In-depth investigation of Sodium percarbonate as oxidant of PAHs from soil contaminated with diesel oil

Jorge Vinicius Fernandes Lima Cavalcanti; Tiago José Marques Fraga; Mirella de Andrade Loureiro Leite; Daniella Fartes Dos Santos E Silva; Valmir Félix de Lima; Alexandre Ricardo Pereira Schuler; Clístenes Williams Araújo do Nascimento; Maurício Alves da Motta Sobrinho

doi:10.1016/j.envpol.2020.115832

In-depth investigation of Sodium percarbonate as oxidant of PAHs from soil contaminated with diesel oil

Environ Pollut. 2021 Jan 1;268(Pt B):115832. doi: 10.1016/j.envpol.2020.115832. Epub 2020 Oct 14.

Authors

Jorge Vinicius Fernandes Lima Cavalcanti¹, Tiago José Marques Fraga², Mirella de Andrade Loureiro Leite³, Daniella Fartes Dos Santos E Silva³, Valmir Félix de Lima³, Alexandre Ricardo Pereira Schuler³, Clístenes Williams Araújo do Nascimento⁴, Maurício Alves da Motta Sobrinho⁵

Affiliations

¹ Department of Chemical Engineering, Federal University of Pernambuco, 1235 Prof. Moraes Rego Avenue, Cidade Universitária, ZIP code, 50670-901, Recife, Brazil. Electronic address: jorge.cavalc@ufpe.br.
² Department of Chemical Engineering, Federal University of Pernambuco, 1235 Prof. Moraes Rego Avenue, Cidade Universitária, ZIP code, 50670-901, Recife, Brazil. Electronic address: tiago.fraga2012@gmail.com.
³ Department of Chemical Engineering, Federal University of Pernambuco, 1235 Prof. Moraes Rego Avenue, Cidade Universitária, ZIP code, 50670-901, Recife, Brazil.
⁴ Department of Agronomy, Federal Rural University of Pernambuco, Dom Manoel de Medeiros Street, W/N Dois Irmãos, ZIP code, 52171-011, Recife, Brazil. Electronic address: clistenes.nascimento@ufrpe.br.
⁵ Department of Chemical Engineering, Federal University of Pernambuco, 1235 Prof. Moraes Rego Avenue, Cidade Universitária, ZIP code, 50670-901, Recife, Brazil. Electronic address: mottas@ufpe.br.

PMID: 33120152
DOI: 10.1016/j.envpol.2020.115832

Abstract

Sodium percarbonate (SPC, 2Na₂CO₃∙3H₂O₂), is a compound that can be used under multiple environmental applications. In this work, SPC was employed as oxidant in the treatment of soil contaminated with diesel oil. The soil samples were collected during the earthmoving stage of RNEST Oil Refinery (Petrobras), Brazil. Then, the samples were air-dried, mixed and characterized. Subsequently, raw soil was contaminated with diesel and treated by photo-Fenton reaction (H₂O₂/Fe²⁺/UV). SPC played a significant role in the generation of hydroxyl radicals under the catalytic effect of ferrous ions (Fe²⁺), hydrogen peroxide (H₂O₂) and radiation. These radicals provoked the photodegradation of polycyclic aromatic hydrocarbons (PAHs), in the soil remediation. A factorial design 3³ was carried out to assess the variables which most influenced the decrease in total organic carbon (TOC). The study was performed with the following variables: initial concentration of [H₂O₂] and [Fe²⁺], between 190.0 and 950.0 mmol L^-1 and 0.0-14.4 mmol L^-1, respectively. UV radiation was supplied from sunlight, blacklight lamps, and system without radiation. All experiments were performed with 5.0 g of contaminated soil in 50.0 mL of solution. The initial concentration of Fe²⁺ showed the statistically most significant effect. The oxidation efficiency evaluated in the best condition showed a decrease from 34,765 mg kg^-1 to 15,801 mg kg^-1 in TOC and from 85.750 mg kg^-1 to 20.770 mg kg^-1 in PAHs content. Moreover, the sums of low and high molecular weight polycyclic aromatic hydrocarbons (LMW-PAHs and HMW-PAHs) were 19.537 mg kg^-1 and 1.233 mg kg^-1, respectively. Both values are within the limits recommended by the United Sates Environmental Protection Agency (USEPA) and evidenced the satisfactory removal of PAHs from contaminated soil, being an alternative to classic oxidation protocols.

Keywords: Advanced oxidation processes; Diesel oil; Fenton oxidation; Polycyclic aromatic hydrocarbons; Sodium percarbonate; Soil remediation.

MeSH terms

Brazil
Carbonates
Hydrogen Peroxide
Oxidants
Photolysis
Polycyclic Aromatic Hydrocarbons* / analysis
Soil
Soil Pollutants* / analysis

Substances

Carbonates
Oxidants
Polycyclic Aromatic Hydrocarbons
Soil
Soil Pollutants
Hydrogen Peroxide
sodium percarbonate