以CeO_2为载体,制备了负载型复合Ni Fe/CeO_2催化剂,用于乙二醇的水相重整制氢.利用N_2吸附脱附(N_2 adsorption-desorption)、X-射线衍射(XRD)和H2化学吸附(H_2 temperature program reduction)对催化剂的结构进行了表征,并考察了Ni/F...以CeO_2为载体,制备了负载型复合Ni Fe/CeO_2催化剂,用于乙二醇的水相重整制氢.利用N_2吸附脱附(N_2 adsorption-desorption)、X-射线衍射(XRD)和H2化学吸附(H_2 temperature program reduction)对催化剂的结构进行了表征,并考察了Ni/Fe摩尔比对乙二醇水相重整制氢效果的影响以及催化剂的可重复使用性.实验结果表明:在Ni_1Fe_2/CeO_2催化剂上的乙二醇水相重整制氢反应中,H_2选择性为89.27%,,乙二醇转化率为99.13%,,烷烃选择性为11.43%,;催化剂重复使用5次以后,仍然保持初始活性的65%,左右.展开更多
在选择催化还原(selective catalytic reduction,SCR)反应中,SO_2对脱硝催化剂活性具有重要影响.通过浸渍法制备的金属有机骨架(metal-organic frameworks,MOFs)MIL-100(Fe)(materials of Institute Lavoisier,MIL)担载CeO_2的CeO_2/MIL...在选择催化还原(selective catalytic reduction,SCR)反应中,SO_2对脱硝催化剂活性具有重要影响.通过浸渍法制备的金属有机骨架(metal-organic frameworks,MOFs)MIL-100(Fe)(materials of Institute Lavoisier,MIL)担载CeO_2的CeO_2/MIL-100(Fe)催化剂在250℃含有500×10^(-6) SO_2的条件下,对NO_x转化率在10h内可以稳定在91%以上,高于MIL-100(Fe)催化剂的83%.原位红外漫反射傅里叶变换谱实验结果表明,SO2会导致MIL-100(Fe)催化剂表面B酸性位上NH_4^+物种的吸附强度降低,由此导致了含硫SCR反应中NO_x转化率下降.CeO_2/MIL-100(Fe)催化剂中由于添加了CeO_2,有效地减弱了SO2对催化剂表面B酸性位上NH_4^+物种吸附强度的影响,提高了含硫条件下NO_x的转化率,增强了复合催化剂在SCR反应中的抗硫性能.展开更多
采用浸渍法成功合成了新型催化剂纳米Fe3O4/CeO_2,并且用Fe3O4/CeO_2-H_2O_2非均相Fenton体系对TCE进行降解研究,考察了初始pH、H_2O_2浓度、温度及催化剂投加量等因素对于TCE降解效率的影响.实验结果表明,Fe3O4/CeO_2-H_2O_2非均相Fen...采用浸渍法成功合成了新型催化剂纳米Fe3O4/CeO_2,并且用Fe3O4/CeO_2-H_2O_2非均相Fenton体系对TCE进行降解研究,考察了初始pH、H_2O_2浓度、温度及催化剂投加量等因素对于TCE降解效率的影响.实验结果表明,Fe3O4/CeO_2-H_2O_2非均相Fenton体系对TCE具有较好的去除效果:在初始pH=3,温度50℃,H_2O_2浓度30 mmol·L-1和Fe3O4/CeO_2投加量0.5 mg·L-1时,TCE去除率高达97.29%.同时实验结果表明pH在2~7范围内对TCE均有降解效果,所以相对于传统Fenton体系,该体系拥有更宽pH应用范围.目标污染物的降解符合一级动力学,反应活化能为30.77 k J·mol-1,表明反应易于进行.展开更多
In this paper,magnetic composite Fe3 O4/CeO2(MC Fe/Ce) was synthesized via CeO2 covered onto the surface of Fe3O4 by sol-precipitation method.The as-synthesized samples were characterized by FE-SEM,XRD,SEM-EDS and F...In this paper,magnetic composite Fe3 O4/CeO2(MC Fe/Ce) was synthesized via CeO2 covered onto the surface of Fe3O4 by sol-precipitation method.The as-synthesized samples were characterized by FE-SEM,XRD,SEM-EDS and FT-IR spectrum.The pseudo-second-order(PSO) kinetic can describe well the adsorption of Acid black 210(AB210) onto the as-obtained MC Fe/Ce of which the adsorption isotherm fits the Langmuir adsorption model better than Freundlich adsorption model.Furthermore,the maximum monolayer adsorption capacity of MC Fe/Ce is about 93 mg/g,which is 6 times more than that of commercial CeO2 for AB210.Moreover,the removal rate of the adsorbates for AB210 is 82.3% after first adsorption and still about 70% the fourth forth adsorption experiments within 120 min,which demonstrates that the obtained MC Fe/Ce has outstanding adsorption capacity and good stability.Additionally,the composite can be easily separated from aqueous solution in a few seconds with an external magnetic field due to its magnetic property,which is vital and has potential for its practical applications.展开更多
文摘以CeO_2为载体,制备了负载型复合Ni Fe/CeO_2催化剂,用于乙二醇的水相重整制氢.利用N_2吸附脱附(N_2 adsorption-desorption)、X-射线衍射(XRD)和H2化学吸附(H_2 temperature program reduction)对催化剂的结构进行了表征,并考察了Ni/Fe摩尔比对乙二醇水相重整制氢效果的影响以及催化剂的可重复使用性.实验结果表明:在Ni_1Fe_2/CeO_2催化剂上的乙二醇水相重整制氢反应中,H_2选择性为89.27%,,乙二醇转化率为99.13%,,烷烃选择性为11.43%,;催化剂重复使用5次以后,仍然保持初始活性的65%,左右.
文摘在选择催化还原(selective catalytic reduction,SCR)反应中,SO_2对脱硝催化剂活性具有重要影响.通过浸渍法制备的金属有机骨架(metal-organic frameworks,MOFs)MIL-100(Fe)(materials of Institute Lavoisier,MIL)担载CeO_2的CeO_2/MIL-100(Fe)催化剂在250℃含有500×10^(-6) SO_2的条件下,对NO_x转化率在10h内可以稳定在91%以上,高于MIL-100(Fe)催化剂的83%.原位红外漫反射傅里叶变换谱实验结果表明,SO2会导致MIL-100(Fe)催化剂表面B酸性位上NH_4^+物种的吸附强度降低,由此导致了含硫SCR反应中NO_x转化率下降.CeO_2/MIL-100(Fe)催化剂中由于添加了CeO_2,有效地减弱了SO2对催化剂表面B酸性位上NH_4^+物种吸附强度的影响,提高了含硫条件下NO_x的转化率,增强了复合催化剂在SCR反应中的抗硫性能.
文摘采用浸渍法成功合成了新型催化剂纳米Fe3O4/CeO_2,并且用Fe3O4/CeO_2-H_2O_2非均相Fenton体系对TCE进行降解研究,考察了初始pH、H_2O_2浓度、温度及催化剂投加量等因素对于TCE降解效率的影响.实验结果表明,Fe3O4/CeO_2-H_2O_2非均相Fenton体系对TCE具有较好的去除效果:在初始pH=3,温度50℃,H_2O_2浓度30 mmol·L-1和Fe3O4/CeO_2投加量0.5 mg·L-1时,TCE去除率高达97.29%.同时实验结果表明pH在2~7范围内对TCE均有降解效果,所以相对于传统Fenton体系,该体系拥有更宽pH应用范围.目标污染物的降解符合一级动力学,反应活化能为30.77 k J·mol-1,表明反应易于进行.
基金Project supported by the Capacity Building Program of Shanghai Local Universities(12160503600)
文摘In this paper,magnetic composite Fe3 O4/CeO2(MC Fe/Ce) was synthesized via CeO2 covered onto the surface of Fe3O4 by sol-precipitation method.The as-synthesized samples were characterized by FE-SEM,XRD,SEM-EDS and FT-IR spectrum.The pseudo-second-order(PSO) kinetic can describe well the adsorption of Acid black 210(AB210) onto the as-obtained MC Fe/Ce of which the adsorption isotherm fits the Langmuir adsorption model better than Freundlich adsorption model.Furthermore,the maximum monolayer adsorption capacity of MC Fe/Ce is about 93 mg/g,which is 6 times more than that of commercial CeO2 for AB210.Moreover,the removal rate of the adsorbates for AB210 is 82.3% after first adsorption and still about 70% the fourth forth adsorption experiments within 120 min,which demonstrates that the obtained MC Fe/Ce has outstanding adsorption capacity and good stability.Additionally,the composite can be easily separated from aqueous solution in a few seconds with an external magnetic field due to its magnetic property,which is vital and has potential for its practical applications.