Removal of PAHs from highly contaminated soils found at prior manufactured gas operations.
Removal of PAHs from highly contaminated soil found at a manufactured gas site was evaluated using solvent washing with mixed solvents. The following solvents were considered as water miscible co-solvents in mixed solvents: ethanol, 2-propanol, acetone, and 1-pentanol. In batch solvent extraction of soil, ethanol and 2-propanol were selected as primary components of mixed solvents in addition to 1-pentanol. Using ternary solutions containing either ethanol or 2-propanol with a volume fraction of 1-pentanol ranging from 5 to 25% and a water volume fraction ranging from 5 to 30%, ethanol was more effective than 2-propanol in extracting PAHs from soil. A solvent mixture of 5% 1-pentanol, 10% water and 85% ethanol was selected as the extraction solvent. Using a 1g:4ml soil:solvent extraction ratio, extraction kinetics showed that from 65 to 90% of the extractable PAHs were removed within an hour of contact between soil and solvent. Using this 1g:4ml extraction ratio, PAHs were removed in a three-stage cross-current solvent washing process where the same batch of soil was extracted with clean solvent for 1h in each stage. PAH removals in three-stage cross-current solvent washing were comparable to PAH removals obtained with Soxhlet extraction.
Khodadoust
A P
AP
Department of Civil and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221-0071, USA.
Bagchi
R
R
Suidan
M T
MT
Brenner
R C
RC
Sellers
N G
NG
D019840:2-Propanol / Q000737:chemistry; D003033:Coal Tar / Q000737:chemistry; D004787:Environmental Pollution / Q000032:analysis / Q000517:prevention & control; D000431:Ethanol / Q000737:chemistry; D005740:Gases; D007220:Industrial Waste; D007221:Industry; D000439:Pentanols / Q000737:chemistry; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D012989:Soil Pollutants; D012997:Solvents / Q000737:chemistry; D018505:Waste Management / Q000379:methods*
D005740:Gases; D007220:Industrial Waste; D000439:Pentanols; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; D012997:Solvents; D000431:Ethanol; D003033:Coal Tar; C024999:n-pentanol; D019840:2-Propanol