TY - JOUR
T1 - Destruction of environmentally hazardous halogenated hydrocarbons in stable ionic liquids with superoxide ion radical
AU - AlSaleem, Saleem S.
AU - Zahid, Waleed M.
AU - Alnashef, Inas M.
AU - Haider, Husnain
N1 - Funding Information:
The authors are thankful to the King Abdulaziz City for Science and Technology (KACST) for providing financial support for this research with Grant no. T-T-12-0002 to the College of Engineering, King Saud University, Saudi Arabia. We also acknowledge the support of Dr. Sarwono Mulyono from the Chemical Engineering Department, King Saud University, Saudi Arabia.
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/5/15
Y1 - 2019/5/15
N2 - Ionic liquids (ILs) have been investigated as a media for destruction of halogenated hydrocarbons (HHCs) because of their affinity to solubilize pollutants, hydrophobicity, ability to generate and maintain free radicals, and long term stability with superoxide ion radical (O2[rad]−). Three HHCs (CCl₄ CHCl3, and CHBr3) were successfully destructed by O2[rad]− in 13 hydrophobic ILs, including two piperidinium (PIP-ILs), four pyrrolidinium (PYRR-ILs), and seven ammonium-cation based ILs (AM-ILs). The effects of contact time and potassium superoxide (KO2) dose on the destruction efficiency were evaluated using analysis of variance. 1-propyl -1- methylpiperidinium, 1-octyl-1-Methylpyrrolidinium, and octyltriethylammonium paired with bis (trifluoromethylsulfonyl) imide were found to be the best performers amongst PIP-ILs, PYRR-ILs, and AM-ILs. CHCl3, CCl₄ and CHBr3 consumed about 8, 11, and 14 KO2/HHC mole ratio to achieve 95% of optimum destruction efficiency. High viscosity was identified as the main drawback of [N8881][Tf2N] and [N4441][Tf2N]. Destruction was moderately fast and steady state efficiency was achieved within 30 min. The strong correlations between empirical polarity ETN of HHCs, work as co-solvents, and destruction efficiencies were obtained with R2 values higher than 0.99. The study presents a useful insight to use ILs as alternative solvents for treatment of hazardous wastes.
AB - Ionic liquids (ILs) have been investigated as a media for destruction of halogenated hydrocarbons (HHCs) because of their affinity to solubilize pollutants, hydrophobicity, ability to generate and maintain free radicals, and long term stability with superoxide ion radical (O2[rad]−). Three HHCs (CCl₄ CHCl3, and CHBr3) were successfully destructed by O2[rad]− in 13 hydrophobic ILs, including two piperidinium (PIP-ILs), four pyrrolidinium (PYRR-ILs), and seven ammonium-cation based ILs (AM-ILs). The effects of contact time and potassium superoxide (KO2) dose on the destruction efficiency were evaluated using analysis of variance. 1-propyl -1- methylpiperidinium, 1-octyl-1-Methylpyrrolidinium, and octyltriethylammonium paired with bis (trifluoromethylsulfonyl) imide were found to be the best performers amongst PIP-ILs, PYRR-ILs, and AM-ILs. CHCl3, CCl₄ and CHBr3 consumed about 8, 11, and 14 KO2/HHC mole ratio to achieve 95% of optimum destruction efficiency. High viscosity was identified as the main drawback of [N8881][Tf2N] and [N4441][Tf2N]. Destruction was moderately fast and steady state efficiency was achieved within 30 min. The strong correlations between empirical polarity ETN of HHCs, work as co-solvents, and destruction efficiencies were obtained with R2 values higher than 0.99. The study presents a useful insight to use ILs as alternative solvents for treatment of hazardous wastes.
KW - Ammonium-based ionic liquids
KW - Halogenated Hydrocarbons
KW - Piperidinium
KW - Pyrrolidinium
KW - Superoxide ion radical
UR - http://www.scopus.com/inward/record.url?scp=85059743658&partnerID=8YFLogxK
U2 - 10.1016/j.seppur.2018.12.070
DO - 10.1016/j.seppur.2018.12.070
M3 - Article
AN - SCOPUS:85059743658
SN - 1383-5866
VL - 215
SP - 134
EP - 142
JO - Separation and Purification Technology
JF - Separation and Purification Technology
ER -
