PMID- 34775161
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20211206
LR  - 20231108
IS  - 1873-2828 (Electronic)
IS  - 1350-4177 (Print)
IS  - 1350-4177 (Linking)
VI  - 80
DP  - 2021 Dec
TI  - Ultrasound-assisted soil washing processes using organic solvents for the 
      remediation of PCBs-contaminated soils.
PG  - 105825
LID - S1350-4177(21)00367-9 [pii]
LID - 10.1016/j.ultsonch.2021.105825 [doi]
LID - 105825
AB  - Ultrasonic soil washing processes using organic solvents were investigated for 
      the development of novel remediation technologies for persistent organic 
      pollutants (POPs)- contaminated soils. Aluminum foil erosion was first tested to 
      understand sonophysical activity in water, methanol (polar) and n-hexane 
      (nonpolar) in a 28 kHz double-bath-type sonoreactor. Significant sonophysical 
      damage on the aluminum foil was observed at the antinodes for all solvents, and 
      the order of degree of sonophysical damage was as follows: 
      water > methanol > n-hexane. Subsequently, conventional (mechanical mixing only) 
      and ultrasonic soil washing (mechanical mixing and ultrasound) techniques were 
      compared for the removal of polychlorinated biphenyls (PCBs) from soil. Two types 
      of contaminated soils, fresh (Soil A, C(0) = 2.5 mg/kg) and weathered (Soil B, 
      C(0) = 0.5 mg/kg), were used and the applied soil-to-liquid (S:L) ratio was 1:5 
      and 1:10 for methanol and n-hexane, respectively. The polar solvent significantly 
      increased washing efficiencies compared to the nonpolar solvent, despite the 
      nonpolar nature of the PCBs. Washing efficiency was significantly enhanced in 
      ultrasonic soil washing compared to conventional washing, owing to macro- and 
      micro-scale sonophysical actions. The highest washing efficiencies of 90% for 
      Soil A and 70% for Soil B were observed in the ultrasonic washing processes using 
      methanol. Additionally, a single operation of the ultrasonic washing process was 
      superior to two sequential processes with conventional mixing in terms of washing 
      efficiency, consumption of washing agents, treatment of washing leachate, and 
      operation time. Finally, the removal of PCBs in an organic solvent (methanol) was 
      investigated in photolytic and sonolytic processes for the post-treatment of soil 
      washing leachate. A photolysis efficiency of 80% was obtained within 60 min of UV 
      exposure for intensities of 1.0, 2.0, and 4.0 W/cm(2). The primary mechanism of 
      PCBs degradation is photolytic dechlorination. In contrast, no degradation was 
      detected in the sonolytic process, as the excess organic solvent acted as a 
      strong radical scavenger.
CI  - Copyright (c) 2021 The Authors. Published by Elsevier B.V. All rights reserved.
FAU - Lee, Dukyoung
AU  - Lee D
AD  - Department of Environmental Engineering, Kumoh National Institute of Technology, 
      Gumi 39177, Republic of Korea; Department of Energy Engineering Convergence, 
      Kumoh National Institute of Technology, Gumi 39177, Republic of Korea.
FAU - Son, Younggyu
AU  - Son Y
AD  - Department of Environmental Engineering, Kumoh National Institute of Technology, 
      Gumi 39177, Republic of Korea; Department of Energy Engineering Convergence, 
      Kumoh National Institute of Technology, Gumi 39177, Republic of Korea. Electronic 
      address: yson@kumoh.ac.kr.
LA  - eng
PT  - Journal Article
DEP - 20211105
PL  - Netherlands
TA  - Ultrason Sonochem
JT  - Ultrasonics sonochemistry
JID - 9433356
SB  - IM
PMC - PMC8593648
OTO - NOTNLM
OT  - Cavitation
OT  - Methanol
OT  - Polychlorinated biphenyls
OT  - Soil washing
OT  - n-Hexane
COIS- The authors declare that they have no known competing financial interests or 
      personal relationships that could have appeared to influence the work reported in 
      this paper.
EDAT- 2021/11/15 06:00
MHDA- 2021/11/15 06:01
PMCR- 2021/11/05
CRDT- 2021/11/14 20:58
PHST- 2021/08/29 00:00 [received]
PHST- 2021/10/20 00:00 [revised]
PHST- 2021/11/03 00:00 [accepted]
PHST- 2021/11/15 06:00 [pubmed]
PHST- 2021/11/15 06:01 [medline]
PHST- 2021/11/14 20:58 [entrez]
PHST- 2021/11/05 00:00 [pmc-release]
AID - S1350-4177(21)00367-9 [pii]
AID - 105825 [pii]
AID - 10.1016/j.ultsonch.2021.105825 [doi]
PST - ppublish
SO  - Ultrason Sonochem. 2021 Dec;80:105825. doi: 10.1016/j.ultsonch.2021.105825. Epub 
      2021 Nov 5.