SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Ousmanou Njoya,Shengxin Zhao,Xingyu Kong,Jimin Shen,Jing Kang,Binyuan Wang,Zhonglin Chen
The treatment of industrial wastewater containing Cr(VI)–organic compounds is a long-term concern in the field of environment. In order to realize the high-efficient reduction of Cr(VI) and solve the problem of Cr(III) residue in water environment, a novel catalytic chemical reduction/membrane filtration method was developed for the removal of total Cr (TCr) in a system with coexisting Cr(VI) and oxalate (Ox). The effects of the concentrations of Ox, Fe(III), and Al(III), the dosage of NaBH 4 , and sedimentation time on the removal of Cr(VI) containing Ox by NaBH 4 were investigated. Additionally, the simultaneous removal of turbidity and TCr using a microfiltration membrane was investigated, and the reason for the enhanced TCr removal was clarified. The results of ion chromatography (IC), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) suggested that when Cr(VI) and Ox coexist, low concentrations (0.3 mM) of Fe(III) or Al(III) contributed significantly to the high turbidity caused by the formation of suspended solids (SS) following the reduction of Cr(VI) by NaBH 4 . However, almost all the Cr(III) could be removed by a 1-μm microfiltration membrane. The high turbidity system formed by Ox and Cr(III) is unstable, and some Ox will gradually release their binding sites with Cr(III) with the extension of the natural settling time. For 24 h, 53.75% of Ox was involved in the formation of SS, while in the presence of Fe(III) or Al(III), only 11.28% and 6.30% of Ox were involved, respectively. High concentrations of Fe(III) and Al(III) enhanced the reduction of Cr(VI) by NaBH 4 . The removal of TCr was close to 100% after natural sedimentation for 15 min and combined with a microfiltration membrane. This result is caused because Fe(III)–Cr(III) or Al(III)–Cr(III) can form larger SS, which is easily intercepted by the microfiltration membrane. The development of a novel combined method of catalytic chemical reduction and membrane filtration will be beneficial for reducing the retention of TCr in the environment.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2023
·
IF 3.9
Hongyu Liu,Xin Wen,Jun Zhang,Huan Zhang,Junfu Wei
Catalytic oxidation of contaminants by peroxomonosulfate (PMS) was coupled with membrane filtration to realize high-performance removal of dyes. CoFe 2 O 4 (CFO) was enwrapped and cross linked in calcium alginate (CaAlg) to form CFO−CaAlg composite membrane. The introduction of CFO could not only activate PMS, but also enhanced the stability, hydrophilic property and crosslinking degree of the composite membrane. The final removal rate was enhanced greatly benefiting from the synergistic effect of filtration and catalytic degradation. The removal rate increased from 75% (filtration) to 98% by coupling with catalytic degradation. More importantly, purified water could be obtained immediately instead of waiting for purifying the whole feed solution due to the superiority of cross flow filtration . Radicals quenching and electron spin resonance (ESR) analysis experiment confirm that SO 4 · − contributed 25% and 1 O 2 contributed 75% in catalytic degradation. The composite membrane was effective for different type of dyes and could be reused only being backwashed by purified water because the catalyst CoFe 2 O 4 could recover from Co 3+ to Co 2+ by itself during the process. This study opens a new path of rapid water purification and immediate drinking water supply.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2012
·Vol. 177
·期 1
·195-200
·
IF 3.033
Iqbal Jibran,Yin Changhai,Geng Jinpei,Li Xiaoyu,Li Xiuyong,Du Yiping,Liu Bing Xiang
We report on a simple, sensitive and selective method for the spectrophotometric determination of Ni 2+ in water samples. The analyte ions were collected on a membrane filter in the form of their red complex with 1-(2-pyridylazo)-2-naphthol (PAN), and the absorption spectra of the colored membrane filters were acquired. Effects of pH value, sample volume, and amount of PAN were examined in order to optimize sensitivity. The interference by common other ions was eliminated using appropriate masking agents. The absorbance is linearly related to the concentration of Ni 2+ in the ranges from 0.3 to 1.5 μg L −1 , and from 2 to 10 μg L −1 , respectively, the correlation coefficients (R 2 ) being 0.9871 and 0.9954. Under the optimal conditions, the detection limit is 0.1 μg L −1 . The recoveries in case of spiked samples are between 95.0% and 101.5%, and the relative standard deviations range from 2.8% to 4.1%.
Direct ultra-sensitive spectrophotometric determination of Ni 2+ as Ni-PAN complex on membrane filters
研究领域:
分析化学
·
环境科学
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产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2019
·
IF 4.865
Cong Wei,Hengping Wu,Qiaoping Kong,Jingyue Wei,Chunhua Feng,Guanglei Qiu,Chaohai Wei,Fusheng Li
The refractory nature of residual COD in bio-treated coking wastewater (BTCW) creates barriers for its further treatment and reclamation. It is necessary to fractionate the residual COD in BTCW associated with characterization of solution properties. In this paper, a stepwise process composed of membrane filtration , coagulation, adsorption and ozonation was proposed to fractionate residual COD in the BTCW, in which the COD was stepwise reduced to near zero. In addition, the correlation between COD and water quality indexes as well as solution properties were discussed together with a safety assessment of the water quality. Results showed that the residual COD fractionation percentage contributed by suspended solids, colloids, dissolved organics and reductive inorganic substances in the BTCW was 43.7%, 22.1%, 26.2% and 4.9%, respectively. By stepwise fractionating of these substances, the residual COD was reduced from 168.8 to 5.2 mg L −1 , and the UV 254 value decreased from 1.90 to 0.15 cm −1 . In addition, the particle size of the dominant substances contributing to the residual COD was smaller than 450 nm. Among these substances, the hydrophobic fraction accounted for 78.66% (in the term of TOC). Three-dimensional excitation-emission matrix (3D-EEM) analysis showed that hydrophobic neutral substances (HON) were the main fluorescence constituent in the BTCW, which was highly removable by adsorption. The residual COD after adsorption was mainly composed of reductive inorganic substances . Apart from pursuit of high COD removal rates, more emphasis should be given to the removal of toxic COD. Correlations were observed between the residual COD and water quality indicators as well as solution properties, providing a guideline for optimized removal of residual COD in the BTCW. In summary, these results gave a referential information about the nature of residual COD in the BTCW for the selection of advanced treatment technologies and the management of water quality safety.
研究领域:
环境科学
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污水处理
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Li Chen,Rui Cui,Jiangdong Dai,Yi Wang,Jianming Pan
The treatment of radioactive contaminated water is highly valued all over the world nowadays. In this article, an easy-operated strategy with clear principle for the efficient purification of radioactive iodide wastewater was proposed. Silver nanoparticles (Ag NPs) were grown in-situ at the oxygen-containing defect sites on the edge of GO nanosheets, and the nanocomposites were tested for both adsorption and membrane filtration. HRTEM and XRD results confirmed the crystalline structure of Ag and AgI before and after the adsorption. Fast adsorption equilibrium of iodides was observed within 15 min, and theoretical maximum equilibrium capacity was calculated as high as 150.17 mg g −1 . Dead-end filtration performances of this Ag-GO stacked membranes were further studied from the view of avoiding secondary radionuclides pollution caused by the difficult recovery of nano powders. The rejection ratio of iodides kept constant which was higher than 90 % during the first thirty minutes. AgI precipitation adsorption and size sieving of confined GO interlayers by the stacked Ag-GO membranes happened simultaneously. Suitable concentration of NaOH can wash out most of the iodide ions entrapped between the confined GO interlayers, and desorb part of the AgI meanwhile. All these results elucidated the application of these Ag-GO NPs for the fast and efficient adsorption of iodides are the most prominent advantage, and the adsorbents exhibited desired adsorption irreversibility. Ag-GO filtration membranes could help these nano powders get an easy solid–liquid separation step.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Hongwei Ge,Dafan Chen,Mutai Bao,Dan Zhang,Zhenzong Lu,Xiuping Chen,Yiming Li
The unique stability and complexity of oil-in-water (O/W) nanoemulsions originating from various fields of life and production pose significant challenges for their separation. In this work, a novel oil/water separation membrane (MFC/PPy/Ni–Co–P) is constructed by loading polypyrrole (PPy) particles on cellulose (MFC) membranes to provide growth sites for Ni–Co–P alloys, so as to endow the membrane with in situ bubble-generating capability. Under the external electric field, the MFC/PPy/Ni–Co–P membrane is integrated into the electroflotation filtration system as a cathode, and the effective membrane cleaning and demulsification of nanoemulsions can be realized through the micro-aeration environment constructed in situ . The MFC/PPy/Ni–Co–P membrane demonstrates outstanding performance in gravity-driven separation of various oil/water mixtures, with a rejection rate of >99.99 % and a flux of >3000 L∙m −2 ∙h −1 . The interaction energy between oils with different viscosities and membranes is quantified by the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, revealing the dominant role of acid-base interactions in the anti-fouling process. Notably, the integration of MFC/PPy/Ni–Co–P membrane into an electroflotation separation system enables the coalescence and separation of small-sized, highly stable nanoemulsions with separation efficiencies of >99.86 %. This study provides a novel approach for simultaneous and efficient nanoemulsion separation and membrane fouling remediation, showing a great potential in the development of efficient and sustainable oil/water separation technologies.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
WATER ENVIRONMENT RESEARCH
·
2021
·Vol. 93
·期 10
·2298-2307
·
IF 1.946
Tiantian Song,Wanyi Fu,Shaohui Liu,Xihui Zhang
The performance of the integrated process of coagulation and ozonation with ceramic membrane filtration was evaluated for the treatment of shale gas hydraulic fracturing flowback wastewater (HFFW). The removal efficiencies of carbon oxygen demand (COD Cr ), dissolved organic carbon (DOC), petroleum oils, and turbidity in effluent by the combined process were 87.1%, 72.2%, 94.3%, and 99.6%, respectively. Compared with sole membrane filtration, the transmembrane pressure (TMP) of ceramic membrane filtration was reduced by >99% with the integrated process. The coagulation and ozonation can effectively remove the organics with high molecular weights in the cake layer of ceramic membrane. To the best of our knowledge, this work proposed the combined process of coagulation, ozonation, and flat-sheet ceramic membrane filtration for the treatment of HFFW for the first time. The water quality of the effluent met the discharge standard (Comprehensive Wastewater Discharge Standard GB8978-1996). The findings can provide an important technical foundation for the innovation of integrated equipment for HFFW treatment. Practitioner points An integrated process combining coagulation and ozonation with flat-sheet ceramic membrane ultrafiltration for the treatment of shale gas wastewater. The water quality of this integrated process met the discharge standard. Coagulation and ozonation effectively alleviated the membrane fouling related to organics with high molecular weights. A new avenue for on-site treatment of shale gas wastewater and an alternative of the current centralized wastewater management.
研究领域:
环境工程
·
废水处理
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2020
·
IF 7.183
Songxue Wang,Jiayu Tian,Linran Jia,Jialin Jia,Sujie Shan,Qiao Wang,Fuyi Cui
CuO catalyst dispersed in the feed water (CDF) and CuO catalyst immobilized on the ceramic hollow fiber membrane (CIM) for peroxymonosulfate (PMS) activation were developed and employed in the submerged membrane filtration systems for drinking water treatment , respectively. The performance of the CDF and CIM systems was systematically investigated and compared. The result indicated that BPA concentration, PMS dosage and CuO content exerted much less influence on BPA degradation in the CIM system as compared with that in the CDF system. The CIM system exhibited a greater advantage in the performance of BPA degradation and TOC removal when treating a large volume of feed (>300 mL). In addition, the effect of actual water matrix on the two systems was evaluated. The CIM system showed higher resistance to the adverse influence and better anti-fouling performance than the CDF system. The comparative study on the performance of CDF and CIM systems provides meaningful information for developing the process of membrane filtration coupled with PMS oxidation .
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
FOOD CONTROL
·
2019
·
IF 4.248
Ling Jin,Ting Li,Bin Wu,Tan Yang,Dengchao Zou,Xuehua Liang,Liwen Hu,Ganhui Huang,Jinsheng Zhang
Establishing an efficient and rapid detection method to monitor and control Salmonella is of great significance for ensuring food safety. Here we prepared a new time domain nuclear magnetic resonance (TD-NMR) biosensor based on superparamagnetic nanoparticle (SMN) with ultrasmall particle size and applied it for the detection of Salmonella in milk samples by TD-NMR. The free biotinylated antibody specifically binds to the Salmonella in the homogeneous system through the antigen-antibody interaction, and the biotinylated antibody- Salmonella is captured by streptomycin on the SA-modified SMN by specific binding to biotin. The probes that are attached to the Salmonella separated by membrane filtration for last NMR transverse magnetization time (T 2 ) signal detection. The whole process can accurately detect Salmonella at levels as low as 10 4 cfu mL −1 in less than 2 h. This method holds promise as a powerful analytical tool that enables rapid, nondestructive testing and reconfigurable target bacteria detection.
研究领域:
食品安全
·
生物传感
·
微生物检测
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Da-Qi Cao,Xin Song,Xiao-Min Fang,Wen-Yu Yang,Xiao-Di Hao,Eiji Iritani,Nobuyuki Katagiri
Excess sludge production by wastewater treatment plants (WWTPs) represents a serious environmental problem that necessitates the development of effective sludge treatment/disposal methods. Excess sludge contains valuable materials such as extracellular polymer substances (EPSs), and their recovery is of great practical importance. However, conventional recovery methods afford EPS solutions with moisture contents of ∼100% and the dehydration of these solutions via direct drying methods is considerably energy consuming. Here, we investigate the separation of EPSs extracted from excess sludge by microfiltration (0.5 μm) and ultrafiltration (10 kDa), revealing that Ca 2+ addition reduces the extent of membrane fouling during EPS isolation since the interactions between Ca 2+ and EPS carboxylate groups increase the size and reduce the concentration of colloids/polymers in EPS suspensions. Additionally, we establish an ultrafiltration-based EPS separation protocol, demonstrating that it allows highly efficient EPS recovery (>90%) irrespective of the Ca 2+ concentration, and show that EPSs extracted from excess sludge samples derived from two different WWTPs exhibit similar filtration resistances at Ca 2+ concentrations of 0–4 mM. Finally, we demonstrate that the EPSs recovered from excess sludge can be used as adsorbents for the removal of diverse heavy metal ions (Pb 2+ , Cd 2+ , Cu 2+ ) from wastewater, exhibiting performances that are on par with those of commercial adsorbents and are unaffected by the employed extraction procedure. Based on the obtained results, Ca 2+ addition is confirmed to be a viable method for reducing filtration resistance during the membrane recovery of EPSs, since this ion does not affect the adsorption capacity for heavy metal ions.
研究领域:
环境科学
·
生物技术
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Yuanyuan Hui,Xin Feng,Haoliang Wang,Zai-Sha Mao,Chao Yang
Membrane fouling is a troublesome factor in the design and scale-up of stirred membrane reactors. Many efforts have been made to study the fouling mechanism in traditional membrane filtration. However, it is still ambiguous in stirred membrane reactors (SMRs). For this purpose, we investigated the effects of hydrodynamics on membrane filtration performance in SMRs under constant-pressure operation by combining experiment and computational fluid dynamics (CFD) simulation. The results indicate that the strong axial flow is beneficial in maintaining the stability of membrane permeation, while the strong radial flow works oppositely. In addition, the formation of the filtration cake increases the total membrane filtration resistance but keeps smaller particles from blocking the membrane surface channels, which leads to filtration resistance multiplying rapidly. Hence, the formation of the thick cake, strong axial flow, and weak radial flow is conducive to maintaining permeation flux in order to reduce the replacement of the membrane and improve the period of continuous production.
研究领域:
化学工程
·
环境工程
·
生物工程
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Sharafat Ali,Izaz Ali Shah,Aziz Ahmad,Javed Nawab,Haiou Huang
In this study, pristine multi-walled carbon nanotubes (MWCNTs) were functionalized by using Ar/O 2 plasma treatment technique, which enhanced adsorptive membrane filtration of zinc ions from water and wastewater. The XPS analysis showed that plasma treatment largely increased the surface oxygen groups content of MWCNTs from 2.78% to 6.79%. This change increased the surface negative charged, dispersion and adsorption properties of MWCNTs without causing any damages to the integrity of the nanotube pattern. Pressure-driven filtration of plasma-treated MWCNT (P-CNT) dispersion formed a stable layer inside the lumen of a hollow fiber membrane. The contact angle analysis demonstrated that after incorporation of P-CNT into the HF membrane increased membrane hydrophilicity. The P-CNT membrane effectively removed almost 100% of zinc from synthetic waters and approximately 80% of zinc from a wastewater effluent by surface complexation reaction. A follow-up regeneration study demonstrated that the adsorptive removal of zinc by the CNT membrane was reversible under selected conditions, thus making it possible to repeatedly use the membrane for long-term zinc filtration. This study suggests that HF membranes modified with P-CNTs possess superb adsorption properties for metal ions , allowing the operation of CNT membranes for water treatment .
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）