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41.
42.
CO2重整甲烷制合成气催化剂六铝酸盐LaNiy/Al12-yO19-δ的研究 总被引:2,自引:2,他引:0
A series of Ni modified hexaaluminates LaNi y Al 12- y O 19- δ ( y =0 3, 0 6, 0 9, 1 0) were prepared by decomposition of nitrates and calcination at high temperature. The crystalline structure and catalytic properties for CO 2 reforming of methane to synthesis gas were investigated by using XRD, XPS, TPR and TGA techniques. The results showed that a pure hexaaluminate LaNi y Al 12- y O 19- δ phase is formed only when y value is in 0< y ≤1. The reduced hexaaluminates LaNi y Al 12- y O 19- δ exhibit significant catalytic activity and stability for the reaction of CO 2 reforming of methane to synthesis gas at 780 ℃, and no deactivation resulting from carbon deposition is found. In the meantime, the catalytic activity is obviously affected by the modifier Ni in the hexaaluminate lattices. Under the same reaction conditions, the conversion of CH 4 and CO 2 increase with increase in the amount ( y value) of the modifier Ni. 相似文献
43.
深黄被孢霉催化转化脂肪醇合成不饱和脂肪酸的初步研究 总被引:3,自引:0,他引:3
The unsaturated fatty acids were biosynthesized by Mortierella isabellina grown on fatty alcohols (butanol, hexadecanol, octadecanol, etc) at 28 ℃ for 5 d and the fatty acid composition was analyzed by gas chromatography. The results showed that more lipid and higher content of the corresponding unsaturated fatty acids could be biosynthesized by the fungi grown on the long chain alcohols. Meanwhile, long chain alcohols were converted more quickly and had higher conversion. It suggests that long chain alcohols are more practical substrates. 相似文献
44.
PengboJiang YongchenShang TiexinCheng YingliBi KeyingShi ShuquanWei GuolinXu KaijiZhen 《天然气化学杂志》2003,12(3):183-188
The decomposition of methane on Ni/a-Al2O3 modified by La2O3 and CeO2 with differ-ent contents has been investigated and the ralationship between methane decomposition and removal of carbon by CO2 over these catalyst has also been studied by pulse-chromatography. The catalysts were characterized by TPR and XRD. It was shown that Ni/a-Al2O3 could be promoted by adding La2O3, and the carbon species produced over this catalyst was activated and eliminated by CO2. But CeO2 would suppress the decomposition of methane over Ni crystallite. Both La2O3 and CeO2 can inhibit aggregation of the Ni particles. Decomposition of methane over the Ni-based catalysts is structure sensitive to a certain extent. 相似文献
45.
Liu Yan Xu Zhanlin Cheng Tiexin Zhou Guangdong Wang Junxia Li Wenxing Bi Yingli Zhen Kaiji 《Kinetics and Catalysis》2002,43(4):522-527
The amount of carbon deposited on hexaaluminate LaNiAl11O19 catalyst in CH4 decomposition and CO2 reforming of methane was determined by means of thermogravimetric analysis (TGA). The properties of carbon formed on the catalysts were characterized by X-ray photoelectron spectroscopy (XPS), temperature-programmed CO2 reaction (TPR-CO2), and temperature-programmed oxidation (TPO) techniques. The experimental results showed that hexaaluminate LaNiAl11O19 catalyst possessed high resistance to carbon deposition in CO2 reforming of methane to synthesis gas at high temperatures, and CO2 played an important role in eliminating carbon during the reaction. At least two forms of the deposited carbon, graphite and carbide, were produced during methane reforming with CO2. 相似文献
46.
47.
The catalytic oxidative coupling of methane was studied over alkali, alkaline-earth and rare-earth metal oxides at 973 K under atmospheric pressure in a continuous flow fixed bed reactor. The catalysts used were prepared by impregnation method. Four alkaline-earth metal oxides were used as support. The temperature dependence of the catalytic properties and the phase composition of the catalysts were also detected.
, 973 - . . . .相似文献
48.
Junxia Wang Dawei Meng Xiuling Wu Jianhe Hong Daizong An Kaiji Zhen 《Reaction Kinetics and Catalysis Letters》2009,96(1):65-73
CO2 reforming of CH4 over hexaaluminates LaNi
x
Mg1−x
Al11O19+δ
and LaNi
x
Mg0.8Al11.2−x
O19+δ
were studied. XRD analysis confirmed that modifier Ni as well as Mg was inlaid into the hexaaluminate lattice. Hexaaluminate
LaNi
x
Mg1−x
Al11O19+δ
(1.0 ≥ x ≥ 0.4) showed better catalytic activities and higher resistance to carbon deposition, which was attributed to their pure
magnetoplumbite-type structure. For this reaction, x-value between 0.6 and 0.4 was the most suitable. 相似文献
49.
50.
Jie Liu Xueju L? Guangdong Zhou Kaiji Zhen Wenxiang Zhang Tiexin Cheng 《Reaction Kinetics and Catalysis Letters》2006,88(2):315-324
Summary Effect of KCl on the structure and the catalytic properties of CuCl2/γ-Al2O3 catalyst for ethane oxychlorination has been studied by means of solubility test, UV-vis spectroscopy, XRD, TPR, TEM and catalytic
reaction. Addition of KCl decreases the interaction between active species CuCl2 and γ-Al2O3 and increases the catalytic properties by accelerating the Cu(II) → Cu(I) reduction step. 相似文献