WATER RESEARCH
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2022
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IF 13.4
Junjie Yu,Hui Xu,Dongsheng Wang,Hongyan Sun,Ruyuan Jiao,Yang Liu,Zhiyuan Jin,Shuo Zhang
Most studies on the interaction between coagulation and NOM (natural organic matter) currently focus on pollutant removal and coagulant species distribution, while studies on floc aging are lacking. Investigation onto the effects of floc aging could guide further processes that utilize flocs, such as densadeg sludge recirculation, floc predeposition for ultrafiltration, sludge condensation, and other traditional sludge reflux processes. In this study, flocs generated by Al 13 and AlCl 3 in microparticle- and nanoparticle-containing water were investigated, and the effect of floc aging on NOM was quantified based on several organic matter characterization techniques. Flocs absorb and release organics during aging. The flocs generated from micro-SiO 2 have a significant absorbing effect for LWM-N (low-molecular-weight neutral substances) and protein-like substances, while the absorption of NOM by flocs generated from nano-SiO 2 is insignificant. HS (humic substances) with high aromaticity are released during floc aging. From the molecular perspective, the molecules released during floc aging are those with higher double bond equivalents and higher aromaticity, while the absorbed molecules are those with lower double bond equivalents and lower aromaticity. 2D-COS (two-dimensional correlation spectroscopy) demonstrated that the flocs generated by Al 13 and AlCl 3 had the same organic release patterns but different intensities, while the flocs generated in the micro-SiO 2 and nano-SiO 2 systems had different organics release patterns. Abundant aluminum hydrolysates with low polymerization and amorphous Al(OH) 3 would be produced from AlCl 3 during the coagulation process and then undergo hydroxyl‑bridging reaction and crystallization during floc aging, thus releasing more HS with high aromaticity into the supernatant; in comparison, prehydrolyzed Al 13 produces a more stable floc and releases less HS during aging. The flocs produced by nano-SiO 2 and Al-based coagulants release higher aromaticity HS into the water than those produced by micro-SiO 2 , which may be related to the formation of more highly polymerized degree hydrolysates and nanocrystalline Al(OH) 3 in the nano-SiO 2 system. The flocs generated in water with micro-SiO 2 may contain a large amount of Al-OH and have a loose structure, thus further absorbing NOM, such as protein-like substances and LWM-N. In contrast, the flocs generated from nano-SiO 2 possess abundant adsorbed water and a denser structure; thus, organic matter cannot be absorbed stably.
研究领域:
环境科学
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水处理工程
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DOI
PubMed
高影响因子
Membranes
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2022
·Vol. 12
·期 9
·887
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IF 4.562
Zhihai He,Kunpeng Wang,Yanling Liu,Ting Zhang,Xiaomao Wang
Loose nanofiltration (LNF) membranes with a molecular weight cut-off (MWCO) of about 1000 Da and high surface negative charge density have great application potential for drinking water treatment pursuing high rejection selectivity between natural organic matter (NOM) and mineral salts. This study was conducted to exploit the novel method coupling non-solvent induced phase separation (NIPS) and interfacial polymerization (IP) for the preparation of high-performance LNF membranes. A number of LNF membranes were synthesized by varying the polyethersulfone (PES) and piperazine (PIP) concentrations in the cast solution for the PES support layer preparation. Results showed that these two conditions could greatly affect the membrane water permeance, MWCO and surface charge. One LNF membrane, with a water permeance as high as 23.0 ± 1.8 L/m2/h/bar, when used for the filtration of conventional process-treated natural water, demonstrated a rejection of NOM higher than 70% and a low rejection of mineral salts at about 20%. Both the mineral salts/NOM selectivity and permselectivity were superior to the currently available LNF membranes as far as the authors know. This study demonstrated the great advantage of the NIPS–IP method for the fabrication of LNF membranes, particularly for the advanced treatment of drinking water.Keywords:loose nanofiltration (LNF);non-solvent induced phase separation (NIPS);interfacial polymerization (IP);water treatment;natural organic matter (NOM);rejection selectivity
研究领域:
环境工程
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膜科学
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水处理技术
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Shaoqian Liu,Chao Lu,Jiemei Liu,Dongxuan Yang,Yanfen Fang,Chun Hu,Lai Lyu
Livestock and poultry manure (LM) management issues stemming from high-density livestock production and the increasing presence of emerging contaminants (ECs) in the water environment pose a significant threat to the ecosystem and public health. It is difficult for current technology to achieve efficient management of LM and ECs with low energy consumption. In this work, a novel and efficient DRC catalyst (Cu-CPM) is prepared for the first time using pigeon manure waste. Cu-CPM facilitates directed electron transfer and energy supply of ECs to activate dissolved oxygen in water as the primary electron acceptor for the generation of reactive oxygen species, resulting in the high-efficiency removal of ECs without the addition of extra oxidants or energy. The performance of the system is unaffected by the presence of various environmental factors (pH, anions, NOM, etc.). Notably, tetracycline (TC) as a typical ECs is completely removed within 15 min in actual water environment. Even after 1,080 h of simulated tertiary wastewater treatment, the removal of TC remains at 100 %. This work provides a reference for resource utilization of LM and efficient removal of ECs in complex water environment without external consumption.
研究领域:
环境科学
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水资源管理
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催化材料科学
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DOI
高影响因子
Journal of Water Process Engineering
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2025
·
IF 6.7
Liping Qiu,Fanduo Meng,Qi Qiu,Xinwei Kang,Shuai Gong,Fengxia Zhang,Jingtao Xu,Feihong Wang,Daoji Wu,Xuewu Zhu
Membrane fouling represents a substantial barrier to the progress of ultrafiltration membranes. The catalytic membrane integrates ultrafiltration with advanced oxidation processes; this provides an efficient solution to mitigate membrane fouling. In this study, CoFe 2 O 4 nanoparticles were integrated into polyvinylidene fluoride (PVDF) to develop a novel composite ultrafiltration membrane (PVDF@CoFe 2 O 4 ). The chemical composition, surface morphology, filtration performance, and catalytic ability of the synthesized PVDF@CoFe 2 O 4 membranes were systematically assessed. The hydrophilicity of the PVDF@CoFe 2 O 4 membrane was enhanced, and its water flux increased by up to 1.4 times using CoFe 2 O 4 doping. The PVDF@CoFe 2 O 4 membrane demonstrated the lowest degree of irreversible fouling and superior stability. In the presence of peroxomonosulfate (PMS), the 2.5 wt% PVDF@CoFe 2 O 4 membrane achieved a norfloxacin (NOR) removal efficiency of 82.5 % within 120 min; this value significantly exceeded the 17.82 % efficiency recorded for the pristine PVDF membrane. The synergistic effect of SO₄ •- and •OH led to the conversion of natural organic matter (NOM) into smaller molecules following oxidation, thereby enhancing the antifouling performance of the membrane. These findings provide a promising approach for mitigating NOM-induced membrane fouling in natural surface water.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ENVIRONMENTAL POLLUTION
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2020
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IF 6.793
Xitong Huang,Yong Li,Ke Chen,Haiyan Chen,Fei Wang,Xiaomin Han,Beihai Zhou,Huilun Chen,Rongfang Yuan
Natural organic matter (NOM) affects the environmental behaviors of AgNPs, which may change their phytotoxicity to plants. However, more evidence can be provided to illustrate how NOM influences AgNPs-induced phytotoxicity. In this study, using rice ( Oryza sativa ) as a model, the effects of NOM, Suwannee River humic acid (SRHA) and fulvic acid (FA), on the dissolution and phytotoxicity of AgNPs were investigated. Silver ions decreased in both AgNPs and AgNO 3 solution in the presence of NOM, and the effect of SRHA was stronger than FA. Image-XRF (iXRF) results showed that Ag mainly remained in the root rather than the shoot of rice seedling exposed to AgNPs. NOM mitigated the negative effects of AgNPs and AgNO 3 on rice with lower germination inhibition rate, less chlorophyll reduction, more relative biomass and less O 2 •− content. Moreover, NOM improved root cell viability according to FDA fluorescent dye as well as maintained the normal root morphology. Interestingly, the neutral sugars content from pectin, hemicellulose 1, hemicellulose 2 and cellulose of root cell wall in AgNPs and AgNO 3 treatments differed from the control, while it was close to the regular content in AgNPs/AgNO 3 +SRHA/FA groups, which implied that NOM regulated the changes. Besides, SRHA led to less germination and less relative biomass than FA due to different chemical characters. Thus, NOM needs to be considered when studying the phytotoxicity of AgNPs.
研究领域:
环境科学
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植物生理学
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农业
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DOI
PubMed
高影响因子
Journal of Environmental Sciences
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2022
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IF 6.796
Zhenxing Yao,Mingquan Wang,Ruibao Jia,Qinghua Zhao,Li Liu,Shaohua Sun
This study examined the effectiveness for degradation of hydrophobic (HPO), transphilic (TPI) and hydrophilic (HPI) fractions of natural organic matter (NOM) during UV/H 2 O 2 , UV/TiO 2 and UV/K 2 S 2 O 8 (UV/PS) advanced oxidation processes (AOPs). The changing characteristics of NOM were evaluated by dissolved organic carbon (DOC), the specific UV absorbance (SUVA), trihalomethanes formation potential (THMFP), organic halogen adsorbable on activated carbon formation potential (AOXFP) and parallel factor analysis of excitation–emission matrices (PARAFAC-EEMs). In the three UV-based AOPs, HPI fraction with low molecular weight and aromaticity was more likely to degradate than HPO and TPI, and the removal efficiency of SUVA for HPO was much higher than TPI and HPI fraction. In terms of the specific THMFP of HPO, TPI and HPI, a reduction was achieved in the UV/H 2 O 2 process, and the higest removal rate even reached to 83%. UV/TiO 2 and UV/PS processes can only decrease the specific THMFP of HPI. The specific AOXFP of HPO, TPI and HPI fractions were all able to be degraded by the three UV-based AOPs, and HPO content is more susceptible to decompose than TPI and HPI content. UV/H 2 O 2 was found to be the most effective treatment for the removal of THMFP and AOXFP under given conditions. C1 (microbial or marine derived humic-like substances), C2 (terrestrially derived humic-like substances) and C3 (tryptophan-like proteins) fluorescent components of HPO fraction were fairly labile across the UV-based AOPs treatment. C3 of each fraction of NOM was the most resistant to degrade upon the UV-based AOPs. Results from this study may provide the prediction about the consequence of UV-based AOPs for the degradation of different fractions of NOM with varied characteristics.
研究领域:
环境科学
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水处理工程
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DOI
PubMed
高影响因子
Journal of Environmental Sciences
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2020
·
IF 4.302
Biao Yang,Hua Fang,Bingqi Chen,Shun Yang,Zhichao Ye,Jianghua Yu
Chlorine dioxide (ClO 2 ) disinfection usually does not produce halogenated disinfection by-products, but the formation of the inorganic by-product chlorite (ClO 2 – ) is a serious consideration. In this study, the ClO 2 – formation rule in the ClO 2 disinfection of drinking water was investigated in the presence of three representative reductive inorganics and four natural organic matters (NOMs), respectively. Fe 2+ and S 2– mainly reduced ClO 2 to ClO 2 – at low concentrations. When ClO 2 was consumed, the ClO 2 – would be further reduced by Fe 2+ and S 2– , leading to the decrease of ClO 2 – . The reaction efficiency of Mn 2+ with ClO 2 was lower than that of Fe 2+ and S 2– . It might be the case that MnO 2 generated by the reaction between Mn 2+ and ClO 2 had adsorption and catalytic oxidation on Mn 2+ . However, Mn 2+ would not reduce ClO 2 – . Among the four NOMs, humic acid and fulvic acid reacted with ClO 2 actively, followed by bovine serum albumin, while sodium alginate had almost no reaction with ClO 2 . The maximum ClO 2 – yields of reductive inorganics (70%) was higher than that of NOM (around 60%). The lower the concentration of reductive substances, the more ClO 2 – could be produced by per unit concentration of reductive substances. The results of the actual water samples showed that both reductive inorganics and NOM played an important role in the formation of ClO 2 – in disinfection.
研究领域:
环境科学
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水处理
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DOI
高影响因子
CHEMOSPHERE
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2018
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IF 4.427
Zongping Wang,Ying Wan,Pengchao Xie,Aijiao Zhou,Jiaqi Ding,Jingwen Wang,Li Zhang,Songlin Wang,Tian C. Zhang
The effects of ultraviolet/persulfate (UV/PS) pretreatment on ultrafiltration (UF) membrane fouling caused by typical natural organic matter (NOM) fractions including humic acid (HA), sodium alginate (SA), and bovine serum albumin (BSA) were investigated. UF membrane fouling during the filtration of different NOM fractions after UV/PS pretreatment was compared through the evaluation of normalized membrane flux decline and membrane fouling reversibility. The fouling mitigation mechanisms were investigated through the characterization of ultraviolet absorbance (UV 254 ), dissolved organic matter , zeta potential , particle size distribution , fluorescence excitation-emission matrix spectra, and fitness of four classic fouling models. Furthermore, the fouled membranes were characterized by Fourier-transform infrared spectroscopy and scanning electron microscopy. The results showed that UV/PS pretreatment significantly alleviated membrane fouling caused by HA, SA, and HA-SA-BSA mixture, and the fouling control performance improved at high PS doses. However, either UV alone or UV/PS pretreatment at low PS dose (10 mg/L) significantly aggravated BSA fouling with the normalized flux at the end of first filtration cycle being 8% and 15%, respectively. The increased particle size of BSA after UV/PS pretreatment was attributed to the formation of aggregates, which mainly accumulated in membrane pores and aggravated membrane fouling. Modeling results suggest that the mitigation of membrane fouling derived from SA and mixed organic fractions was primarily ascribed to the control of cake filtration, while the mitigation of HA fouling was attributed to the declined contribution of standard blocking.
研究领域:
环境科学
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水处理工程
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膜技术
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DOI
PubMed
高影响因子
DESALINATION
·
2022
·
IF 11.211
Cunxian Lai,Xuewu Zhu,Jinyu Li,Weiwei Zhou,Jingtao Xu,Junwen Ding,Jialin Song,Daoji Wu,Heng Liang,Xiaoxiang Cheng
Highly permeable nanofiltration (NF) membranes with efficient natural organic matter (NOM) removal yet preserving essential minerals are of great significance for purifying ground water. In this work, a novel pH-regulated interfacial polymerization (PRIP) strategy was proposed to fabricate ultra-low pressure NF membranes. This strategy was achieved by changing the aqueous solution pH (5, 7, 9, and 11) during IP process. The effects of pH-regulated processes on the structure, chargeability, and physicochemical properties of NF membranes were systematically investigated. Tailored NF membranes under acidic conditions (TFC-pH 5) achieved the ultrahigh permeability of 42.9 L m −2 h −1 bar −1 and 83.3 % moderate rejection of Na 2 SO 4 . For the NF membranes prepared under alkaline conditions (TFC-pH 11), the sieving capacity was obviously improved with fewer defects, and 99.4 % rejection of Na 2 SO 4 was observed. In addition, the purification performance of NF membranes in ground water treatment was further studied. Modified NF membranes showed significant removal of NOM and retain moderate amounts of mineral salts. Finally, the mechanism of the pH-regulated influence on the polyamide active layer formation process was proposed. This study provides a feasible and facile design idea for ultralow-pressure NF membranes in purifying ground water.
研究领域:
环境科学
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材料科学
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水处理
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Yimu Qiao,Xue Han,Feiyong Chen,Cuizhen Sun,Linxu Xu,Rupeng Liu,Xue Shen
To guide the practical application of ozonation and adsorption coupled with ceramic membrane technology , the mitigation mechanisms of O 3 pre-oxidation, powdered activated carbon (PAC) pre-adsorption, and combined O 3 -PAC pretreatment on membrane fouling caused by natural organic matter (NOM) were investigated. The membrane and water quality were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), three-dimensional fluorescence-parallel factor analysis (PARAFAC-EEM), dissolved organic carbon (DOC), laser particle size and Zeta potential . Results showed that the membrane flux decline caused by humic acid (HA), sodium alginate (SA), bovine serum albumin (BSA) and surface water were alleviated by 35.2%, 55.2%, 31.0% and 59.0% after O 3 -PAC pretreatment. Meanwhile the removal rates of HA, SA and BSA were 26.2, 74.8% and 42.3%, respectively. The combination of PAC and O 3 can effectively control the membrane fouling caused by HA and SA. Ozonation can degrade organic matter into small molecules, and PAC has high adsorption to these small molecules, by recycling PAC can take away this part of organic matter, thereby reducing membrane fouling. O 3 showed no obvious advantage for membrane fouling caused by BSA, and the decrease of membrane fouling was mainly attributed to the adsorption of PAC. This investigation highlights the potential mechanism of O 3 -PAC in alleviating the membrane fouling caused by different organic compounds, contributing to the efficient and low-carbon operation of the production.
研究领域:
环境工程
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水处理
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膜技术
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2025
·
IF 9.8
Liping Qiu,Shuai Gong,Qi Qiu,Xuewu Zhu,Daliang Xu,Xinwei Kang,Daoji Wu,Feihong Wang,Zhe Yang,Xiaoxiang Cheng
The elimination of natural organic matter (NOM) and organic micropollutants, while effectively preserving essential dietary minerals, constitutes a crucial objective during nanofiltration (NF) of healthy drinking water production. In this study, sodium citrate (SC), distinguished by its unique functional group, was selected as an aqueous phase additive to customize interfacial polymerization for multifunctional NF membranes. The resultant NF membranes exhibited optimal pore sizes, enhanced negative charge density, increased hydrophilicity, and improved separation selectivity. The optimized NF membrane (PIP-SC6) demonstrated a water permeance of 27.8 LMH bar −1 and achieved over 80 % NOM removal while maintaining calcium and magnesium retention below 10 %. Impressively, PIP-SC6 displayed >76.9 % rejection for four selected organic micropollutants while achieving double the permeance compared to commercial NF270. The effluent produced showed low levels of organic matter content while retaining beneficial mineral elements suitable for healthy drinking water consumption. Furthermore, PIP-SC6 exhibited double resistance to both organic fouling and gypsum fouling compared to NF270. This research offers a new approach to customizing highly selective NF membranes aimed at producing healthy drinking water.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2023
·
IF 7
Yuying Hu,Xin Wang,Xiaohuan Zheng,Kangqi Jiang,Hao Deng,Xiaoming Peng,Hongling Dai,Yang Wei,Fengping Hu
Natural organic matter (NOM) widely exists in natural water bodies and threat drinking water safety. This study aims to construct an integrated photocatalytic/coagulation system and explore its treatment efficiency for NOM in source water. Morphological characteristics of the floc complex were studied based on the machine vision detection system. In addition, structural change characteristics of the floc complex in the integrated photocatalytic/coagulation system were revealed from microscopic perspective to clarify the mechanism of its effect in source water treatment process. And recycling and recycling method of photocatalyst was optimized. The results showed that the integrated photocatalytic/coagulation system can effectively reduce generation of DBPs at concentration level of μg·L −1 , and the formed petal-like BiFeO 3 -core floc complex can achieve rapid sedimentation and had excellent recycling performance. The construction of integrated photocatalytic/coagulation system in this study is expected to provide a theoretical basis for achieving low consumption and high efficiency improvement of source water quality.
研究领域:
环境科学
·
水处理工程
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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）