Formation of hazardous inorganic by-products during electrolysis of seawater as a disinfection process for desalination.
From our previous study, an electrochemical process was determined to be a promising tool for disinfection in a seawater desalination system, but an investigation on the production of several hazardous by-products is still required. In this study, a more intensive exploration of the formation patterns of perchlorate and bromate during the electrolysis of seawater was conducted. In addition, the rejection efficiencies of the targeted by-products by membrane processes (microfiltration and seawater reverse osmosis) were investigated to uncover the concentrations remaining in the final product from a membrane-based seawater desalination system for the production of drinking water. On the electrolysis of seawater, perchlorate did not provoke any problem due to the low concentrations formed, but bromate was produced at a much higher level, resulting in critical limitation in the application of the electrochemical process to the desalination of seawater. Even though the formed bromate was rejected via microfiltration and reverse osmosis during the 1st and 2nd passes, the residual concentration was a few orders of magnitude higher than the USEPA regulation. Consequently, it was concluded that the application of the electrochemical process to seawater desalination cannot be recommended without the control of bromate.
Oh
Byung Soo
BS
Center for Seawater Desalination Plant, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712, Republic of Korea.
Oh
Sang Guen
SG
Hwang
Youn Young
YY
Yu
Hye-Weon
HW
Kang
Joon-Wun
JW
Kim
In S
IS
D001959:Bromates / Q000138:chemical synthesis* / Q000737:chemistry; D002713:Chlorine / Q000032:analysis; D004203:Disinfection; D004572:Electrolysis; D005374:Filtration; D015386:Hazardous Substances / Q000138:chemical synthesis; D010472:Perchlorates / Q000138:chemical synthesis* / Q000737:chemistry; D012623:Seawater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000138:chemical synthesis* / Q000737:chemistry; D018508:Water Purification
D001959:Bromates; D015386:Hazardous Substances; D010472:Perchlorates; D014874:Water Pollutants, Chemical; D002713:Chlorine; C494474:perchlorate