Experimental Study on Solidification/Stabilization of Phenol-Contaminated Soil by Geopolymer

Sodium hydroxide-excited slag curing was used to stabilize phenol-contaminated soils with different contamination levels. Unconfined compressive strength and toxic leaching tests were carried out on solidified soil specimens of different time periods. In addition, X-ray diffraction (XRD) and scanning electron microscope (SEM) tests were performed on the contaminated soils solidified for 28 days. The test results showed that (1) The strength of the slag base polymer cured phenol-contaminated soil gradually increased with time and was influenced by the level of contamination. The higher the contamination level, the lower the strength of the cured soil. (2) After the contaminated soil was stabilized by alkali-excited slag geopolymer solidification, the leaching concentrations of phenol were significantly reduced. The leaching stabilization rates showed that the lower the contamination level, the higher the stabilization rate. (3) According to XRD and SEM–EDS, the mechanism of geopolymer curing stabilized composite contaminated soil was that geopolymer with a good cage structure adsorbed phenol.