利用扫描电镜、X射线衍射、紫外-可见漫反射等技术对采用溶胶-凝胶法制备的氮掺杂纳米TiO_2负载活性炭纤维(N-TiO_2/ACF)光催化材料进行了表征分析。以真丝绸染色废水为目标降解物,研究了光催化材料的光催化性能。研究表明:N-TiO_2/ACF...利用扫描电镜、X射线衍射、紫外-可见漫反射等技术对采用溶胶-凝胶法制备的氮掺杂纳米TiO_2负载活性炭纤维(N-TiO_2/ACF)光催化材料进行了表征分析。以真丝绸染色废水为目标降解物,研究了光催化材料的光催化性能。研究表明:N-TiO_2/ACF光催化材料表面的N-TiO_2呈锐钛矿相,粒径约为15.3 nm,其光谱响应范围由紫外光区拓展至可见光区,吸收边带达603 nm;金卤灯照射下反应180 min,0.77 g N-TiO_2/ACF对200 m L真丝绸染色废水降解率达97.2%,2.31 g的N-TiO_2/ACF对200 mL真丝绸染色废水COD去除率达80.6%;N-TiO_2/ACF具有良好的重复使用性能。展开更多
TiO_(2) is a promising photocatalyst,but its practical use is restricted by its low catalytic efficiency caused by the large particle size and uneven size distribution,which arise from the limited contact area of the ...TiO_(2) is a promising photocatalyst,but its practical use is restricted by its low catalytic efficiency caused by the large particle size and uneven size distribution,which arise from the limited contact area of the liquid-liquid interface during synthesis.Impinging stream-rotating packed bed(IS-RPB)reactors,which are used for process intensification,overcome the mixing limitation of traditional stirred-tank reactors and provide a micromixing environment at the molecular scale for the two liquid phases,which can reduce the particle size and distribution range.Cu/N-TiO_(2) nanoparticles were prepared in an IS-RPB reactor by the one-step precipitation method using urea as the nitrogen source,titanyl sulfate as the titanium source,copper chloride as the copper source,and ammonium hydroxide as the precipitant.The particle size of the photocatalyst was about 11.40 nm with a narrow size distribution measured by scanning electron microscopy and transmission electron microscopy.X-ray photoelectron spectroscopy showed that N replaced some O and was uniformly dispersed in the TiO_(2) lattice as interstitial and substitutional N.Cu replaced some Ti and was present as Cu^(2+).The synergistic effects of these two elements formed a new impurity energy level and reduced the band gap energy of the TiO_(2) nanoparticles.The specific surface area of the Cu/N-TiO_(2) nanoparticles was 152.97 m^(2)/g.The effects of the main factors on the degradation rate were studied,and the removal efficiency reached 100%under the optimal operating conditions after 2 h ultraviolet irradiation.The electron paramagnetic resonance measurements showed that the superoxide radical played a main role in the degradation process,whereas the photogenerated holes and hydroxyl radicals had weak effects.展开更多
The selective catalytic reduction(SCR) of NOx using MnOx and CeO2 supported on viscose-based active carbon fibers(ACF) at 120 ℃～270 ℃ relatively lower than the temperature when using V2O5/TiO2-anatase catalyst was ...The selective catalytic reduction(SCR) of NOx using MnOx and CeO2 supported on viscose-based active carbon fibers(ACF) at 120 ℃～270 ℃ relatively lower than the temperature when using V2O5/TiO2-anatase catalyst was studied.As a result,CeO2/ACF shows a better catalysis than MNOx/ACF,which is not affected by the reaction temperature. NO conversion of 85% is reached with the 10%-CeO2/ACF catalyst at the whole temperature window.Furthermore,a series of MnOx-CeO2/ACF composite catalysts were studied.The results show that the loading method of catalyst affects its activity.展开更多
文摘利用扫描电镜、X射线衍射、紫外-可见漫反射等技术对采用溶胶-凝胶法制备的氮掺杂纳米TiO_2负载活性炭纤维(N-TiO_2/ACF)光催化材料进行了表征分析。以真丝绸染色废水为目标降解物,研究了光催化材料的光催化性能。研究表明:N-TiO_2/ACF光催化材料表面的N-TiO_2呈锐钛矿相,粒径约为15.3 nm,其光谱响应范围由紫外光区拓展至可见光区,吸收边带达603 nm;金卤灯照射下反应180 min,0.77 g N-TiO_2/ACF对200 m L真丝绸染色废水降解率达97.2%,2.31 g的N-TiO_2/ACF对200 mL真丝绸染色废水COD去除率达80.6%;N-TiO_2/ACF具有良好的重复使用性能。
基金supported by the Natural Science Foundation of Shanxi Province (201901D211222)the Natural Science Foundation of the Shanxi Province of China (201901D111173)the Scientific and Technological Innovation Programs of Higher Education Institution in Shanxi (2019L0515)
文摘TiO_(2) is a promising photocatalyst,but its practical use is restricted by its low catalytic efficiency caused by the large particle size and uneven size distribution,which arise from the limited contact area of the liquid-liquid interface during synthesis.Impinging stream-rotating packed bed(IS-RPB)reactors,which are used for process intensification,overcome the mixing limitation of traditional stirred-tank reactors and provide a micromixing environment at the molecular scale for the two liquid phases,which can reduce the particle size and distribution range.Cu/N-TiO_(2) nanoparticles were prepared in an IS-RPB reactor by the one-step precipitation method using urea as the nitrogen source,titanyl sulfate as the titanium source,copper chloride as the copper source,and ammonium hydroxide as the precipitant.The particle size of the photocatalyst was about 11.40 nm with a narrow size distribution measured by scanning electron microscopy and transmission electron microscopy.X-ray photoelectron spectroscopy showed that N replaced some O and was uniformly dispersed in the TiO_(2) lattice as interstitial and substitutional N.Cu replaced some Ti and was present as Cu^(2+).The synergistic effects of these two elements formed a new impurity energy level and reduced the band gap energy of the TiO_(2) nanoparticles.The specific surface area of the Cu/N-TiO_(2) nanoparticles was 152.97 m^(2)/g.The effects of the main factors on the degradation rate were studied,and the removal efficiency reached 100%under the optimal operating conditions after 2 h ultraviolet irradiation.The electron paramagnetic resonance measurements showed that the superoxide radical played a main role in the degradation process,whereas the photogenerated holes and hydroxyl radicals had weak effects.
文摘The selective catalytic reduction(SCR) of NOx using MnOx and CeO2 supported on viscose-based active carbon fibers(ACF) at 120 ℃～270 ℃ relatively lower than the temperature when using V2O5/TiO2-anatase catalyst was studied.As a result,CeO2/ACF shows a better catalysis than MNOx/ACF,which is not affected by the reaction temperature. NO conversion of 85% is reached with the 10%-CeO2/ACF catalyst at the whole temperature window.Furthermore,a series of MnOx-CeO2/ACF composite catalysts were studied.The results show that the loading method of catalyst affects its activity.
基金supported by the National Natural Science Foundation of China(0976050)Program for New Century Excellent Talents in University,China(07-0457)National Key Technology Research and Development Program of Tianjin,China(09ZCKFSH01900)~~
