Coupling UV-H2O2 to accelerate dimethyl phthalate (DMP) biodegradation and oxidation.
Dimethyl phthalate (DMP), an important industrial raw material, is an endocrine disruptor of concern for human and environmental health. DMP exhibits slow biodegradation, and its coupled treatment by means of advanced oxidation may enhance its biotransformation and mineralization. We evaluated two ways of coupling UV-H2O2 advanced oxidation to biodegradation: sequential coupling and intimate coupling in an internal circulation baffled biofilm reactor (ICBBR). During sequential coupling, UV-H2O2 pretreatment generated carboxylic acids that depressed the pH, and subsequent biodegradation generated phthalic acid; both factors inhibited DMP biodegradation. During intimately coupled UV-H2O2 with biodegradation, carboxylic acids and phthalic acid (PA) did not accumulate, and the biodegradation rate was 13 % faster than with biodegradation alone and 78 % faster than with biodegradation after UV-H2O2 pretreatment. Similarly, DMP oxidation with intimate coupling increased by 5 and 39 %, respectively, compared with biodegradation alone and sequential coupling. The enhancement effects during intimate coupling can be attributed to the rapid catabolism of carboxylic acids, which generated intracellular electron carriers that directly accelerated di-oxygenation of PA and relieved the inhibition effect of PA and low pH. Thus, intimate coupling optimized the impacts of energy input from UV irradiation used together with biodegradation.
Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, People's Republic of China.
Bin
B
Chen
Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, People's Republic of China.
Jiaxiu
J
Song
Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, People's Republic of China.
Lihui
L
Yang
Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, People's Republic of China.
Qi
Q
Bai
Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, People's Republic of China.
Rongjie
R
Li
Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, People's Republic of China. zhym@shnu.edu.cn.
Yongming
Y
Zhang
Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, Tempe, AZ, 85287-5701, USA.
Bruce E
BE
Rittmann
D001419:Bacteria / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D001673:Biodegradation, Environmental / Q000187:drug effects / Q000528:radiation effects; D001711:Biotransformation; D052244:Endocrine Disruptors / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D010084:Oxidation-Reduction / Q000187:drug effects / Q000528:radiation effects; D010795:Phthalic Acids / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology; D014466:Ultraviolet Rays
D052244:Endocrine Disruptors; D010795:Phthalic Acids; D012722:Sewage; C024629:dimethyl phthalate; D006861:Hydrogen Peroxide
Di-oxygenation; Dimethyl phthalate; Intimate coupling; UV–H2O2