Remediation potential of immobilized bacterial strain with biochar as carrier in petroleum hydrocarbon and Ni co-contaminated soil

Remediation potential of immobilized bacterial strain with biochar as carrier in petroleum hydrocarbon and Ni co-contaminated soil

Bacteria

Hydrocarbons

Gasoline

Biodegradation

Contamination

Heavy metals

Remediation

Organic pollutants

Soil pollution

Soils

Sulfur compounds

Degradation

Sulfide minerals

Nickel compounds

The remediation of organic pollutant-heavy metal co-contaminated soil is a great challenge. Immobilized microorganism technology (IMT) is a potential approach to remediate co-contaminated soil. In this study, we evaluated the feasibility of IMT for the remediation of petroleum hydrocarbon-heavy metal nickel (Ni) co-contaminated soil. The Ni resistant and hydrocarbon-degrading bacteria strain Citrobacter sp. was added to co-contaminated soil by immobilizing on corncob biochar. The potential performance in biodegradation of petroleum hydrocarbon and changing the mobility and speciation of nickel (Ni) in soil were determined, with consideration of the influences of the soil properties and dehydrogenase activity. The results demonstrated that the degradation rate of petroleum hydrocarbons by immobilized microorganisms group (IM) was 45.52%, significantly higher than that of the free bacteria (30.15%), biochar (25.92%) and blank group (18.47%) (P0.05). At the same time, IM was more effective in immobilizing Ni in the soil by transforming available Ni to a stable fraction with a maximum residual concentration increasing by 101.50 mgkg1, and the carcinogenic nickel sulfide was not detected after remediation in IM. IM exhibited a higher level of soil dehydrogenase activity (0.3956 gmL1h1g1) than that of free bacteria (0.2878 gmL1h1g1). A linear correlation was found between the petroleum pollutants degradation rate and dehydrogenase activity (P0.05). This study indicates the effectiveness and potential of IMT application in degrading petroleum hydrocarbon and immobilizing heavy metals in co-contaminated soil. 2020 Informa UK Limited, trading as Taylor & Francis Group.

1068-1081

7

43

Environmental Technology (United Kingdom)

2022

Li, Xi

Wang, Yaxuan

Luo, Ting

Ma, Yongsong

Wang, Bing

Huang, Qiuyu

journalArticle

9593330

10.1080/09593330.2020.1815858