Data evaluation of tar oil degradation using comprehensive GC²/ MS: individual compounds and principal component analysis

Abstract

BACKGROUND: Coal tar is a complex mixture of more than 100 compounds, including polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs, phenolic as well as NSO‐heterocyclic compounds (HAC). Many of these are associated with human and environmental risk. Information concerning the environmental fate of coal tar constituents, apart from the 16 PAHs listed as priority substances by the US‐EPA, is scarce. In the current study, aerobic degradation of aromatic tar oil constituents in ten historically contaminated soils was monitored under laboratory conditions using two‐dimensional comprehensive GC2/ MS. RESULTS: Fifty‐four aromatic compounds were detected in one single analysis. Degradation behavior of individual compounds was determined by their hydrophobicity, molecular size, degree of alkylation and isomeric conformation. Eight substances, including six US‐EPA PAHs and two benzofluorene isomers, were identified in nine out of ten soils as principal components in the residual contamination after degradation. CONCLUSION: Using GC2/ MS to reveal the degradation behavior of distinct coal tar constituents and applying PCA to identify contaminants resistant to microbial degradation can be useful for the optimization of bioremediation measures at contaminated sites. Copyright © 2012 Society of Chemical Industry

Extraction performance evaluation and theoretical analysis of removal of phenol from oil mixture using a dual‐functionalized ionic liquid: 1‐hydroxyethyl‐3‐methylimidazolium propionate

“…To enhance the extraction efficiency of the separation of phenol from LTCT, based on the above literature analysis, in the work reported here, the DFIL [EtOHmim][Pro] with modified cation using the OH group was prepared for the extraction of phenol from LTCT model oil, where the model oil was prepared with toluene and hexane as representative components. 21,22 The extraction conditions, including the phase ratio (m DFIL :m oil ), contact temperature and contact time, were investigated. RE was used as the index to measure the extraction performance of the prepared DFIL.…”

Enhanced Accessibility of Polycyclic Aromatic Hydrocarbons (PAHs) and Heterocyclic PAHs in Industrially Contaminated Soil after Passive Dosing of a Competitive Sorbate

“…They can be classified based on their origin as (i) petrogenic PAHs derived from liquid organic fuels before combustion, (ii) pyrogenic PAHs derived from incomplete combustion processes either on particles such as soot or in nonaqueous phase liquids (NAPL) as formed during coal gasification, and (iii) biogenic PAHs produced by certain aquatic and terrestrial microorganisms. , Since the beginning of industrialization, industrial production and economic development have been based on processing and combustion of fossil fuels. Consequently, PAHs and other petrogenic and pyrogenic products (e.g., monoaromatics) are frequently found in the environment. − PAHs, as prioritized by the United States Environmental Protection Agency (US EPA), may be found in environmental samples together with contaminants such as heterocyclic PAHs containing nitrogen, sulfur, or oxygen atoms and alkylated PAHs. − Some of these compounds are potent toxins and therefore face specific considerations …”

Composition and Dissolution of a Migratory, Weathered Coal Tar Creosote DNAPL

“…Source dissolution processes are characterized to a better extent for electron acceptor DNAPLs, such as single-component halogenated hydrocarbons (Klenk and Grathwohl, 2002;Guilbeault et al, 2005;Johnston et al, 2014). Electon donor NAPLs, including light petroleum and dense coal tar phases, consist of hundreds or even thousands of different compounds of differing environmental properties, most importantly hydrophobicity, biodegradability, toxicity, and subsurface mobility (Brown et al, 2006;Vasilieva et al, 2012a;Erlacher et al, 2013). Commonly, only a limited range of compounds is considered in modeling approaches, most prominently a selection of 16 EPA-listed PAH, which are among the most abundant constituents (Brown et al, 2006;Vasilieva et al, 2012a,b) at tar oil impacted soils, aquifers and sediments.…”