Ion-adsorption type rare earth tailings for preparation of alkali-based geopolymer with capacity for heavy metals immobilization

Zhang，Baifa1,2,3; Yu，Ting1,3; Deng，Liangliang4; Li，Yun5; Guo，Haozhe6; Zhou，Junming1,3; Li，Lijuan2; Peng，Yuan1,3,7

2022-11-01

10.1016/j.cemconcomp.2022.104768

CEMENT & CONCRETE COMPOSITES   Impact Factor & Quartile

0958-9465

1873-393X

Ion-adsorption type rare earth tailings (RET), a type of solid waste that contains clay minerals, were used as a starting material to prepare alkali-based geopolymer. The effects on the compressive strength of RET-based geopolymer, including the modulus and concentration of the alkaline activator, curing temperature, and liquid/solid ratio, were investigated. Pb and Cd were added during the preparation of the RET-based geopolymer for evaluating the immobilization capacity of heavy metals in the as-obtained geopolymer. The results showed that geopolymer with a compact and dense microstructure was obtained through the optimization of the above factors, with the highest compressive strength being 28.5 MPa. The leaching test indicated that the RET-based geopolymer possessed a desirable capacity for immobilizing heavy metals, where the immobilization efficiency of Pb was above 99% and that of Cd ranged from 92% to 96%. Heavy metals were immobilized in the RET-based geopolymer matrix through the formation of chemical bonds (T (Si, Al)–O–M (Pb, Cd)) or through an electrostatic attraction between the metal cations and negatively charged [AlO].

Clay minerals Geopolymer Heavy metals Immobilization mechanism Mine tailing

SCI

English

Others

National Natural Science Foundation of China[41972045];National Natural Science Foundation of China[52161145405];

Construction & Building Technology ; Materials Science

Construction & Building Technology ; Materials Science, Composites

WOS:000874924200003

ELSEVIER SCI LTD

MATERIALS SCIENCE

2-s2.0-85138129373

Scopus

1.CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials,Guangzhou Institute of Geochemistry,Institutions of Earth Science,Chinese Academy of Sciences,Guangzhou,510640,China
2.School of Civil and Transportation Engineering,Guangdong University of Technology,Guangzhou,510006,China
3.University of Chinese Academy of Sciences,Beijing,100049,China
4.Department of Eco-Engineering,Guangdong Eco-Engineering Polytechnic,Guangzhou,510520,China
5.Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) / Shenzhen Key Laboratory of Natural Gas Hydrates,Academy for Advanced Interdisciplinary Studies,Southern University of Science and Technology,Shenzhen,518055,China
6.Institute of Resource Comprehensive Utilization,Guangdong Academy of Sciences,Guangzhou,510650,China
7.School of Environmental Science and Engineering,Guangdong University of Technology,Guangzhou,510006,China

Zhang，Baifa,Yu，Ting,Deng，Liangliang,et al. Ion-adsorption type rare earth tailings for preparation of alkali-based geopolymer with capacity for heavy metals immobilization[J]. CEMENT & CONCRETE COMPOSITES,2022,134.

Zhang，Baifa.,Yu，Ting.,Deng，Liangliang.,Li，Yun.,Guo，Haozhe.,...&Peng，Yuan.(2022).Ion-adsorption type rare earth tailings for preparation of alkali-based geopolymer with capacity for heavy metals immobilization.CEMENT & CONCRETE COMPOSITES,134.

Zhang，Baifa,et al."Ion-adsorption type rare earth tailings for preparation of alkali-based geopolymer with capacity for heavy metals immobilization".CEMENT & CONCRETE COMPOSITES 134(2022).