The combined effects of surfactant solubilization and chemical oxidation on the removal of polycyclic aromatic hydrocarbon from soil

Abstract

A method for the remediation of polycyclic aromatic hydrocarbons (PAHs) contaminated soils was proposed involving a combination of surfactant-aided soil washing and chemical oxidation by activated persulfate (SP). In this study, Triton X-100 (TX-100) and SP was applied to the soil, either concurrently or sequentially. Results indicated that surfactant followed by amendment with a solution of SP, TX-100 + SP(l), was most effective in decreasing PAHs concentrations in a sandy loam soil (SS) and a silty clay soil (NS) from 1220 mg/kg and 2730 mg·kg to 414 mg·kg and 180 mg·kg, respectively. Compared with extraction alone and oxidation alone, TX-100 + SP(l) increased the removal of PAHs by 10-20%. TX-100 improved the degradation of 3-4 ring PAHs (M-PAHs) and 5-6 ring PAHs (H-PAHs) in SS, by approximately 8%-11%. The oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) including furans and xanthene exhibited greater reductions in soil when amended with the TX-100 and SP, than under TX-100 extraction or SP oxidation alone. Overall, increased removal of PAHs in contaminated soil can occur through simultaneous application of TX-100 and SP, relative to the sole use of TX-100 or SP. The sequential combination of surfactant and oxidant was most effective for the elimination of PAHs, especially for M-PAHs and H-PAHs in sandy loam contaminated soil.

Effect of various chemical oxidation reagents on soil indigenous microbial diversity in remediation of soil contaminated by PAHs

“…In the combined systems, in situ bacteria may use PAHs and their oxidation byproducts as carbon sources for their growth, resulting in further reduction of PAHs concentrations in the soil (Lee and Hosomi, 2001). It has been reported in the literature that the priority byproduct was oxy-PAHs included furan, xanthene and thiophene by chemical oxidation (Li et al, 2019). The transformation of PAHs to more biodegradable substrates in oxidation systems has been reported in previous studies.…”

Removal of Bound PAH Residues in Contaminated Soils by Fenton Oxidation

“…PAHs have generated extreme concern due to their toxicity, teratogenicity, carcinogenicity, and mutagenesis to humans and the wider environment. They are mainly released by incomplete combustion of fossil fuels or activities in the petrochemical industry, including crude oil refining, coal tar production, and asphalt production [4,5]. Owing to their high hydrophobicity and persistence, soils are the ultimate repository of PAHs with concentration up to hundreds of mg/kg in many countries [6,7].…”

Phenanthrene decomposition in soil washing effluents using UVB activation of hydrogen peroxide and peroxydisulfate

“…Polycyclic aromatic hydrocarbons (PAHs), as a class of HOCs, are ubiquitous in the soil environment due to their low solubility in water and long-term persistence in soils (Manoli and Samara 1999;Shin et al, 2006;Trellu et al, 2016). Phenanthrene (PHE), containing three benzene rings, is one of the most widely detected PAHs in the contaminated sites (Bezza and Chirwa 2017;Gou et al, 2019;Li et al, 2019;Petrová et al, 2017), especially those located in manufactured gas plants and coal tar refinery (Li et al, 2019;Reddy et al, 2006;Yeom et al, 1995). Therefore, it is urgent and essential to develop effective remediation strategies to restore PAHs contaminated soil.…”