A ternary composite of TiO2 and a SiO2-Al2O3 aerogel with good photocatalytic activity was prepared by a simple sol-gel method with TiO2 nanoparticles and SiO2-Al2O3 aerogels derived from industrial fly ash.The struct...A ternary composite of TiO2 and a SiO2-Al2O3 aerogel with good photocatalytic activity was prepared by a simple sol-gel method with TiO2 nanoparticles and SiO2-Al2O3 aerogels derived from industrial fly ash.The structural features of the TiO2/SiO2-Al2O3 aerogel composite were investigated by X-ray powder diffraction,Fourier transform infrared spectroscopy,transmission electron microscopy,gas adsorption measurements and diffuse reflectance UV-visible spectroscopy.The optimal conditions for photocatalytic degradation of 2-sec-butyl-4,6-dinitrophenol（DNBP],included an initial DNBP concentration of 0.167 mmol/L at pH = 4.86 with a catalyst concentration of 6 g/L,under visible light irradiation for 5 h.A plausible mechanism is proposed for the photocatalytic degradation of DNBP.Our composite showed higher photocatalytic activity for DNBP degradation than that of pure TiO2.This indicates that this material can serve as an efficient photocatalyst for degradation of hazardous organic pollutants in wastewater.展开更多
Some aromatic compounds, phenol, aniline and nitrobenzene, were oxidized in supercritical water. It was experimentally found that the chemical oxygen demand (COD) removal efficiency of these organic compounds can achi...Some aromatic compounds, phenol, aniline and nitrobenzene, were oxidized in supercritical water. It was experimentally found that the chemical oxygen demand (COD) removal efficiency of these organic compounds can achieve a high level more than 90% in a short residence time at temperatures high enough. As temperature, pressure and residence time increase, the COD removal efficiencies of the organic compounds would all increase. It is also found that temperature and residence time offer greater influences on the oxidation process than pressure. The difficulty in oxidizing these three compounds is in the order of nitrobenzene ＞ aniline ＞ Phenol. In addition, it is extremely difficult to oxidize aniline and nitrobenzene to CO2 and H2O at the temperature lower than 873.15 K and 923.15 K, respectively. Only at the temperature higher than 873.15 K and 923.15 K, respectively, the COD removal efficiencies of 90% of aniline and nitrobenzene can be achieved.展开更多
Catalytic wet air oxidation (CWAO) was investigated in laboratory-scale experiments for the treatment of o-chlorophenol in wastewater. Experimental results showed that wet air oxidation (WAO) process in the absence of...Catalytic wet air oxidation (CWAO) was investigated in laboratory-scale experiments for the treatment of o-chlorophenol in wastewater. Experimental results showed that wet air oxidation (WAO) process in the absence of catalyst was also effective for o-chlorophenol in wastewater treatment. Up to 80% of the initial CODCr was removed by wet air oxidation at 270℃ with twice amount of the required stoichiometric oxygen supply. At temperature of 150℃, the removal rate of CODCr was only 30%. Fe2(SO4)3, CuSO4, Cu(NO3)2 and MnSO4 exhibited high catalytic activity. Higher removal rate of CODCr was obtained by CWAO. More than 96% of the initial CODCr was removed at 270℃ and 84.6%-93.6% of the initial CODCr was removed at 150℃. Mixed catalysts had better catalytic activity for the degradation of o-chlorophenol in wastewater.展开更多
The heterogeneous UV/Fenton process with the appropriate amount of Fe-Mn-Cu-Y as catalyst was developed and various operation conditions for the degradation of phenol were evaluated. The results indicated that by usin...The heterogeneous UV/Fenton process with the appropriate amount of Fe-Mn-Cu-Y as catalyst was developed and various operation conditions for the degradation of phenol were evaluated. The results indicated that by using the het-erogeneous UV/Fenton process, the CODcr removal rate reached almost 100% for wastewater containing phenol. Compared with the homogeneous process, the developed catalyst could be used at wider pH range in the UV/Fenton process. Com-parison of various heterogeneous process showed that heterogeneous UV/Fenton process was best. The heterogeneous UV/Fenton process with Fe-Mn-Cu-Y catalyst is highly efficient in degrading various organic pollutants.展开更多
Strain EDP3 was isolated from an industrial-activated sludge. It belonged to the gamma group of Pro-teobacteria with an identity of 97.0% to Acinetobacter calcoaceticus according to the 16S rRNA gene sequences. It can...Strain EDP3 was isolated from an industrial-activated sludge. It belonged to the gamma group of Pro-teobacteria with an identity of 97.0% to Acinetobacter calcoaceticus according to the 16S rRNA gene sequences. It can tolerate up to 1000mg·L^-1 phenol at room temperature with a much longer lag phase. This indicates that higher phenol concentration has induced some physiological and genotypic changes in the bacterium. The aim of this study is, therefore, to investigate these responses to phenol concentration variations in strain EDP3. Proteome analysis is conducted by means of a two-dimensional polyacrylamide gel electrophoresis （2D PAGE） and matrix-assisted laser desorption ionization time of flight mass spectrometry （MALDI-TOF-MS） was conducted to obtain a deeper insight into the adaptive responses inside the bacterium. Comparative analysis of the proteome profiles of strain EDP3. grown in 400mg·L^-1 and 1000mg·L^-1 phenol allowed us to identify that among all the proteins up-regulated under the higher phenol concentration, oxidative stress proteins were dominant. The synthesis of a heat shock protein, 60000 chaperonin GroEL, was also amplified. In addition, the expression of one membrane protein, adenosine 5＇-triphosphate （ATP）-binding cassette （ABC） type sugar transporter, was found up-regulated. The inhibition of adenosine 5＇-triphosphate （ATP） and RNA/protein synthesis was also observed.展开更多
The effects of feed temperature and pH value on the removal of aqueous phenol wastewater by vacuum membrane distillation process are studied by experiments employing micro porous membranes of poly vinylidene fluoride ...The effects of feed temperature and pH value on the removal of aqueous phenol wastewater by vacuum membrane distillation process are studied by experiments employing micro porous membranes of poly vinylidene fluoride (PVDF) and ploy tetrafluoro ethylene (PTFE) with nominal average pore sizes 0.22 mm and 0.20 mm, respectively. It is found that the optimal feed temperature for PVDF membrane is 50 ℃; and for PTFE membrane, 60 ℃. The pH value of the feed has little influence on the membrane fluxes and ion rejection ratios, while it influenced considerably on the selectivity. Increase of pH value of the feed is conducive to the increase of selectivity. In the same experimental conditions, PTFE membrane shows better separation performance than PVDF membrane does.展开更多
The SET mechanism between chlorine dioxide （ClO2） and phenol was studied by using ab initio method at 4-31G* level. Geometries of the reactants, intermediate and products of the reaction were optimized and the singl...The SET mechanism between chlorine dioxide （ClO2） and phenol was studied by using ab initio method at 4-31G* level. Geometries of the reactants, intermediate and products of the reaction were optimized and the single point energy calculations of the species were performed. The relative structure data of the reactants, intermediate and products are given.The SET mechanism between ClO2and phenol was confirmed by ab initio calculations. The reaction is exothermic about 200 88 kJ/mol.展开更多
Based on the theory of substrate permeation through the cytoplasmic membrane,and considering the effect of initial concentration of substrate,a new kinetic model of phenol degradation process was proposed,Comparing wi...Based on the theory of substrate permeation through the cytoplasmic membrane,and considering the effect of initial concentration of substrate,a new kinetic model of phenol degradation process was proposed,Comparing with the widely used Haldane model,which is greatly dependent on the initial phenol concentration,our model can be used to simulate the phenol degradation process in a wide range of initial phenol concentration by using only one set of model parameters ,Therefore,this new kinetic model has much more potential applications to industrial design and operation.展开更多
Phenol is considered as pollutant due to its toxicity and carcinogenic effect.Thus,variety of innovative methods for separation and recovery of phenolic compounds is developed in order to remove the unwanted phenol fr...Phenol is considered as pollutant due to its toxicity and carcinogenic effect.Thus,variety of innovative methods for separation and recovery of phenolic compounds is developed in order to remove the unwanted phenol from wastewater and obtain valuable phenolic compound.One of potential method is extraction using green based liquid organic solvent.Therefore,the feasibility of using palm oil was investigated.In this research,palm oil based organic phase was used as diluents to treat a simulated wastewater containing 300×10^(-6) of phenol solution using emulsion liquid membrane process(ELM).The stability of water-in-oil(W/O) emulsion on diluent composition and the parameters affecting the phenol removal efficiency and stability of the emulsion;such as emulsification speed,emulsification time,agitation speed,surfactant concentration,pH of external phase,contact time,stripping agent concentration and treat ratio were carried out.The results of ELM study showed that at ratio7 to 3 of palm oil to kerosene,5 min and 1300 r·min^(-1) of emulsification process the stabile primary emulsion were formed.Also,no carrier is needed to facilitate the phenol extraction.In experimental conditions of500 r·min^(-1) of agitation speed,3%Span 80,pH 8 of external phase,5 min of contact time,0.1 mol·L^(-1) NaOH as stripping agent and 1:10 of treat ratio,the ELM process was very promising for removing the phenol from the wastewater.The extraction performance at about 83%of phenol was removed for simulated wastewater and an enrichment of phenol in recovery phase as phenolate compound was around 11 times.展开更多
By measuring the respiratory oxygen consumption, a study on the aerobic biodegradability of 2-fluorophenol, 3- fluorophenol and 4-fluorophenol was conducted using activated sludge acclimated by themselves respectively...By measuring the respiratory oxygen consumption, a study on the aerobic biodegradability of 2-fluorophenol, 3- fluorophenol and 4-fluorophenol was conducted using activated sludge acclimated by themselves respectively. The experimental results showed that bio-oxidation ratios of 2- fluorophenol, 3- fluorophenol and 4- fluorophenol were 25.30%, 35.28% and 36.60% respectively, and the constmdng rate constants were 0.009 3, 0.013 3 and 0.014 5 L/ gSS. h respect/vdy. The aerobic biodegradability of the mono-fluorophenols decreased in the order of 4- fluorop- henol〉3 - fluorophenol 〉2 - fluorophenol, resulting mainly from the different octanol/water partition coefficient and the different steric parameter of the fluorophenols which can affect the penetration of fluorophenol into cell membrane.展开更多
O-nitro-phenol wastewater which contains refractory organic matters can not be degraded by conventional biological methods. In this work, o-nitro-phenol wastewater was effectively treated using magnetization-enhanced ...O-nitro-phenol wastewater which contains refractory organic matters can not be degraded by conventional biological methods. In this work, o-nitro-phenol wastewater was effectively treated using magnetization-enhanced oxidation by NaCIO solutions. The pollutant concentrations in wastewater were 250 mg/L o-nitro-phenol, 2,000 mg/L CODcr and 150 times color. The experimental results show that, using the method in this work, 94.4% o-nitro-phenol, 94.2% CODCr and 100% color can be removed at pH 6, 200 mg charcoal, 8 mL oxidizer, 5 min reaction time in 1000 mL wastewater. The treatment can be enhanced under magnetic field. CODCr and o-nitro-phenol removal can keep unchanged while the reaction time can be reduced to 3 min when the intensity of magnetic field was 60 mT.展开更多
The equilibrium uptake of phenol and lead（II） ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed a...The equilibrium uptake of phenol and lead（II） ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed at 4, 30 ℃, 250 rpm and 6 hrs respectively. Adsorption isotherms were developed for both the single and binary component systems and expressed by ten models for single and four models for binary systems and model parameters were estimated by the non-linear regression method using STATISTICA version-6 and EXCEEL-2007 software. The maximum loading capacity （qm） of the phenol was 66.8234, 60.4823 mg/g and 37.0370, 13.0988 mg/g for lead in single and binary systems respectively. Desorption experiments indicate that the desorption efficiency with 0.1 M NaOH, 0.1 M HCI solution reaches 97.35%, 98% for phenol and lead respectively. There was only 3.58%, 4.93% decrease in removal efficiency for phenol and lead respectively when used regenerated GAC for one cycle.展开更多
基金supported by the National Natural Science Foundation of China(21377018)the Natural Science Foundation of Liaoning Province of China(2013020116)the Fundamental Research Funds for the Central Universities(DUT15ZD240)~~
文摘A ternary composite of TiO2 and a SiO2-Al2O3 aerogel with good photocatalytic activity was prepared by a simple sol-gel method with TiO2 nanoparticles and SiO2-Al2O3 aerogels derived from industrial fly ash.The structural features of the TiO2/SiO2-Al2O3 aerogel composite were investigated by X-ray powder diffraction,Fourier transform infrared spectroscopy,transmission electron microscopy,gas adsorption measurements and diffuse reflectance UV-visible spectroscopy.The optimal conditions for photocatalytic degradation of 2-sec-butyl-4,6-dinitrophenol（DNBP],included an initial DNBP concentration of 0.167 mmol/L at pH = 4.86 with a catalyst concentration of 6 g/L,under visible light irradiation for 5 h.A plausible mechanism is proposed for the photocatalytic degradation of DNBP.Our composite showed higher photocatalytic activity for DNBP degradation than that of pure TiO2.This indicates that this material can serve as an efficient photocatalyst for degradation of hazardous organic pollutants in wastewater.
基金the Research Foundation of SINOPEC(No. X596006) and Cao Guangbiao's Advanced Research Foundation of Zhejiang University.
文摘Some aromatic compounds, phenol, aniline and nitrobenzene, were oxidized in supercritical water. It was experimentally found that the chemical oxygen demand (COD) removal efficiency of these organic compounds can achieve a high level more than 90% in a short residence time at temperatures high enough. As temperature, pressure and residence time increase, the COD removal efficiencies of the organic compounds would all increase. It is also found that temperature and residence time offer greater influences on the oxidation process than pressure. The difficulty in oxidizing these three compounds is in the order of nitrobenzene ＞ aniline ＞ Phenol. In addition, it is extremely difficult to oxidize aniline and nitrobenzene to CO2 and H2O at the temperature lower than 873.15 K and 923.15 K, respectively. Only at the temperature higher than 873.15 K and 923.15 K, respectively, the COD removal efficiencies of 90% of aniline and nitrobenzene can be achieved.
基金Supported by the Returnee Fourndation of China Ministry of Education.
文摘Catalytic wet air oxidation (CWAO) was investigated in laboratory-scale experiments for the treatment of o-chlorophenol in wastewater. Experimental results showed that wet air oxidation (WAO) process in the absence of catalyst was also effective for o-chlorophenol in wastewater treatment. Up to 80% of the initial CODCr was removed by wet air oxidation at 270℃ with twice amount of the required stoichiometric oxygen supply. At temperature of 150℃, the removal rate of CODCr was only 30%. Fe2(SO4)3, CuSO4, Cu(NO3)2 and MnSO4 exhibited high catalytic activity. Higher removal rate of CODCr was obtained by CWAO. More than 96% of the initial CODCr was removed at 270℃ and 84.6%-93.6% of the initial CODCr was removed at 150℃. Mixed catalysts had better catalytic activity for the degradation of o-chlorophenol in wastewater.
基金Project (No. 20176053) supported by the National Natural Science Foundation of China
文摘The heterogeneous UV/Fenton process with the appropriate amount of Fe-Mn-Cu-Y as catalyst was developed and various operation conditions for the degradation of phenol were evaluated. The results indicated that by using the het-erogeneous UV/Fenton process, the CODcr removal rate reached almost 100% for wastewater containing phenol. Compared with the homogeneous process, the developed catalyst could be used at wider pH range in the UV/Fenton process. Com-parison of various heterogeneous process showed that heterogeneous UV/Fenton process was best. The heterogeneous UV/Fenton process with Fe-Mn-Cu-Y catalyst is highly efficient in degrading various organic pollutants.
文摘Strain EDP3 was isolated from an industrial-activated sludge. It belonged to the gamma group of Pro-teobacteria with an identity of 97.0% to Acinetobacter calcoaceticus according to the 16S rRNA gene sequences. It can tolerate up to 1000mg·L^-1 phenol at room temperature with a much longer lag phase. This indicates that higher phenol concentration has induced some physiological and genotypic changes in the bacterium. The aim of this study is, therefore, to investigate these responses to phenol concentration variations in strain EDP3. Proteome analysis is conducted by means of a two-dimensional polyacrylamide gel electrophoresis （2D PAGE） and matrix-assisted laser desorption ionization time of flight mass spectrometry （MALDI-TOF-MS） was conducted to obtain a deeper insight into the adaptive responses inside the bacterium. Comparative analysis of the proteome profiles of strain EDP3. grown in 400mg·L^-1 and 1000mg·L^-1 phenol allowed us to identify that among all the proteins up-regulated under the higher phenol concentration, oxidative stress proteins were dominant. The synthesis of a heat shock protein, 60000 chaperonin GroEL, was also amplified. In addition, the expression of one membrane protein, adenosine 5＇-triphosphate （ATP）-binding cassette （ABC） type sugar transporter, was found up-regulated. The inhibition of adenosine 5＇-triphosphate （ATP） and RNA/protein synthesis was also observed.
文摘The effects of feed temperature and pH value on the removal of aqueous phenol wastewater by vacuum membrane distillation process are studied by experiments employing micro porous membranes of poly vinylidene fluoride (PVDF) and ploy tetrafluoro ethylene (PTFE) with nominal average pore sizes 0.22 mm and 0.20 mm, respectively. It is found that the optimal feed temperature for PVDF membrane is 50 ℃; and for PTFE membrane, 60 ℃. The pH value of the feed has little influence on the membrane fluxes and ion rejection ratios, while it influenced considerably on the selectivity. Increase of pH value of the feed is conducive to the increase of selectivity. In the same experimental conditions, PTFE membrane shows better separation performance than PVDF membrane does.
文摘The SET mechanism between chlorine dioxide （ClO2） and phenol was studied by using ab initio method at 4-31G* level. Geometries of the reactants, intermediate and products of the reaction were optimized and the single point energy calculations of the species were performed. The relative structure data of the reactants, intermediate and products are given.The SET mechanism between ClO2and phenol was confirmed by ab initio calculations. The reaction is exothermic about 200 88 kJ/mol.
基金Supported by China Petroleum & Chemical Corporation (X599011).
文摘Based on the theory of substrate permeation through the cytoplasmic membrane,and considering the effect of initial concentration of substrate,a new kinetic model of phenol degradation process was proposed,Comparing with the widely used Haldane model,which is greatly dependent on the initial phenol concentration,our model can be used to simulate the phenol degradation process in a wide range of initial phenol concentration by using only one set of model parameters ,Therefore,this new kinetic model has much more potential applications to industrial design and operation.
基金Supported by the Ministry of Higher Education(MOHE)Universiti Teknologi Malaysia(RU Research GrantGUP:Q.J130000.2546.12H50)
文摘Phenol is considered as pollutant due to its toxicity and carcinogenic effect.Thus,variety of innovative methods for separation and recovery of phenolic compounds is developed in order to remove the unwanted phenol from wastewater and obtain valuable phenolic compound.One of potential method is extraction using green based liquid organic solvent.Therefore,the feasibility of using palm oil was investigated.In this research,palm oil based organic phase was used as diluents to treat a simulated wastewater containing 300×10^(-6) of phenol solution using emulsion liquid membrane process(ELM).The stability of water-in-oil(W/O) emulsion on diluent composition and the parameters affecting the phenol removal efficiency and stability of the emulsion;such as emulsification speed,emulsification time,agitation speed,surfactant concentration,pH of external phase,contact time,stripping agent concentration and treat ratio were carried out.The results of ELM study showed that at ratio7 to 3 of palm oil to kerosene,5 min and 1300 r·min^(-1) of emulsification process the stabile primary emulsion were formed.Also,no carrier is needed to facilitate the phenol extraction.In experimental conditions of500 r·min^(-1) of agitation speed,3%Span 80,pH 8 of external phase,5 min of contact time,0.1 mol·L^(-1) NaOH as stripping agent and 1:10 of treat ratio,the ELM process was very promising for removing the phenol from the wastewater.The extraction performance at about 83%of phenol was removed for simulated wastewater and an enrichment of phenol in recovery phase as phenolate compound was around 11 times.
基金Supported by State Key Laboratory of Pollution Control and Resource Reuse ( No. PCRRF06007and PCRRYSF06001) and ShanghaiScience and Technology Commission (No.05JC14059and05DZ22330)
文摘By measuring the respiratory oxygen consumption, a study on the aerobic biodegradability of 2-fluorophenol, 3- fluorophenol and 4-fluorophenol was conducted using activated sludge acclimated by themselves respectively. The experimental results showed that bio-oxidation ratios of 2- fluorophenol, 3- fluorophenol and 4- fluorophenol were 25.30%, 35.28% and 36.60% respectively, and the constmdng rate constants were 0.009 3, 0.013 3 and 0.014 5 L/ gSS. h respect/vdy. The aerobic biodegradability of the mono-fluorophenols decreased in the order of 4- fluorop- henol〉3 - fluorophenol 〉2 - fluorophenol, resulting mainly from the different octanol/water partition coefficient and the different steric parameter of the fluorophenols which can affect the penetration of fluorophenol into cell membrane.
文摘O-nitro-phenol wastewater which contains refractory organic matters can not be degraded by conventional biological methods. In this work, o-nitro-phenol wastewater was effectively treated using magnetization-enhanced oxidation by NaCIO solutions. The pollutant concentrations in wastewater were 250 mg/L o-nitro-phenol, 2,000 mg/L CODcr and 150 times color. The experimental results show that, using the method in this work, 94.4% o-nitro-phenol, 94.2% CODCr and 100% color can be removed at pH 6, 200 mg charcoal, 8 mL oxidizer, 5 min reaction time in 1000 mL wastewater. The treatment can be enhanced under magnetic field. CODCr and o-nitro-phenol removal can keep unchanged while the reaction time can be reduced to 3 min when the intensity of magnetic field was 60 mT.
文摘The equilibrium uptake of phenol and lead（II） ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed at 4, 30 ℃, 250 rpm and 6 hrs respectively. Adsorption isotherms were developed for both the single and binary component systems and expressed by ten models for single and four models for binary systems and model parameters were estimated by the non-linear regression method using STATISTICA version-6 and EXCEEL-2007 software. The maximum loading capacity （qm） of the phenol was 66.8234, 60.4823 mg/g and 37.0370, 13.0988 mg/g for lead in single and binary systems respectively. Desorption experiments indicate that the desorption efficiency with 0.1 M NaOH, 0.1 M HCI solution reaches 97.35%, 98% for phenol and lead respectively. There was only 3.58%, 4.93% decrease in removal efficiency for phenol and lead respectively when used regenerated GAC for one cycle.
