Determination of organic pollutants in coking wastewater by dispersive liquid-liquid microextraction/GC/MS

Abstract

A method based on dispersive liquid-liquid microextraction coupled with GC/MS was developed for quantitative analysis of the major organic pollutants listed in the United States Environmental Protection Agency method 8270 and the 15 European-priority polycyclic aromatic hydrocarbons in coking wastewater. The major parameters such as extraction solvent, dispersive solvent, solution pH, and extraction time were systematically optimized. The optimum extraction conditions were found to be: 15 μL mixture of 2:1 v/v carbon tetrachloride and chlorobenzene as the extraction solvent, 0.75 mL ACN as the dispersive solvent, solution pH of 8, and extraction time of 2 min. For the major pollutants listed in the United States Environmental Protection Agency 8270, the linear ranges were 0.1 to 100 mg/L, the enrichment factors ranged from 452 to 685, and the relative recoveries ranged from 67.5 to 103.5% with RSDs of 4.0-9.1% (n = 5) at the concentrations of 10 mg/L under the optimum extraction conditions. For the 15 polycyclic aromatic hydrocarbons, the linear ranges were 0.1 to 100 μg/L, the enrichment factors ranged from 645 to 723, and the relative recoveries ranged from 94.5 to 107.6% with RSDs of 4.6-9.0% (n = 5) at the concentrations of 10 μg/L. The usefulness of the developed method was demonstrated by applying it in the analysis of real-world coking wastewater samples.

Improvement of biodegradability for coking wastewater by selective adsorption of hydrophobic organic pollutants

“…Generally, phenols account for about 80% of the total COD amount in coking wastewater [18,19]. Song et al analyzed coking wastewater from six coking plants [20]. Results showed that the sum of concentration of phenols and anilines was 23.8 ± 3.0 mg L À1 , but the sum of 16 PAHs's concentration was 0.66 ± 0.10 mg L À1 .…”

Performance and microbial community composition in a long-term sequential anaerobic-aerobic bioreactor operation treating coking wastewater

“…Coking wastewater (CWW) generated during coke production has garnered wide attention due to its mixture of diverse organic contaminants that are hazardous to ecosystems and human health (Song et al 2013;Zhang et al 2013;Felföldi et al 2010;Zhao et al 2014;Hou et al 2015). CWW is generally treated by biological methods such as conventional activated sludge processes (Vazquez et al 2006;Maranon et al 2008).…”

Checklist of the Clubiona japonica-group spiders, with the description of a new species from China (Araneae, Clubionidae)

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