TY - JOUR

T1 - Buffered cyclodextrin extraction of -phenanthrene from black carbon amended soil

AU - Yu, Linbo

AU - Vázquez-Cuevas, Gabriela

AU - Duan, Luchun

AU - Semple, Kirk T.

N1 - This is the author’s version of a work that was accepted for publication in Environmental Technology and Innovation. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Environmental Technology and Innovation, 6, 2016 DOI: 10.1016/j.eti.2016.09.002

PY - 2016/11

Y1 - 2016/11

N2 - The presence of black carbon (BC) in soil drastically reduced the mineralisation of 14 C -phenanthrene and its extractability by hydroxypropyl- β -cyclodextrin (HPCD) extractions. This study also tested the effects of pH on the HPCD extraction of 14 C -phenanthrene in soils with BC. Extractions using 60 mM HPCD solutions prepared in deionised water (pH 5.89) and phosphate buffers (pH 7 and 8) were conducted on 14 C -phenanthrene-spiked soils amended with three different types of BC (1% dry weight) after 1, 25, and 50 d of ageing. Biodegradation assays using a Pseudomonas sp. strain were also carried out. Results showed that after 1 and 25 d, HPCD at pH 7 extracted significantly more 14 C -phenanthrene ( p < 0.05 ) from BC-amended soils than the other two solutions (un-buffered and pH 8), while HPCD at pH 8 extracted statistically similar ( p > 0.05 ) amounts of phenanthrene compared to the un-buffered solution. At 50 d, HPCD at pH 8 generally extracted more 14 C -phenanthrene from all treatments. It was proposed that higher pH promoted the dissolution of soil organic matter (SOM), leading to a greater solubility of phenanthrene in the solvent phase and enhancing the extractive capability of HPCD solutions. Although correlations between extractability and biodegradability of 14 C -phenanthrene in BC-amended soils were poor, increasing pH was demonstrated a viable approach to enhancing HPCD extractive capability for the 14 C -PAH from soil with BC.

AB - The presence of black carbon (BC) in soil drastically reduced the mineralisation of 14 C -phenanthrene and its extractability by hydroxypropyl- β -cyclodextrin (HPCD) extractions. This study also tested the effects of pH on the HPCD extraction of 14 C -phenanthrene in soils with BC. Extractions using 60 mM HPCD solutions prepared in deionised water (pH 5.89) and phosphate buffers (pH 7 and 8) were conducted on 14 C -phenanthrene-spiked soils amended with three different types of BC (1% dry weight) after 1, 25, and 50 d of ageing. Biodegradation assays using a Pseudomonas sp. strain were also carried out. Results showed that after 1 and 25 d, HPCD at pH 7 extracted significantly more 14 C -phenanthrene ( p < 0.05 ) from BC-amended soils than the other two solutions (un-buffered and pH 8), while HPCD at pH 8 extracted statistically similar ( p > 0.05 ) amounts of phenanthrene compared to the un-buffered solution. At 50 d, HPCD at pH 8 generally extracted more 14 C -phenanthrene from all treatments. It was proposed that higher pH promoted the dissolution of soil organic matter (SOM), leading to a greater solubility of phenanthrene in the solvent phase and enhancing the extractive capability of HPCD solutions. Although correlations between extractability and biodegradability of 14 C -phenanthrene in BC-amended soils were poor, increasing pH was demonstrated a viable approach to enhancing HPCD extractive capability for the 14 C -PAH from soil with BC.

KW - Black carbon

KW - Phenanthrene

KW - Hydroxypropyl- β -cyclodextrin extraction (HPCD)

KW - Mineralisation

KW - pH

U2 - 10.1016/j.eti.2016.09.002

DO - 10.1016/j.eti.2016.09.002

M3 - Journal article

VL - 6

SP - 177

EP - 184

JO - Environmental Technology and Innovation

JF - Environmental Technology and Innovation

SN - 2352-1864

ER -