Degradation of phthalate esters and acetaminophen in river sediments using the electrokinetic process integrated with a novel Fenton-like process catalyzed by nanoscale schwertmannite.
The main objective of this study was to develop and establish an in situ remediation technology coupling nano-schwertmannite/H2O2 process and electrokinetic (EK) process for the removal of phthalates (PAEs) and acetaminophen in river sediments. Test results are given as follows: (1) injection of nano-schwertmannite slurry and H2O2 (collectively, "novel oxidant") into the anode reservoir would yield ·OH radicals that then will be diffused into the sediment compartment and further transported by the electroosmotic flow and/or electrophoresis from the anode end toward the cathode to degrade PAEs and pharmaceuticals in the sediment if any; (2) an electric potential gradient of 1.5 V cm(-1) would help the removal of PAEs and acetaminophen in the blank test, which no "novel oxidants" was added to the remediation system; (3) the practice of electrode polarity reversal would maintain neutral pH for sediment after remediation; (4) injection of equally divided dose of 10 mL novel oxidant into the anode reservoir and four injection ports on the top of sediment chamber would further enhance the removal efficiency; and (5) an extension of treatment time from 14 d to 28 d is beneficial to the removal efficiency as expected. In comparison, the remediation performance obtained by the EK-assisted nano-SHM/H2O2 oxidation process is superior to that of the batch degradation test, but is comparable with other EK integrated technologies for the treatment of same contaminants. Thus, it is expected that the EK-assisted nano-SHM/H2O2 oxidation process is a viable technology for the removal of phthalate esters and pharmaceuticals from river sediments in large-scale operations.
Center for Emerging Contaminants Research, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan; Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan.
Gordon C C
GCC
Yang
Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan. Electronic address: harm360@gmail.com.
Sheng-Chih
SC
Huang
Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan.
Chih-Lung
CL
Wang
Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan.
Yu-Sheng
YS
Jen
D000082:Acetaminophen / Q000302:isolation & purification; D002384:Catalysis; D052918:Environmental Restoration and Remediation / Q000379:methods*; D004952:Esters / Q000737:chemistry; D019015:Geologic Sediments / Q000032:analysis*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D058085:Iron Compounds / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry; D010795:Phthalic Acids / Q000737:chemistry*; D045483:Rivers / Q000737:chemistry*
D004952:Esters; D058085:Iron Compounds; D016877:Oxidants; D010795:Phthalic Acids; C511969:schwertmannite; D000082:Acetaminophen; C032279:phthalic acid; D006861:Hydrogen Peroxide
Acetaminophen; Electrokinetic process; Phthalate esters; Schwertmannite; Sediment