Membranes
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2023
·Vol. 13
·期 4
·443
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IF 4.2
Xinqiang Xu,Hua Zhang,Jiang Jin
A novel approach to evaporate brine wastewater using a ceramic aeration membrane was proposed. A high-porosity ceramic membrane was selected as the aeration membrane and was modified with hydrophobic modifiers to avoid undesired surface wetting. The water contact angle of the ceramic aeration membrane reached 130° after hydrophobic modification. The hydrophobic ceramic aeration membrane showed excellent operational stability (up to 100 h), high salinity (25 wt.%) tolerance, and excellent regeneration performance. The evaporative rate reached 98 kg m−2h−1,which could be restored by ultrasonic cleaning after the membrane fouling occurred. Furthermore, this novel approach shows great promise for practical applications toward a low cost of only 66 kW·h·m−3.Keywords:high-porosity ceramic membrane;hydrophobic modification;brine wastewater;aeration evaporation
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
CHEMOSPHERE
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2024
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IF 8.1
Yizhuo Yang,Zhang Yan,Xin Luo,Jianxin Cao,Wenxiao Zheng,Chunhua Feng
The electrochemical treatment of saline wastewater is prone to the formation of inorganic chlorinated byproducts, being a significant challenge for this technology. In this study, we introduce an electrooxidation system utilizing a self-supporting nitrogen-doped carbon-based cathode embedded in carbon cloth (N@C-CC), designed to generate H₂O₂. This system aims to rapidly neutralize free chlorine produced at the anode, a precursor to inorganic chlorinated byproducts, thereby reducing their formation. Our results demonstrate that using the N@C-CC cathode in saline wastewater treatment yielded considerably lower concentrations of ClO₃⁻ and ClO₄⁻ (0.08 mM and 0.024 mM, respectively), which were only 20.5% and 22.7% of the levels produced using a Pt cathode without H₂O₂ generation. Moreover, the presence of cathodically generated H₂O₂ that quenches free chlorine did not significantly impact the degradation performance of phenol. Electron paramagnetic resonance tests and quenching experiments indicated that 1 O₂ was primarily responsible for phenol removal. Validation with real wastewater demonstrated reductions of 68.6% and 56.3% in ClO 3 − and ClO 4 − concentrations, respectively, while effectively removing other pollutants. This study thus offers a compelling method for mitigating the formation of inorganic chlorinated byproducts during the electrooxidation of saline wastewater.
研究领域:
环境科学
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化学工程
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DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2024
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IF 10.8
Wenxiao Zheng,Xin Luo,Hengyi Fu,Weijian Duan,Shishu Zhu,Xin Yang,Chunhua Feng
The electrochemical technology provides a practical and viable solution to the global water scarcity issue, but it has an inherent challenge of generating toxic halogenated byproducts in treatment of saline wastewater. Our study reveals an unexpected discovery: the presence of a trace amount of Br– not only enhanced the electrochemical oxidation of organic compounds with electron-rich groups but also significantly reduced the formation of halogenated byproducts. For example, in the presence of 20 μM Br–, the oxidation rate of phenol increased from 0.156 to 0.563 min–1, and the concentration of total organic halogen decreased from 59.2 to 8.6 μM. Through probe experiments, direct electron transfer and HO• were ruled out as major contributors; transient absorption spectroscopy (TAS) and computational kinetic models revealed that trace Br– triggers a shift in the dominant reactive species from Cl2•– to Br2•–, which plays a key role in pollutant removal. Both TAS and electron paramagnetic resonance identified signals unique to the phenoxyl and carbon-centered radicals in the Br2•–-dominated system, indicating distinct reaction mechanisms compared to those involving Cl2•–. Kinetic isotope experiments and density functional theory calculations confirmed that the interaction between Br2•– and phenolic pollutants follows a hydrogen atom abstraction pathway, whereas Cl2•– predominantly engages pollutants through radical adduct formation. These insights significantly enhance our understanding of bromine radical-involved oxidation processes and have crucial implications for optimizing electrochemical treatment systems for saline wastewater.
研究领域:
环境科学
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电化学
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水处理技术
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DOI
PubMed
高影响因子
WATER RESEARCH
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2022
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IF 13.4
Lin Hu,Li Shi,Fei Shen,Qiuwen Tong,Xiaoshu Lv,Yiming Li,Zixun Liu,Liang Ao,Xianming Zhang,Guangming Jiang,Li'an Hou
The high salinity and coexistence of scaling ions (Ca 2+ , Mg 2+ , HCO 3 − ) in wastewater challenge the efficacy and durability of palladium (Pd)-mediated electrocatalytic hydrodechlorination (EHDC) reaction for chlorinated organic pollutant detoxification, due to the accompanying Cl − poisoning at Pd sites and scaling on electrode. In a concentrated NaCl solution (5.8 g L − 1 ) with Ca 2+ (80.0 mg L − 1 ), Mg 2+ (30.0 mg L − 1 ) and HCO 3 − (180.0 mg L − 1 ), the EHDC efficiency of Pd towards 2,4-dichlorophenol decreases significantly from 67.8% to 33.1% in 72.0 h of reaction, and the electrode is covered with layers of fluffy aragonite precipitate. Herein we demonstrate the inclusion of a commercial antiscalant 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC) can prevent both scale formation and Cl − poisoning, leading to an efficient and steady EHDC process. A mechanistic study reveals that the unique dual function of PBTC primarily originates from the bearing phosphonate and carboxyl groups. With the large affinity of these groups (especially the phosphonate group) for scaling cations and Pd, the PBTC can chelate and stabilize the scaling cations in water and replace Cl − at Pd surface. It can also release protons, and trigger the formation of more electron-deficient Pd δ+ species via PBTC-Pd binding, leading to an enhanced EHDC. This work provides effective solutions to the scaling/poisoning issues that commonly encountered in real wastewater and paves a solid road for EHDC application in pollution abatement.
研究领域:
环境工程
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化学工程
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水处理
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催化
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废水管理
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2019
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IF 6.669
Fansheng Meng,Weiwei Huang,Dongfang Liu,Yingxin Zhao,Wenli Huang,Zhongfang Lei,Zhenya Zhang
In this study a continuous flow reactor (CFR) was employed to compare the feasibility of bacterial aerobic granular sludge (AGS-CFR) and algal-bacterial granular sludge (ABGS-CFR) for treating 1–4% saline wastewater. High salinity was found to enhance algae growth in ABGS-CFR, which exhibited slightly higher total nitrogen and phosphorus removal efficiencies at 1–3% salinity. ABGS-CFR maintained good granular stability at 1–4% salinity, while AGS-CFR gradually disintegrated at 4% salinity with 39.3% less accumulation of alginate-like exopolysaccharides in the extracellular polymeric substances. Indole-3-acetic acid (IAA) and superoxide dismutase (SOD) analysis suggested that bacteria and algae ( Nitzschia ) in ABGS-CFR formed a good symbiotic relationship under high salinity conditions, achieving rapid algae growth and 2 times lipid production. High salinity was conducive to enriching Halomonas and Nitzschia but unfavorable for Nitrosomonas and Flavobacterium . Results from this study could provide useful information on interactions between bacteria and algae in ABGS-CFR for its future practical application.
研究领域:
环境工程
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废水处理
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微生物学
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生物技术
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DOI
高影响因子
DESALINATION
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2022
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IF 11.211
Long-Fei Ren,Siqi Zhang,Zhongbao Ma,Yangbo Qiu,Diwen Ying,Jinping Jia,Jiahui Shao,Yiliang He
Excessive discharge of saline antibiotics wastewater into aquatic ecosystem is one crucial environmental issue facing the world today. Herein, an eco-friendly nanofiltration (NF) membrane was fabricated based on coordination complexes of tannic acid and ferric ions (TA-Fe) to selectively separate antibiotic and monovalent salt. Optimal membrane with Fe/TA molar ratio of 3/1 and coordination time of 60 s exhibited Zeta potential of −26.0 mV (pH = 7), water contact angle of 45.5 o and pore radius of 0.36 nm. Consequently, TA-Fe@M3-T60 membrane showed high ciprofloxacin/NaCl rejection ratio of ~5.9 and considerable water permeability of 20.6 ± 1.2 LMH. Besides, relatively high rejection rates were obtained for ofloxacin (94.1 ± 2.2 %) and ciprofloxacin (91.9 ± 2.5 %), while rejection rate for trimethoprim was much lower (68.2 ± 4.1 %). Effects of static/dynamic membrane adsorption of antibiotics on subsequent removal performance were investigated for the first time. Rejection rate improvements of 7.4–15.2 % were observed on pristine membrane compared with pre-adsorbed membrane in short-term NF process. Electrostatic shielding experiment and rejection rate prediction further distinguished the contributions of steric hindrance , electrostatic interaction and membrane adsorption on antibiotics removal, especially antibiotics in zwitterionic form at pH = 7. The findings of this work imply that this newly developed NF membrane has great potential for efficient treatment of antibiotics-contaminated wastewater.
研究领域:
环境科学
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水处理
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膜技术
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废水管理
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）