Zhongsen Yan, Xiaolei Chen, Huarong Yu, Fangshu Qu, Dan Qu, Haiqing Chang, Bart Van der Bruggen
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引用次数: 0
Abstract
Although electrooxidation can remove refractory organics, a significant amount of energy is required for non-selective oxidation, and the oxygen evolution reaction (OER) contributes little to the process. In this study, the conventional electrolytic bubbles were enhanced to improve the performance of organic matter removal. Using humic acid as a model recalcitrant organic pollutant, a membrane electrochemical reactor (MER) was designed to separate mixed bubbles (e.g., H₂ and O₂) produced during electrooxidation with a diaphragm, thereby dividing the individual MER O2 and MER H2. The bubbles stability of MER O2 was higher than that of conventional electrooxidation and aeration, which facilitated the removal of humic acid. Surfactants with different electrical characteristics were further used to enhance the interaction between the bubbles and humic acid. After the addition of cetyltrimethylammonium bromide (CTAB 80 mg/L), the positive charge of the MER O2 bubbles intensified, inducing the removal of 92.8% humic acid (250 mg/L) with an oxidation rate <3.7%. Moreover, CTAB could be reused after foam fractionation. Using zeta potential distribution theory, the initial electrical properties of MER O2 (+) and MER H2 (-) were clarified, as well as the charge intensification by CTAB on MER O2 bubbles. Besides, the acidification by MER imparted initial electrical properties to the bubbles and led to the aggregation of humic acid, and the humic acid adhering to the bubbles further isolated the merging of the bubbles. The application of enhanced electrolytic bubbles offers a novel approach to reducing energy consumption in humic acid removal via electrooxidation systems.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.