the addition of Zn2+, as discovered by the crystal characteristics, and because Zn2+ exhibited a lower binding energy in MgKPO4·6H2O compared to Mg2+, as revealed by DFT results. Additonally, Zn2+ had little influence on the structure of MgKPO4·6H2O, and Zn2+ existed in MKPC as the formation of Zn2(OH)PO4, which was decomposed in the range of around 190–350 °C. Moreover, there were a lot of well-crystallised tabular hydration products before the addition of Zn2+, but the matrix was comprised of irregular prism crystals after adding Zn2+. Furthermore, the leaching toxicity of Zn2+ of MKPC was much smaller than the requirements of Chinese and European standards.
KW - Heavy metals
KW - Leaching toxicity
KW - Magnesium potassium phosphate cement
KW - Solidification/stabilisation behaviours
UR - http://www.scopus.com/inward/record.url?scp=85162839962&partnerID=8YFLogxK
U2 - 10.1016/j.envres.2023.116247
DO - 10.1016/j.envres.2023.116247
M3 - Journal article
C2 - 37245576
AN - SCOPUS:85162839962
SN - 0013-9351
VL - 231
JO - Environmental Research
JF - Environmental Research
M1 - 116247
ER -