The biodiesel prepared from Xanthoceras Sorbiflia Bunge Oil catalyzed by Ce doped nano PO_4^(3-)/ZrO_2 was investigated. A maximum biodiesel yield of 91.83% was achieved at the concentration of Ce^(3+) up to 0.1 mol/L...The biodiesel prepared from Xanthoceras Sorbiflia Bunge Oil catalyzed by Ce doped nano PO_4^(3-)/ZrO_2 was investigated. A maximum biodiesel yield of 91.83% was achieved at the concentration of Ce^(3+) up to 0.1 mol/L, calcination temperature 500 °C, calcination time 3.0 h, and the concentration of phosphoric acid of 3.5 mol/L. Ce-nano PO_4^(3-)/ZrO_2 catalyst activities were correlated with the observed physico-chemical characteristics derived from scanning electron microscopy(SEM), FT-infrared(FT-IR), X-ray diffraction(XRD), thermogravimetric(TG) and Brunauer-Emmett-Teller(BET) analysis. The delayed crystallization of ZrO_2 made surface oxides have more defects which were beneficial to the adsorption of PO_4^(3-) by the concentration increment of Ce^(3+). The chemical composition of synthesized biodiesel was confirmed by gas chromatography(GC). The characteristics of Xanthoceras Sorbiflia Bunge oil were found within the optimal range in accordance with Chinese No. 0 diesel standard as a substitute diesel fuel.展开更多
Ce-ZrO2 is a widely used three-way catalyst support. Because of the large surface area and excellent redox quality, Ce-ZrO2 may have potential application in selective catalytic reduction （SCR） systems. In the prese...Ce-ZrO2 is a widely used three-way catalyst support. Because of the large surface area and excellent redox quality, Ce-ZrO2 may have potential application in selective catalytic reduction （SCR） systems. In the present work, Ce-ZrO2 was introduced into a low-temperature SCR system and CeO2 and ZrO2 supports were also introduced to make a contrastive study. Mn/CeO2, Mn/ZrO2 and Mn/Ce-ZrO2 were prepared by impregnating these supports with Mn（NO3）2 solution, and have been characterized by N2-BET, XRD, TPR, TPD, XPS, FT-IR and TG. The activity and resistance to SO2 and H2O of the catalysts were investigated. Mn/Ce-ZrO2 and Mn/CeO2 were proved to have better low-temperature activities than Mn/ZrO2, and yielded 98.6% and 96.8% NO conversion at 180℃, respectively. This is mainly because Mn/Ce-ZrO2 and Mn/CeO2 had higher dispersion of manganese oxides, better redox properties and more weakly adsorbed oxygen species than Mn/ZrO2. In addition, Mn/Ce-ZrO2 showed a good resistance to SO2 and H2O and presented 87.1% NO conversion, even under SO2 and H2O treatment for 6 hours, and the activity of Mn/Ce-ZrO2 was almost restored to its original level after cutting off the injection of SO2 and H2O. This was due to the weak water absorption and weak sulfation process on the surface of the catalyst.展开更多
Ce-Zr-Al-Nd2O3 （CZAN） support materials were prepared by co-precipitation and impregnation methods, respectively. They were characterized by X-ray diffTaction （XRD）, low temperature nitrogen adsorption-desorption,...Ce-Zr-Al-Nd2O3 （CZAN） support materials were prepared by co-precipitation and impregnation methods, respectively. They were characterized by X-ray diffTaction （XRD）, low temperature nitrogen adsorption-desorption, oxygen pulsing technique, H2-temperamre programmed reduction （H2-TPR） and X-ray photoelectron spectroscopy （XPS）. The Pd-only three-way catalysts （Pd-TWC） supported on these materials were prepared by incipient wetness method and studied by activity tests. The results demonstrated that the CZAN supports obtained by the two methods showed better structural, textural and redox properties than the CZA without Nd2O3, and the addition of Nd203 improved the catalytic activity of TWC. Especially, the CZAN-i support prepared by impregnation method had better thermal stability and redox property. Meanwhile, the Pd/CZAN-i catalyst exhibited the best catalytic performance. XPS measurements indicated that the Nd-modified samples possessed more Ce3＋ and oxygen vacancies on the surface of samples, which led to a better redox property. The excellent redox property of support materials helped to improve the catalytic activity of TWC.展开更多
基金Supported by Key Laboratory of Bio-based Material Science&Technology(Northeast Forestry University)Ministry of Education(No.SWZCL2016-10)+2 种基金Natural Science Foundation of Inner Mongolia(No.2018BS03004)Talent Development Fund of Inner MongoliaNational Majority R&D Program of China(2017YFD06002025)
文摘The biodiesel prepared from Xanthoceras Sorbiflia Bunge Oil catalyzed by Ce doped nano PO_4^(3-)/ZrO_2 was investigated. A maximum biodiesel yield of 91.83% was achieved at the concentration of Ce^(3+) up to 0.1 mol/L, calcination temperature 500 °C, calcination time 3.0 h, and the concentration of phosphoric acid of 3.5 mol/L. Ce-nano PO_4^(3-)/ZrO_2 catalyst activities were correlated with the observed physico-chemical characteristics derived from scanning electron microscopy(SEM), FT-infrared(FT-IR), X-ray diffraction(XRD), thermogravimetric(TG) and Brunauer-Emmett-Teller(BET) analysis. The delayed crystallization of ZrO_2 made surface oxides have more defects which were beneficial to the adsorption of PO_4^(3-) by the concentration increment of Ce^(3+). The chemical composition of synthesized biodiesel was confirmed by gas chromatography(GC). The characteristics of Xanthoceras Sorbiflia Bunge oil were found within the optimal range in accordance with Chinese No. 0 diesel standard as a substitute diesel fuel.
基金supported by the National Natural Science Foundation of China (No. 51176077,50976050)the Tianjin Municipal Natural Science Foundation Project(No. 12JCZDJC29300)
文摘Ce-ZrO2 is a widely used three-way catalyst support. Because of the large surface area and excellent redox quality, Ce-ZrO2 may have potential application in selective catalytic reduction （SCR） systems. In the present work, Ce-ZrO2 was introduced into a low-temperature SCR system and CeO2 and ZrO2 supports were also introduced to make a contrastive study. Mn/CeO2, Mn/ZrO2 and Mn/Ce-ZrO2 were prepared by impregnating these supports with Mn（NO3）2 solution, and have been characterized by N2-BET, XRD, TPR, TPD, XPS, FT-IR and TG. The activity and resistance to SO2 and H2O of the catalysts were investigated. Mn/Ce-ZrO2 and Mn/CeO2 were proved to have better low-temperature activities than Mn/ZrO2, and yielded 98.6% and 96.8% NO conversion at 180℃, respectively. This is mainly because Mn/Ce-ZrO2 and Mn/CeO2 had higher dispersion of manganese oxides, better redox properties and more weakly adsorbed oxygen species than Mn/ZrO2. In addition, Mn/Ce-ZrO2 showed a good resistance to SO2 and H2O and presented 87.1% NO conversion, even under SO2 and H2O treatment for 6 hours, and the activity of Mn/Ce-ZrO2 was almost restored to its original level after cutting off the injection of SO2 and H2O. This was due to the weak water absorption and weak sulfation process on the surface of the catalyst.
基金Project supported by National Natural Science Foundation of China (20773090, 20803049)the Specialized Research Fund for the Doctoral Program of Higher Education (20070610026, 200806100009)
文摘Ce-Zr-Al-Nd2O3 （CZAN） support materials were prepared by co-precipitation and impregnation methods, respectively. They were characterized by X-ray diffTaction （XRD）, low temperature nitrogen adsorption-desorption, oxygen pulsing technique, H2-temperamre programmed reduction （H2-TPR） and X-ray photoelectron spectroscopy （XPS）. The Pd-only three-way catalysts （Pd-TWC） supported on these materials were prepared by incipient wetness method and studied by activity tests. The results demonstrated that the CZAN supports obtained by the two methods showed better structural, textural and redox properties than the CZA without Nd2O3, and the addition of Nd203 improved the catalytic activity of TWC. Especially, the CZAN-i support prepared by impregnation method had better thermal stability and redox property. Meanwhile, the Pd/CZAN-i catalyst exhibited the best catalytic performance. XPS measurements indicated that the Nd-modified samples possessed more Ce3＋ and oxygen vacancies on the surface of samples, which led to a better redox property. The excellent redox property of support materials helped to improve the catalytic activity of TWC.
