Instrument calibration parameters.

Petroleum hydrocarbon (TPH) contamination at industrial sites poses severe ecological and health risks to humans. However, conventional persulfate oxidation suffers from low efficiency and high oxidant demand requirements. To address this limitation, we employed citric acid-FeSO₄-modified sodium persulfate (FNS) for soil remediation.In this study, the petroleum hydrocarbon (TPH)-contaminated soil of a chemically contaminated site was used as the test object, and sodium persulfate modified by citric acid-FeSO4 (FNS) was selected as the oxidant. Based on laboratory tests, quantifying TPH degradation efficiency, soil pH variation, and sulfate leaching concentrations, the effects of oxidant dosage, oxidant dosage times, and CaO dosage on the remediation effect of petroleum hydrocarbon-contaminated soil were systematically investigated. The results demonstrated that citric acicd-FeSO4 significantly enhanced sodium persulfate activation (p 42- leaching concentration standard, among other things. The restored soil needs to be conditioned with CaO neutralization. In addition, FNS must be applied at one time and cannot be applied separately.