17 results on '"Jiansheng, Li"'
Search Results
2. Enhanced removal for H
- Author
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Junwen, Qi, Guoping, Wei, Xiuyun, Sun, Lianjun, Wang, and Jiansheng, Li
- Abstract
It is of great significance to protect workers from Sulphur compounds in efficient ways during the regular overhaul or emergency management. Efficient adsorbent with low pressure drop is highly desired in protective equipment. In this work, Cu-ordered mesoporous carbon foams (MeCF) were prepared through the sol-gel casting and wet-impregnation process. The obtained carbon foams possessed typical sponge structure with high porosity and copper particles attached on the skeleton. The characterization on morphology, structure and property illustrated that the presence of mesopores could effectively inhibit the growth of copper particle on MeCF. As the representative of Sulphur compounds, H
- Published
- 2020
3. Metal organic framework derived one-dimensional porous Fe/N-doped carbon nanofibers with enhanced catalytic performance
- Author
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Xin Yan, Ming Zhang, Junwen Qi, Li Miaoqing, Hao Zhang, Rui Luo, Saisai Chen, Jiansheng Li, Xiuyun Sun, and Chaohai Wang
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021110 strategic, defence & security studies ,Environmental Engineering ,Materials science ,Carbonization ,Carbon nanofiber ,Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,Polyacrylonitrile ,chemistry.chemical_element ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Pollution ,Catalysis ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Nanofiber ,Environmental Chemistry ,Metal-organic framework ,Waste Management and Disposal ,Carbon ,Pyrolysis ,0105 earth and related environmental sciences - Abstract
The aggregation of metal nanoparticles and collapse of precursor metal organic frameworks (MOFs) structure during the carbonization process largely hamper the catalytic performance of MOFs-derived carbon catalysts. Here, we report hollow and porous one-dimensional Fe/N-doped carbon nanofibers (Fe/NCNFs) for activating peroxymonosulfate (PMS), which was obtained by immobilizing Fe-MIL-101 on polyacrylonitrile (PAN) nanofibers via electrospinning technique followed by pyrolysis. The presence of one-dimensional PAN channel suppresses the agglomeration tendency of metal particles during the carbonisation process of Fe-MIL-101, resulting in a uniform dispersion of nanoparticles and an increase of catalytic active sites. The resultant Fe/NCNFs-9 possesses unique hierarchical architecture, large active surface area, well-dispersed Fe species, and abundant Fe-N active sites. These superiorities contributed to the better catalytic performance of Fe/NCNFs-9 compared with PAN derived carbon (PAN-C-9) and Fe-MIL-101 derived carbon (Fe-C-9). Through a series of inhibitor experiments and electrochemical tests, the radical pathway is dominant on BPA removal with the participation of the non-radical pathway in the multi-sites Fe/NCNFs-9/PMS/BPA system. Surprisingly, this strategy could successfully disperse Fe species and effectively reduce the Fe leaching. This work supplies a novel method to design efficient MOFs-derived carbon catalysts toward micropollutants removal.
- Published
- 2021
4. Nanostructured CoP: An efficient catalyst for degradation of organic pollutants by activating peroxymonosulfate
- Author
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Weiqing Han, Chao Liu, Jing Wang, Xingru Hu, Lianjun Wang, Rui Luo, Jinyou Shen, Xiuyun Sun, and Jiansheng Li
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Environmental Engineering ,Health, Toxicology and Mutagenesis ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Chemical reaction ,Chloride ,law.invention ,Catalysis ,Reaction rate ,chemistry.chemical_compound ,law ,medicine ,Environmental Chemistry ,Phenol ,Phenols ,Electron paramagnetic resonance ,Waste Management and Disposal ,Environmental engineering ,021001 nanoscience & nanotechnology ,Pollution ,0104 chemical sciences ,chemistry ,Chemical engineering ,0210 nano-technology ,medicine.drug - Abstract
A new catalyst system of CoP/peroxymonosulfate (PMS) is presented, which achieved significant improvement in catalytic activity. Nanostructured CoP, obtained by a simple solid-state reaction, exhibited dramatic catalytic activity with 97.2% degradation of orange II of 100ppm within 4min. Moreover, the high efficiency could be reached for other phenolic pollutants, i.e., phenol and 4-chlorophenol. The reaction rate is much higher than the most reported catalysts. Effect of parameters on catalytic activity of the catalyst was studied in detail. Notably, initial pH of the solution had a slight negative effect on the catalytic performance over the pH range 4.07-10.92, suggesting that CoP has the great adaptability of pH. CoP/PMS demonstrated excellent anti-interference performance toward anions (Cl-, NO3-, and HCO3-). In addition, the pathway of degradation of orange II is proposed by analyzing its intermediates. Based on the XPS spectra of CoP, the identification of the reactive species (OH and SO4-) by electron paramagnetic resonance (EPR) analysis and quenching tests, a possible mechanism for activation of PMS by CoP was proposed. Considering the dramatic catalytic activity, a wide range of pH catalyst suited, CoP is believed to provide robust support for the promising industrial application of AOPs.
- Published
- 2017
5. Recycle of Fenton sludge through one-step synthesis of aminated magnetic hydrochar for Pb2+ removal from wastewater
- Author
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Jiansheng Li, Siqi Tong, Dan Chen, Xiuyun Sun, Zhi-Xiang Xu, Xinbai Jiang, and Jinyou Shen
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021110 strategic, defence & security studies ,Environmental Engineering ,Chemistry ,Health, Toxicology and Mutagenesis ,Diffusion ,0211 other engineering and technologies ,One-Step ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Pollution ,Metal ,Hydrothermal carbonization ,Adsorption ,Chemical engineering ,Wastewater ,Homogeneous ,visual_art ,Monolayer ,visual_art.visual_art_medium ,Environmental Chemistry ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
In order to achieve proper disposal of Fenton sludge, a new recycle method for preparing adsorbents based on one-step hydrothermal carbonization synthesis of aminated hydrochar from Fenton sludge (AHFS) was developed. It was found that AHFS prepared at 340 °C for 60 min showed Pb2+ adsorption capacity as high as 359.83 mg g−1. Adsorption kinetics and thermodynamics results indicated that chemical interaction, intra-particle diffusion and monolayer homogeneous surface of AHFS dominated in adsorption process. The contribution proportion of different mechanisms, including cation-exchange (43.15%), acidic groups complexation (28.17%) and amino groups complexation (24.06%) to overall Pb2+ adsorption, demonstrated that complexation of surface functional groups played the dominated role in the adsorption process. Especially, the addition of amino was conducive to the increased adsorption capacity of hydrochar. In addition, according to the regeneration test, the magnetic AHFS exhibited a satisfactory reproducibility and recyclability. These findings illustrated that the synthesis of aminated magnetic hydrochar not only provided an innovative and efficient heavy metal adsorbent to remove Pb2+ from wastewater, but also explored a new method for the resource utilization of Fenton sludge.
- Published
- 2021
6. Low pressure operated ultrafiltration membrane with integration of hollow mesoporous carbon nanospheres for effective removal of micropollutants
- Author
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Gaojie Wan, Jiansheng Li, Linhan Ni, Jia Xie, Andrea I. Schäfer, Zhipeng Liao, Junwen Qi, and Minh Nhat Nguyen
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021110 strategic, defence & security studies ,Environmental Engineering ,Chemistry ,Health, Toxicology and Mutagenesis ,Size-exclusion chromatography ,0211 other engineering and technologies ,Ultrafiltration ,Portable water purification ,02 engineering and technology ,010501 environmental sciences ,Permeation ,01 natural sciences ,Pollution ,law.invention ,Membrane ,Adsorption ,Chemical engineering ,law ,Environmental Chemistry ,Water treatment ,Waste Management and Disposal ,Filtration ,0105 earth and related environmental sciences - Abstract
An effective way to remove micropollutants is desirable for water purification. In this work, a dual-functional ultrafiltration (DFUF) membrane was fabricated by loading hollow mesoporous carbon nanospheres (HMCNs) into the finger-like support layer pores of the polymeric ultrafiltration (UF) membrane. The designed DFUF membrane combines the high selectivity of ultrafiltration that removes macromolecules based on size exclusion mechanism, and excellent adsorption capacity of HMCNs towards micropollutants in water. When tetracycline (TCN) and 17β-Estradiol (E2) were selected as model micropollutants, corresponding 97 % and 94 % removal were achieved at a low pressure less than 0.15 bar and a flux of 50 and 64 L h−1 m-2 (estimated residence time less than 6 s), respectively. Moreover, simultaneous removal of multiple pollutants was demonstrated by filtering a mixture containing TCN and polyethylene glycols (PEG) 600 kDa macromolecules. Over a long filtration period (more than 60 h) that produced 3180 L/m2 of permeate, the TCN concentration reduced from 100 μg/L in the feed to less than 10 μg/L in the permeate. The above results indicate that the DFUF membrane is capable of removing the small molecular and macromolecular pollutants simultaneously at low pressure, and hence offers remarkable potential in water treatment applications.
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- 2020
7. Enhanced removal for H2S by Cu-ordered mesoporous carbon foam
- Author
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Jiansheng Li, Junwen Qi, Guoping Wei, Lianjun Wang, and Xiuyun Sun
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021110 strategic, defence & security studies ,Environmental Engineering ,Materials science ,Health, Toxicology and Mutagenesis ,Carbon nanofoam ,0211 other engineering and technologies ,chemistry.chemical_element ,02 engineering and technology ,Microporous material ,010501 environmental sciences ,01 natural sciences ,Pollution ,Copper ,Adsorption ,chemistry ,Chemical engineering ,Environmental Chemistry ,Dispersion (chemistry) ,Mesoporous material ,Porosity ,Waste Management and Disposal ,Carbon ,0105 earth and related environmental sciences - Abstract
It is of great significance to protect workers from Sulphur compounds in efficient ways during the regular overhaul or emergency management. Efficient adsorbent with low pressure drop is highly desired in protective equipment. In this work, Cu-ordered mesoporous carbon foams (MeCF) were prepared through the sol-gel casting and wet-impregnation process. The obtained carbon foams possessed typical sponge structure with high porosity and copper particles attached on the skeleton. The characterization on morphology, structure and property illustrated that the presence of mesopores could effectively inhibit the growth of copper particle on MeCF. As the representative of Sulphur compounds, H2S was selected to evaluate the protective performance. Porous copper carbon foams with moderate loading rate (3%) of copper species exhibited longest breakthrough time and largest adsorption capacity. Compared with the microporous foams, MeCF-3 displayed promoted protective performance with breakthrough time of 54.7 min and adsorption capacity of 27.8 mg/g. The enhancement on capabilities was attributed to small-sized copper species with high activity and better dispersion on mesoporous structure. These results reveled that MeCF with sponge frameworks, developed mesoporous structure and high dispersion of active species would be a promising candidate for the elimination of H2S in personal protective equipment.
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- 2020
8. In-situ fabrication of nanoarchitectured MOF filter for water purification
- Author
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Jiansheng Li, Jongbeom Na, Yiyuan Yao, Ping Cheng, Xin Yan, Yusuke Yamauchi, and Chaohai Wang
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021110 strategic, defence & security studies ,Environmental Engineering ,Fabrication ,Materials science ,Health, Toxicology and Mutagenesis ,Groundwater remediation ,0211 other engineering and technologies ,Polyacrylonitrile ,Portable water purification ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Pollution ,Catalysis ,law.invention ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,law ,Oxidizing agent ,Environmental Chemistry ,Metal-organic framework ,Waste Management and Disposal ,Filtration ,0105 earth and related environmental sciences - Abstract
Sulfate radical (SO4•−)-based advanced oxidation processes (SR-AOPs) hold great promise for water purification due to their strong oxidizing and high selectivity. Recently, metal-organic frameworks (MOFs) as catalysts for peroxymonosulfate (PMS) activation to generate SO4•− have shown a bright future. However, the intrinsic nature of powder MOF nanocrystals, such as brittleness and poor processability, largely disturb their large-scale applications in practical. Herein, we develop an in situ growth method to prepare MOF filters. ZIF-67 in situ growth on the polyacrylonitrile (PAN) fibers lead to the ZIF-67/PAN composite fibers with high loading (up to 50 wt %). The loading ZIF-67 can retain their morphology and structure, which is comparable with that of pristine ZIF-67 powder. The ZIF-67/PAN filter demonstrates a high efficiency for organic pollutants removal by PMS activation. Furthermore, through the fabrication of filtration device, the dynamic catalysis results show the ZIF-67/PAN filter is a promising material for water purification. This work provides a new method for applying MOFs-based functional materials to practical water remediation and other separation applications.
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- 2020
9. Removal of lead complexes by ferrous phosphate and iron phosphate: Unexpected favorable role of ferrous ions
- Author
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Lianjun Wang, Jiansheng Li, Xiuyun Sun, Weiqing Han, Jinyou Shen, Qiao Li, and Rui Li
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inorganic chemicals ,021110 strategic, defence & security studies ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,02 engineering and technology ,Human decontamination ,010501 environmental sciences ,Phosphate ,01 natural sciences ,Pollution ,Ferrous ,Metal ,chemistry.chemical_compound ,Adsorption ,chemistry ,Wastewater ,visual_art ,visual_art.visual_art_medium ,Environmental Chemistry ,Iron phosphate ,Leaching (metallurgy) ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Nuclear chemistry - Abstract
The high chemical stability of lead complexes in solution precludes most traditional removal methods. Achieving the efficient, cost-effective, and environmentally friendly removal of metal complexes from wastewater is a challenge. In this study, ferrous phosphate and iron phosphate were used to treat wastewater containing EDTA-Pb, and the differences in their removal processes were compared. Both materials enabled efficient removal of the EDTA-Pb complex from 50 mg Pb/L to
- Published
- 2020
10. N-doped Cu-MOFs for efficient electrochemical determination of dopamine and sulfanilamide
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Saisai Chen, Chaohai Wang, Xiuyun Sun, Wuxiang Zhang, Lianjun Wang, Ming Zhang, Jiansheng Li, and Junwen Qi
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Environmental Engineering ,Materials science ,Nitrogen ,Dopamine ,Health, Toxicology and Mutagenesis ,Inorganic chemistry ,Heteroatom ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,Electrochemistry ,01 natural sciences ,Sulfanilamide ,medicine ,Environmental Chemistry ,Waste Management and Disposal ,Metal-Organic Frameworks ,0105 earth and related environmental sciences ,Detection limit ,021110 strategic, defence & security studies ,Polyvinylpyrrolidone ,Doping ,Electrochemical Techniques ,Pollution ,Linear range ,Octahedron ,Dispersion stability ,Copper ,Water Pollutants, Chemical ,medicine.drug - Abstract
Fast and efficient tracking of micropollutants in aquatic environment by developing novel electrode materials is of great significance. Herein, a polyvinylpyrrolidone (PVP) assisted strategy is applied for synthesis of nitrogen doped Cu MOFs (N-Cu-MOF) for micropollutants electrochemical detection. The designed N-Cu-MOFs possess uniform octahedral shape with large surface area (1184 m2 g-1) and an average size of roughly 450 nm, exhibiting the excellent electroanalytical capability for the detection of multipollutants. In the case of dopamine (DA) and sulfonamides (SA) as typical microcontaminants, the designed N-Cu-MOFs exhibited wide linear ranges of 0.50 nM-1.78 mM and low detection limit (LOD, 0.15 nM, S/N = 3) for the determination of DA, as well as a linear range of 0.01-58.3 μM and LOD (0.003 μM, S/N = 3) for monitoring SA. The improved performance is attributed to the heteroatom introduction and good dispersion stability of N-Cu-MOF with PVP-decorated. The good electroanalytical ability of N-Cu-MOF for detection of DA and SA can provide a guide to efficient and rapid monitor other micropollutants and construct novel electrochemical sensors.
- Published
- 2020
11. Electrochemical treatment of flutriafol wastewater using a novel 3D macroporous PbO
- Author
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Siqi, Liu, Tao, Cui, Anlin, Xu, Weiqing, Han, Jiansheng, Li, Xiuyun, Sun, Jinyou, Shen, and Lianjun, Wang
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Titanium ,Oxides ,Electrochemical Techniques ,Triazoles ,Wastewater ,Water Purification ,Lethal Dose 50 ,Biodegradation, Environmental ,Lead ,Animals ,Porosity ,Filtration ,Water Pollutants, Chemical ,Zebrafish - Abstract
In order to break the high operating cost bottleneck of electrochemical treatment of aqueous flutriafol (FTF), an emerging fungicide, a novel three-dimensional ordered macroporous PbO
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- 2017
12. Influence of NaOH concentrations on synthesis of pure-form zeolite A from fly ash using two-stage method
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Jiansheng Li, Chunfeng Wang, Xiuyun Sun, and Lianjun Wang
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Conservation of Natural Resources ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Industrial Waste ,Mineralogy ,Raw material ,Coal Ash ,Industrial waste ,law.invention ,Waste Management ,law ,Sodium Hydroxide ,Environmental Chemistry ,Particle Size ,Crystallization ,Zeolite ,Waste Management and Disposal ,Prima materia ,Chemistry ,Pollution ,Carbon ,Fly ash ,Particle-size distribution ,Zeolites ,Particulate Matter ,Particle size ,Nuclear chemistry - Abstract
Synthesis of pure-form zeolite A were investigated using four concentrations of NaOH solution to dissolve Si source form fly ash, and with the addition of Al source, to prepare initial gel. Experimental results demonstrated, for two-stage method, that NaOH concentrations in initial gel played an important role in synthesis of pure-form zeolite A using fly ash as raw materials. Generally, pure-form zeolite A could be synthesized when following conditions were used: NaOH concentrations, 1.67, 5 and 6.67 M; the synthesis temperature, 100 degrees C; the corresponding crystallization time, 340, 250 and 190 min. However, a mixture phases of zeolites A and X were obtained at the condition of 3.33 M NaOH solution during various crystallization times. It was found that the higher NaOH concentration was used, the shorter crystallization time of zeolite A was required and the narrower particle size distribution of zeolite A was achieved. In addition, zeolite A submicron-crystals were first synthesized from fly ash using two-stage method in our study.
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- 2008
13. Pretreatment of 2,4-dinitroanisole (DNAN) producing wastewater using a combined zero-valent iron (ZVI) reduction and Fenton oxidation process
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Kexiong Fang, Xiuyun Sun, Lin Zhou, Lianjun Wang, Jinyou Shen, Jiansheng Li, Changjin Ou, Jun Chen, and Zongyuan Zhou
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Environmental Engineering ,Time Factors ,Hydraulic retention time ,Health, Toxicology and Mutagenesis ,Iron ,dnaN ,Anisoles ,Wastewater ,Organic compound ,Waste Disposal, Fluid ,Water Purification ,chemistry.chemical_compound ,Bioreactors ,Environmental Chemistry ,Anaerobiosis ,Hydrogen peroxide ,Waste Management and Disposal ,Effluent ,Chromatography, High Pressure Liquid ,chemistry.chemical_classification ,Zerovalent iron ,Chromatography ,Equipment Design ,Hydrogen Peroxide ,Hydrogen-Ion Concentration ,Pollution ,Oxygen ,chemistry ,Biofilms ,Spectrophotometry, Ultraviolet ,Water Pollutants, Chemical ,Nuclear chemistry ,2,4-Dinitroanisole - Abstract
A combined zero-valent iron (ZVI) reduction and Fenton oxidation process was tested for the pretreatment of 2,4-dinitroanisole (DNAN) producing wastewater. Operating conditions were optimized and overall performance of the combined process was evaluated. For ZVI process, almost complete reduction of nitroaromatic compounds was observed at empty bed contact time (EBCT) of 8 h. For Fenton process, the optimal pH, H 2 O 2 to Fe(II) molar ratio, H 2 O 2 dosage and hydraulic retention time (HRT) were found to be 3.0, 15, 0.216 mol/L and 5 h, respectively. After pretreatment by the combined ZVI-Fenton process under the optimal conditions, aromatic organic compound removal was as high as 77.2%, while the majority of COD remained to be further treated by sequent biological process. The combined anaerobic-aerobic process consisted of an anaerobic baffled reactor (ABR) and a moving-bed biofilm reactor (MBBR) was operated for 3 months, fed with ZVI-Fenton effluent. The results revealed that the coupled ZVI-Fenton-ABR-MBBR system was significantly efficient in terms of correcting the effluent's main parameters of relevance, mainly aromatic compounds concentration, COD concentration, color and acute toxicity. These results indicate that the combined ZVI-Fenton process offers bright prospects for the pretreatment of wastewater containing nitroaromatic compounds.
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- 2012
14. Bioelectrochemical system for recalcitrant p-nitrophenol removal
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Yang Mu, Lianjun Wang, Weiqing Han, Jiansheng Li, Yanyan Zhang, Xiuyun Sun, Cencen Feng, Fei Jia, and Jinyou Shen
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Environmental Engineering ,Anaerobic respiration ,Waste management ,Hydraulic retention time ,Health, Toxicology and Mutagenesis ,Inorganic chemistry ,Electrochemistry ,Pollution ,Cathode ,Anode ,law.invention ,Nitrophenols ,Nitrophenol ,chemistry.chemical_compound ,chemistry ,Wastewater ,law ,Environmental Chemistry ,Spectrophotometry, Ultraviolet ,Waste Management and Disposal ,Chromatography, High Pressure Liquid - Abstract
Bioelectrochemical system (BES) for recalcitrant p-nitrophenol (PNP) removal was investigated in this study. Effective removal of PNP at rates up to 9.14 ± 0.48 mol m(-3)d(-1) was achieved at an energy consumption as low as 0.010 ± 0.002 kWh mol(-1) PNP. PNP removal rate was enhanced with negative cathode potential, increased influent PNP concentration and shortened hydraulic retention time (HRT). Although the coulombic efficiencies at the anode did not exceed 40%, coulombic efficiencies for PNP removal at the cathode were above 70% at various cathode potentials. Compared with conventional anaerobic process, the cosubstrate dosage in BES was significantly reduced due to the high coulombic efficiencies at the cathode. p-Aminophenol (PAP) was identified as the dominant product of PNP reduction at the abiotic graphite cathode of BESs. This study demonstrated that the BES had a potential for efficient removal of nitrophenol pollutants from wastewater.
- Published
- 2011
15. Biological denitrification of high-nitrate wastewater in a modified anoxic/oxic-membrane bioreactor (A/O-MBR)
- Author
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Xiuyun Sun, Rui He, Jiansheng Li, Lianjun Wang, Jinyou Shen, and Weiqing Han
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Environmental Engineering ,Denitrification ,Health, Toxicology and Mutagenesis ,Industrial Waste ,Membrane bioreactor ,Water Purification ,chemistry.chemical_compound ,Bioreactors ,Nitrate ,Explosive Agents ,Bioreactor ,Environmental Chemistry ,Water Pollutants ,Nitrite ,Waste Management and Disposal ,Chromatography ,Nitrates ,Membrane reactor ,Chemical oxygen demand ,Hydrogen-Ion Concentration ,Pollution ,Anoxic waters ,Aerobiosis ,Carbon ,Biodegradation, Environmental ,chemistry ,Environmental chemistry - Abstract
A modified anoxic/oxic-membrane bioreactor has been applied to the denitrification of a high strength nitrate waste (about 3600 mg/L nitrate-N) generated from an initiating explosive factory. Nitrate removal efficiency and nitrite accumulation in the treated water were investigated under various conditions set by several factors including the type of carbon source used, ratios of carbon to nitrogen, pH and hydraulic retention times (HRTs). The results of the preliminary experiments, which were carried out in parallel CSTR systems, demonstrated that sodium acetate had shown the best performance as the external carbon source. The optimal reaction parameters in the anoxic/oxic-membrane bioreactor were pH 7.5–8.5, C/N 1.56 and HRT 30 h, with over 99.9% of nitrate removed and without accumulation of nitrite. Explicitly high average-specific denitrification rate of 324 mg NO3−-N/g VSS/h could be attained under these conditions. The aerobic process and membrane module used subsequently could remove the residual COD, excessive biomass and soluble microbial products generated during the denitrification process.
- Published
- 2009
16. Biodegradation kinetics of picric acid by Rhodococcus sp.NJUST16 in batch reactors
- Author
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Yanchun Li, Jianfa Zhang, Weiqing Han, Xiuyun Sun, Yi Zuo, Jiansheng Li, Lianjun Wang, Rui He, and Jinyou Shen
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Environmental Engineering ,Health, Toxicology and Mutagenesis ,Kinetics ,Picric acid ,Water Purification ,chemistry.chemical_compound ,Bioreactors ,Picrates ,Environmental Chemistry ,Rhodococcus ,Phenols ,Microbial biodegradation ,Waste Management and Disposal ,Chromatography ,biology ,Biodegradation ,biology.organism_classification ,Pollution ,Decomposition ,Biodegradation, Environmental ,chemistry ,Yield (chemistry) ,Water Pollutants, Chemical ,Nuclear chemistry - Abstract
Biological degradation of 2,4,6-trinitrophenol (TNP) by Rhodococcus sp.NJUST16 in mineral salt medium was investigated in shake-flask experiments at pH of 7.0 and 30°C, over a wide range of initial TNP concentration (20–800 mg l −1 ). The TNP was observed to be the inhibitory compound. For the studied concentration range, Haldane's model could be fitted to the growth kinetics data well with the kinetic constants μ max = 0.2362 h −1 , K s = 9.9131 mg l −1 and K i = 362.7411 mg l −1 . Further, the variation of observed yield coefficient Y with initial TNP concentration and the decay coefficient were investigated. It is our view that the above information would be useful for modeling and designing the units treating TNP-containing wastewaters.
- Published
- 2008
17. Treatment of bactericide wastewater by combined process chemical coagulation, electrochemical oxidation and membrane bioreactor
- Author
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Lianjun Wang, Jiansheng Li, Weiqing Han, and Xiuyun Sun
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Flocculation ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Membrane bioreactor ,Waste Disposal, Fluid ,Water Purification ,Electrolytes ,Bioreactors ,Bioreactor ,Electrochemistry ,Environmental Chemistry ,Coagulation (water treatment) ,Organic Chemicals ,Waste Management and Disposal ,Chromatography ,Membrane reactor ,Chemistry ,Chemical oxygen demand ,Temperature ,Equipment Design ,Hydrogen-Ion Concentration ,Pollution ,Carbon ,Anti-Bacterial Agents ,Oxygen ,Waste treatment ,Thiazoles ,Wastewater ,Models, Chemical ,Water Pollutants, Chemical ,Nuclear chemistry - Abstract
Bactericide wastewater (BIW) contains isothiazolin-ones, high salinity, toxicity and non-biodegradable organic concentrations. In order to enhance biodegradable capacity, chemical coagulation and electrochemical oxidation were applied to pretreatment processes. FeSO4·7H2O, pH 12 and 20 mmol/l were determined as optimal chemical coagulation condition; and 15 mA/cm2 of current density, 10 ml/min of flow rate and pH 7 were chosen for the most efficient electrochemical oxidation condition at combined treatment. The wastewater which consisted mainly of isothiazolin-ones and sulfide was efficiently treated by chemical coagulation and electrochemical oxidation. The optimal pretreatment processes showed 60.9% of chemical oxygen demand (COD), 99.5% of S2− and 96.0% of isothiazolin-ones removal efficiency. A biological treatment system using membrane bioreactor (MBR) adding powder-activated carbon (PAC) was also investigated. COD of the wastewater which was disposed using a MBR was lower than 100 mg/l.
- Published
- 2007
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