期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
Investigation of N-(Hydroxylethyl)pyrrolidone Dehydration over REOx-doped Nano-ZrO2 Catalyst
1
作者 张磊 刘欣梅 阎子峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第3期309-313,共5页
Catalyst plays an important role in the dehydration of N-(hydroxylethyl)pyrrolidone (NHP) to prepare N-vinyl-pyrrolidone (NVP). At present, NVP yield is only about 30% on commercial ZrO2 catalyst. A coupled prec... Catalyst plays an important role in the dehydration of N-(hydroxylethyl)pyrrolidone (NHP) to prepare N-vinyl-pyrrolidone (NVP). At present, NVP yield is only about 30% on commercial ZrO2 catalyst. A coupled precipitation and solid dispersion technique was designed to prepare the nano-ZrO2 catalyst, in which rare earth metal oxides (REOx) was used as electronic promoter. The results indicated that the catalyst doped REOx (S-1.0) exhibits the optimum performance of NHP dehydration at moderate conditions. NHP conversion and NVP selectivity are respectively 97.0%, 82.3%. Of special interest is that the indexes of the catalyst (S-1.0-1.0) are up to 98.4% and 89.2% respectively. Furthermore, this catalyst bears the good stability. It means that nano-ZrO2 doped REOx catalyst might be a potential commercial catalyst for the NHP dehydration. 展开更多
关键词 N-(hydroxylethyl)pyrrolidone DEHYDRATION rare earth metal oxides Nano-ZrO2 catalyst
下载PDF
Effect of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation 被引量:18
2
作者 Anbin Zhou Jun Wang +3 位作者 Hui Wang Hang Li Jianqiang Wang Meiqing Shen 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第3期257-264,共8页
This study was focused on the influence of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation. A series of CeO2 supports with different contents of active oxygen were obtained by adding surfactant ... This study was focused on the influence of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation. A series of CeO2 supports with different contents of active oxygen were obtained by adding surfactant at different synthesis steps. 0.25 wt% Pt was loaded on these CeO2 supports by incipientwetness impregnation methods. The catalysts were characterized by N2 adsorption, X-ray diffraction(XRD), high-resolution transmission electron microscopy(HRTEM), H2 temperature-programmed reduction(H2-TPR), dynamic oxygen storage capacity(DOSC) and in-situ DRIFTS technologies. For S-f supports, the surfactant was added into the solution before spray-drying in the synthesis process, which facilitates more active oxygen formation on the surface of CeO2. After loading Pt, the more active oxygen on CeO2 contributes to dispersing Pt species and enhancing the CO oxidation activity. As for the aged samples,Pt-R-h shows the highest activity above 190 ℃ because of the presence of more partly oxidized Pt^(δ+) species. Thus the activity is also influenced by the states of Pt and the Pt^(δ+) species may contribute to the high activity at elevated temperature. 展开更多
关键词 CeO2 Active oxygen Pt/CeO2 catalyst Pt dispersion CO oxidation rare earths
原文传递
Effect of high temperature pretreatment on the thermal resistance properties of Pd/CeO2/Al2O3 close-coupled catalysts 被引量:3
3
作者 黄木兰 王苏宁 +3 位作者 兰丽 张海龙 史忠华 陈耀强 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第2期149-157,共9页
Fresh Pd/CeO/AlOclose coupled catalyst was prepared by the stepwise impregnation method and calcined at 550 °C for 3 h, which was then pretreated at 700, 800, and 900 °C for 3 h, respectively. Finally, these... Fresh Pd/CeO/AlOclose coupled catalyst was prepared by the stepwise impregnation method and calcined at 550 °C for 3 h, which was then pretreated at 700, 800, and 900 °C for 3 h, respectively. Finally, these pretreated catalysts were aged at 1000 °C for 3 h to study their anti-aging properties. The catalytic activities of the catalysts were investigated detailedly, and the results showed that the catalyst pretreated at 800 °C before aging treatment possessed the best anti-aging performance for CHoxidation. XRD and XPS results indicated that well-crystallized CeOparticles were formed during calcinations at 800 °C, which made CeOan effective promoter. HRTEM revealed that Pd particles found on the edge of CeOover the aged catalyst pretreated at 800 °C were relatively smaller than those over the catalysts without pretreatment. H-TPR and XPS results also implied that the interaction between well-crystallized CeOand Pd suppressed the deactivation of PdO sites and further enhanced the catalytic performance. 展开更多
关键词 pretreatment temperature C_3H_8 oxidation anti-aging properties close-coupled catalyst rare earths
原文传递
Catalytic liquid-phase oxidation of acetaldehyde to acetic acid over a Pt/CeO_2–ZrO_2–SnO_2/γ-alumina catalyst 被引量:2
4
作者 Pil-Gyu Choi Takanobu Ohno +1 位作者 Toshiyuki Masui Nobuhito Imanaka 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第10期63-66,共4页
Pt/CeO2–ZrO2–SnO2/γ-Al2O3 catalysts were prepared by co-precipitation and wet impregnation methods for catalytic oxidation of acetaldehyde to acetic acid in water. In the present catalysts, Pt and CeO2–ZrO2–SnO2 ... Pt/CeO2–ZrO2–SnO2/γ-Al2O3 catalysts were prepared by co-precipitation and wet impregnation methods for catalytic oxidation of acetaldehyde to acetic acid in water. In the present catalysts, Pt and CeO2–ZrO2–SnO2 were successfully dispersed on the γ-Al2O3 support.Dependences of platinum content and reaction time on the selective oxidation of acetaldehyde to acetic acid were investigated to optimize the reaction conditions for obtaining both high acetaldehyde conversion and highest selectivity to acetic acid. Among the catalysts, a Pt(6.4 wt.%)/Ce0.68Zr0.17Sn0.15O2.0(16 wt.%)/γ-Al2O3 catalyst showed the highest acetaldehyde oxidation activity. On this catalyst, acetaldehyde was completely oxidized after the reaction at 0°C for 8 hr, and the selectivity to acetic acid reached to 95%and higher after the reaction for 4 hr and longer. 展开更多
关键词 Liquid-phase oxidation Acetaldehyde rare earths Catalyst
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部