To investigate the efficacy and strength properties of Fe²⁺-activated persulfate remediation for 1

2-dichlorobenzene-contaminated soil with varying persulfate concentrations

we conducted degradation

microscopic

particle size

liquid-plastic limit

unconfined compressive strength (UCS)

and undrained shear tests. The results indicate that adding 15.0% Fe²⁺-activated persulfate achieves a 92.59% removal rate of 1

2-dichlorobenzene. Furthermore

the reaction produces sodium sulfate

calcium sulfate

and ferric hydroxide. Small amounts of sodium sulfate and calcium sulfate fill the pores between soil particles

leading to a denser soil structure. However

the expansive effect of excessive sodium sulfate crystals weakens the inter-particle cohesion

leading to soil loosening. After remediation

the clay content increases

while the silt and sand content decreases. The liquid limit

the plastic capacity and the plastic index increase

while the plastic limit decreases with the increase of the persulfate dosage. The UCS and the maximum shear stress decrease with the increase of the persulfate dosage. The UCS of the soil treated by 10.0% persulfate is 310.75 kPa

20.34% higher than the strength of untreated soil. The maximum deviator stress at shear failure is 142.73 kPa.