Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6580454 | Chemical Engineering Journal | 2018 | 27 Pages |
Abstract
Electrokinetic in situ chemical oxidation (EK-ISCO) is an innovative and effective method for removing petroleum contaminants from soil. However, the high cost of exogenous oxidants is one of the main drawbacks of this technology. In this research, a new approach for the electrokinetic (EK) delivery anodic in situ generation of an oxidant was designed with the aim of solving this problem. Six EK experiments lasting 15 d with different electrolytes (NaCl or NaNO3) and different voltage potentials were performed in order to evaluate the feasibility of this approach. It was found that active chlorine was produced by a dimensionally stable anode and a NaCl solution, and can contribute to remediate sand spiked with diesel fuel (10â¯g/kg) during EK-ISCO. The obtained results showed that an increase in NaCl electrolyte concentration (from 10 to 40â¯g/L) increases the maximum concentration of active chlorine in the aqueous sand matrix (from 12.5 to 30â¯mmol/L). The diesel removal efficiencies were increased from 33% to 44% for 1â¯V/cm and from 43% to 67% for 2â¯V/cm, respectively, by using 20â¯g/L NaCl compared to using 20â¯g/L NaNO3. Vial tests also confirmed that the anodic in situ generated active chlorine in the electrolyte solution had the effect of oxidizing alkanes of diesel. The products had a higher solubility due to the inclusion of polar functional groups. Under optimal conditions, the energy consumption for removing 1% of contaminants was approximately 2â¯kâ¯Wh/ton. Consequently, the EK delivery of anodic in situ generated active chlorine can be considered as a new cost-effective method for removing organic contaminants from porous media.
Keywords
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Yue Song, Long Cang, Guodong Fang, Syed Tahir Ata-Ul-Karim, Hongting Xu, Dongmei Zhou,