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

Abstract

Chemical oxidation is a promising pretreatment step coupled with bioremediation for removal of polycyclic aromatic hydrocarbons (PAHs). The effectiveness of Fenton, modified Fenton, potassium permanganate and activated persulfate oxidation treatments on the real contaminated soils collected from a coal gas plant (263.6 ± 73.3 mg kg −1 of the Σ16 PAHs) and a coking plant (385.2 ± 39.6 mg kg −1 of the Σ16 PAHs) were evaluated. Microbial analyses showed only a slight impact on indigenous microbial diversity by Fenton treatment, but showed the inhibition of microbial diversity and delayed population recovery by potassium permanganate reagent. After potassium permanganate treatment, the microorganism mainly existed in the soil was Pseudomonas or Pseudomonadaceae. The results showed that total organic carbon (TOC) content in soil was significantly increased by adding modified Fenton reagent (1.4%-2.3%), while decreased by adding potassium permanganate (0.2%-1%), owing to the nonspecific and different oxidative properties of chemical oxidant. The results also demonstrated that the removal efficiency of total PAHs was ordered: permanganate (90.0%-92.4%) > activated persulfate (81.5%-86.54%) > modified Fenton (81.5%-85.4%) > Fenton (54.1%-60.0%). Furthermore, the PAHs removal efficiency was slightly increased on the 7th day after Fenton and modified Fenton treatments, about 14.6%, and 14.4% respectively, and the PAHs removal efficiency only enhanced 4.1% and 1.3% respectively from 1st to 15th day after potassium permanganate and activated persulfate treatments. The oxidants greatly affect the growth of soil indigenous microbes, which cause further influence for PAHs degradation by bioremediation.

Inoculation of Triticum Aestivum L. (Poaceae) with Plant-Growth-Promoting Fungi Alleviates Plant Oxidative Stress and Enhances Phenanthrene Dissipation in Soil

“…In addition, some plants can play crucial roles in PAH dissipation by favoring the proliferation of specific soil microorganisms [15]. However, the establishment of a plant in PAH-polluted soils depends on its sensitivity and interactions with microorganisms [16][17][18]. The most negative effects of PAHs on plants are related to oxidative stress through reactive oxygen species (ROS), which can lead to oxidative damage to proteins, DNA, and lipids [19][20][21].…”

FerrateVI oxidation of polycyclic aromatic compounds (PAHs and polar PACs) on DNAPL-spiked sand: degradation efficiency and oxygenated by-product formation compared to conventional oxidants

“…Permanganate is an oxidant reacting with oxido-reductive pathway (two electron transfers) known to persist (weeks to months) in soils and aquifers (de Souza e Silva et al, 2009;Huling and Pivetz, 2006;Ranc et al, 2017). It shows a long-lasting efficiency, but generates MnO2 precipitates which can alter soil permeability and can inhibit regrowth of vegetation (Sirguey et al, 2008) and can alter or change micro-organisms diversity (Liao et al, 2019). Very effective to degrade PAHs (Boulangé et al, 2019b;Lemaire et al, 2019;Liao et al, 2019Liao et al, , 2018Ranc et al, 2017), its efficiency on PACs is dependent on molecular size and aromatic condensation structure (Clar and Schoental, 1964;Forsey et al, 2010;Wang et al, 2015).…”

“…It shows a long-lasting efficiency, but generates MnO2 precipitates which can alter soil permeability and can inhibit regrowth of vegetation (Sirguey et al, 2008) and can alter or change micro-organisms diversity (Liao et al, 2019). Very effective to degrade PAHs (Boulangé et al, 2019b;Lemaire et al, 2019;Liao et al, 2019Liao et al, , 2018Ranc et al, 2017), its efficiency on PACs is dependent on molecular size and aromatic condensation structure (Clar and Schoental, 1964;Forsey et al, 2010;Wang et al, 2015). Catalyzed Hydrogen peroxide in Fenton reactions forms the hydroxyl-radical (HO), a highly reactive radical with a short lifespan, which degrades organic matter without selectivity (Ferrarese et al, 2008;Rivas, 2006;Watts et al, 2002).…”

“…Persistence in soils is usually higher for persulfate (weeks), than hydrogen peroxide (minutes to hours) as persulfate is more stable in sub-surface (Huang et al, 2002). Activated persulfate have shown high efficiency for PAHs degradation (Cassidy et al, 2015;Chen et al, 2015;Kakosová et al, 2017;Lemaire et al, 2019;Liao et al, 2019Liao et al, , 2018Peng et al, 2016;Ranc et al, 2017;Song et al, 2019). Sulfate radical-anion shows selectivity towards low molecular mass compounds (Gryzenia et al, 2009;Usman et al, 2012a).…”

Remediation of Soil Polluted by Organic Compounds Through Chemical Oxidation and Phytoremediation Combined with DCT

“…The chemical oxidation is a remediation technology successfully used for the decontamination of soils polluted by hydrocarbons [41,42,43]. It can be applied both in situ and ex situ.…”