探究了抗氧化剂的种类、抗氧化剂2,6-二叔丁基-4-甲基苯酚(BHT)的用量及其添加方式对乙烯-醋酸乙烯共聚物(EVA )/线型低密度聚乙烯(LLDPE)硅烷交联材料的接枝率、吸光比( R )、耐热性能和力学性能的影响。结果表明,不同的抗氧化剂会降低...探究了抗氧化剂的种类、抗氧化剂2,6-二叔丁基-4-甲基苯酚(BHT)的用量及其添加方式对乙烯-醋酸乙烯共聚物(EVA )/线型低密度聚乙烯(LLDPE)硅烷交联材料的接枝率、吸光比( R )、耐热性能和力学性能的影响。结果表明,不同的抗氧化剂会降低EVA/LLDPE硅烷交联材料的吸光比和维卡软化温度,但提高其拉伸强度和断裂伸长率。适量的BHT能较好保持EVA/LLDPE硅烷交联材料的性能,当BHT用量为0.22%,吸光比和拉伸强度最大,而且把BHT添加到B料中,使得样品各项性能保持最佳。展开更多
In this paper, the optimum process parameters were obtained through treating phenol of simulated semi-coking wastewater using heat, Fe2＋, Fe^0 and semi-coke to catalyze persulfate. The results of phenol decomposition...In this paper, the optimum process parameters were obtained through treating phenol of simulated semi-coking wastewater using heat, Fe2＋, Fe^0 and semi-coke to catalyze persulfate. The results of phenol decomposition using PS catalyzed by heating, Fe2＋, Fe^0 and semi-coke were compared for selecting a better activating way. The article investigated the effects of temperature, catalyzer dosage, pH value and reaction time. The experiment showed the four methods can all catalyzed the process. Under the experimental conditions of heating, Fe2＋, Fe^0 and semi-coke degradation rate could reach to 20.7%, 75.1%, 94.5% and 40.0%, respectively. On this basis, this study established an Lt6（45） table to analyze the main influencing factors in semi-coke/Fe^0 catalyzing system. Under the optimum conditions, the degradation rate of Phenol reached to 93.6%. However, the PS dosage was reduced by 14.4%.展开更多
Liquid phase oxidation of toluene is an environmental benign route for the production of benzoic acid.In a φ48mm bubble column reactor,the commercial process of toluene liquid phase oxidation was conducted with Co(CH...Liquid phase oxidation of toluene is an environmental benign route for the production of benzoic acid.In a φ48mm bubble column reactor,the commercial process of toluene liquid phase oxidation was conducted with Co(CH3COO)2.4H2O as catalyst.The Co2+ concentration [Co2+] was determined by extraction spectrophotometry and hereby the Co3+ concentration [Co3+] was obtained by mass balance.The results showed that [Co3+] reached the maximum at about 25-30min.[Co3+] increased with increasing Co catalyst amount at total Co concentration<150 mg.L-1 of toluene.The conversion of toluene,yield and selectivity of benzoic acid increased with the increasing [Co3+/Co2+] max.A high [Co3+] and a high [Co3+]/[Co2+] ratio are beneficial to the reaction.展开更多
The inactivation of bacterial cells through catalyzed oxidation using hydrogen peroxide as the primary oxidant agent is dependent on a series of factors, such as the concentration of the catalyst, the rate of hydroxyl...The inactivation of bacterial cells through catalyzed oxidation using hydrogen peroxide as the primary oxidant agent is dependent on a series of factors, such as the concentration of the catalyst, the rate of hydroxyl radical formation in the controlled decomposition of the oxidant agent, and the concentration and toxicity of hydrogen peroxide. The objective of this study was to develop a mathematical model able to predict the kinetics of the inactivation Escherichia coli and total coliforms cells present in treated domestic sewage through catalytic peroxidation. The catalyst used was iron oxide supported on mineral coal （called CP）, and the effects of the operational conditions, including hydrogen peroxide concentration and dosage of catalyst, were evaluated. The results showed that the disinfection kinetics of the treated domestic sewage is dependent on the concentrations of hydrogen peroxide and catalyst dosage. The kinetic model was shown to be able to predict the behavior of the inactivation kinetics of the bacterium Escherichia coli ATCC-25922 when different concentrations of hydrogen peroxide （75 and 100 mg·L^-1） were used, regardless of the catalyst dosage.展开更多
A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m （TiO2）： m （H3PW6Mo6O40） is 1：2.0, volume of water is 30 mL, the reflux react...A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m （TiO2）： m （H3PW6Mo6O40） is 1：2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn （aldehyde（ketone））： n （glycol）, catalyst dosage and reaction time on yield were investigated. Optimal conditions were： n（aldehyde （ketone））： n （glycol）=1.0 ： 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0%展开更多
Hydroxyl radicals HO are generated under Fenton-like (Fe2++H2O2→HO?+OH?+Fe3+) catalytic conditions upon microwave irradiation. Liquid-phase direct catalytic oxidation of benzene to phenol was obtained using FeSO4 sup...Hydroxyl radicals HO are generated under Fenton-like (Fe2++H2O2→HO?+OH?+Fe3+) catalytic conditions upon microwave irradiation. Liquid-phase direct catalytic oxidation of benzene to phenol was obtained using FeSO4 supported on silica gel as a solid catalyst and hydrogen peroxide as the oxidant. The effects of various parameters, such as the different solvents, the amount of solvent used, the amount of catalyst used, the reaction time, the reaction temperature and the amount of hydrogen peroxide used on the yield of phenol were studied to identify optimum reaction conditions. Conventionally heated reaction gives a phenol yield of 0.6%. A higher phenol yield of 13.9% with a selectivity of 100% is obtained when the reaction mixture was irradiated with micro-wave energy. It is concluded that microwave irradiation offers more effective control of energy input for hydroxyl radical generation that is appropriate for various synthetic reactions.展开更多
Zinc oxide （ZnO） has been used as heterogeneous catalyst for the degradation of Acid Alizarin Black S dye （AAB） in aqueous solutions using UV light irradiation. Experiments were conducted at various operating para...Zinc oxide （ZnO） has been used as heterogeneous catalyst for the degradation of Acid Alizarin Black S dye （AAB） in aqueous solutions using UV light irradiation. Experiments were conducted at various operating parameters. The operating parameters were amount of catalyst （50 rag, 100 mg and 150 mg）, initial concentration of dye （30 mg/L, 50 mg/L and 70 mg/L）, the pH of solution （2, 4, 6, 8, l0 and 12） and the UV light intensity （6 watt and 12 watt）. The progress of the degradation reaction was monitored spectrophotometrically. It was found that the degradation process of AAB solution was accelerated with increased catalyst dosage and decreased initial concentration of AAB. It was also found that the removal efficiency of AAB significantly depend on pH value of solution. The results show that the degradation percent reaches the highest values with pH close to neutral. The data proved that removal percent of dye decreased when 6 watt lamp used instead of 12 watt lamp. The kinetic study confirmed that photocatalytic degradation of AAB dye follows a pseudo first order reaction rate.展开更多
文摘探究了抗氧化剂的种类、抗氧化剂2,6-二叔丁基-4-甲基苯酚(BHT)的用量及其添加方式对乙烯-醋酸乙烯共聚物(EVA )/线型低密度聚乙烯(LLDPE)硅烷交联材料的接枝率、吸光比( R )、耐热性能和力学性能的影响。结果表明,不同的抗氧化剂会降低EVA/LLDPE硅烷交联材料的吸光比和维卡软化温度,但提高其拉伸强度和断裂伸长率。适量的BHT能较好保持EVA/LLDPE硅烷交联材料的性能,当BHT用量为0.22%,吸光比和拉伸强度最大,而且把BHT添加到B料中,使得样品各项性能保持最佳。
文摘In this paper, the optimum process parameters were obtained through treating phenol of simulated semi-coking wastewater using heat, Fe2＋, Fe^0 and semi-coke to catalyze persulfate. The results of phenol decomposition using PS catalyzed by heating, Fe2＋, Fe^0 and semi-coke were compared for selecting a better activating way. The article investigated the effects of temperature, catalyzer dosage, pH value and reaction time. The experiment showed the four methods can all catalyzed the process. Under the experimental conditions of heating, Fe2＋, Fe^0 and semi-coke degradation rate could reach to 20.7%, 75.1%, 94.5% and 40.0%, respectively. On this basis, this study established an Lt6（45） table to analyze the main influencing factors in semi-coke/Fe^0 catalyzing system. Under the optimum conditions, the degradation rate of Phenol reached to 93.6%. However, the PS dosage was reduced by 14.4%.
基金Supported by the National Natural Science Foundation of China （20576081, 20736009） and the Ph.D. Programs Foundation of Ministry of Education of China （20070610128）.
文摘Liquid phase oxidation of toluene is an environmental benign route for the production of benzoic acid.In a φ48mm bubble column reactor,the commercial process of toluene liquid phase oxidation was conducted with Co(CH3COO)2.4H2O as catalyst.The Co2+ concentration [Co2+] was determined by extraction spectrophotometry and hereby the Co3+ concentration [Co3+] was obtained by mass balance.The results showed that [Co3+] reached the maximum at about 25-30min.[Co3+] increased with increasing Co catalyst amount at total Co concentration<150 mg.L-1 of toluene.The conversion of toluene,yield and selectivity of benzoic acid increased with the increasing [Co3+/Co2+] max.A high [Co3+] and a high [Co3+]/[Co2+] ratio are beneficial to the reaction.
文摘The inactivation of bacterial cells through catalyzed oxidation using hydrogen peroxide as the primary oxidant agent is dependent on a series of factors, such as the concentration of the catalyst, the rate of hydroxyl radical formation in the controlled decomposition of the oxidant agent, and the concentration and toxicity of hydrogen peroxide. The objective of this study was to develop a mathematical model able to predict the kinetics of the inactivation Escherichia coli and total coliforms cells present in treated domestic sewage through catalytic peroxidation. The catalyst used was iron oxide supported on mineral coal （called CP）, and the effects of the operational conditions, including hydrogen peroxide concentration and dosage of catalyst, were evaluated. The results showed that the disinfection kinetics of the treated domestic sewage is dependent on the concentrations of hydrogen peroxide and catalyst dosage. The kinetic model was shown to be able to predict the behavior of the inactivation kinetics of the bacterium Escherichia coli ATCC-25922 when different concentrations of hydrogen peroxide （75 and 100 mg·L^-1） were used, regardless of the catalyst dosage.
基金Acknowledgements： This work was financially supported by the Natural Science Foundation of Hubei Province, China （No. 2005ABA053） and the National Natural Science Foundation of China （No. 20471044）.
文摘A new environmental friendly catalyst, H3PW6Mo6O40/TiO2 was prepared. The optimum conditions have been found, that is, mass ratio of m （TiO2）： m （H3PW6Mo6O40） is 1：2.0, volume of water is 30 mL, the reflux reaction time is 2 h, and activated temperature is 150 ℃. H3PW6Mo6O40/TiO2 was used as catalyst in catalytic synthesis ofacetals and ketals. Effects ofn （aldehyde（ketone））： n （glycol）, catalyst dosage and reaction time on yield were investigated. Optimal conditions were： n（aldehyde （ketone））： n （glycol）=1.0 ： 1.4; mass fraction of catalyst to reactants, 0.8%; reaction time, 1.0 h and cyclohexane as water-stripped reagent, 10 mL. Under these conditions, yields of acetals and ketals can reach 53.0% -86.9 0%
基金supported by the National Natural Science Foundation of China (No.50921002)
文摘Hydroxyl radicals HO are generated under Fenton-like (Fe2++H2O2→HO?+OH?+Fe3+) catalytic conditions upon microwave irradiation. Liquid-phase direct catalytic oxidation of benzene to phenol was obtained using FeSO4 supported on silica gel as a solid catalyst and hydrogen peroxide as the oxidant. The effects of various parameters, such as the different solvents, the amount of solvent used, the amount of catalyst used, the reaction time, the reaction temperature and the amount of hydrogen peroxide used on the yield of phenol were studied to identify optimum reaction conditions. Conventionally heated reaction gives a phenol yield of 0.6%. A higher phenol yield of 13.9% with a selectivity of 100% is obtained when the reaction mixture was irradiated with micro-wave energy. It is concluded that microwave irradiation offers more effective control of energy input for hydroxyl radical generation that is appropriate for various synthetic reactions.
文摘Zinc oxide （ZnO） has been used as heterogeneous catalyst for the degradation of Acid Alizarin Black S dye （AAB） in aqueous solutions using UV light irradiation. Experiments were conducted at various operating parameters. The operating parameters were amount of catalyst （50 rag, 100 mg and 150 mg）, initial concentration of dye （30 mg/L, 50 mg/L and 70 mg/L）, the pH of solution （2, 4, 6, 8, l0 and 12） and the UV light intensity （6 watt and 12 watt）. The progress of the degradation reaction was monitored spectrophotometrically. It was found that the degradation process of AAB solution was accelerated with increased catalyst dosage and decreased initial concentration of AAB. It was also found that the removal efficiency of AAB significantly depend on pH value of solution. The results show that the degradation percent reaches the highest values with pH close to neutral. The data proved that removal percent of dye decreased when 6 watt lamp used instead of 12 watt lamp. The kinetic study confirmed that photocatalytic degradation of AAB dye follows a pseudo first order reaction rate.
