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本文采用高温分解和焙烧硝酸盐的方法合成了一系列Ni基六铝酸盐催化剂BaNiyAl12-yO19-δ (y=0.1、0.3、0.6、0.9和1.0),并对它们在甲烷部分氧化制合成气反应中的催化性能、催化剂表面积碳及活性组分Ni流失等情况进行了考察。结果表明,该催化剂对甲烷部分氧化制合成气反应具有较好的催化活性,在850 ℃,甲烷转化率和CO选择性分别可达92%和95%。并且催化剂BaNiyAl12-yO19-δ (y=0.3)在100小时的POM反应后,催化剂表面积碳很少,积碳量仅为样品净重的0.8%,特别是100小时反应后,催化剂表面活性组分Ni没有发生流失。这种低积碳量和无活性组分Ni流失与催化剂结构中Ni与相邻原子间的强相互作用有关。 相似文献
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The conversion and utilization of natural gas is of significant meaning to the national economy,even to the everyday life of people. However, it has not become a popular industrial process as expected due to the technical obstacles. In the past decades, much investigation into the conversion of methane,predominant component of natural gas, has been carried out. Among the possible routes of methane conversion, the partial oxidation of methane to synthesis gas is considered as an effective and economically feasible one. In this article, a brief review of recent studies on the mechanism of the partial oxidation of methane to synthesis gas together with catalyst development is wherein presented. 相似文献
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QuanliZhu XutaoZhao YouquanDeng 《天然气化学杂志》2004,13(4):191-203
The conversion and utilization of natural gas is of significant meaning to the national economy,even to the everyday life of people. However, it has not become a popular industrial process as expected due to the technical obstacles. In the past decades, much investigation into the conversion of methane,predominant component of natural gas, has been carried out. Among the possible routes of methane conversion, the partial oxidation of methane to synthesis gas is considered as an effective and economically feasible one. In this article, a brief review of recent studies on the mechanism of the partial oxidation of methane to synthesis gas together with catalyst development is wherein presented. 相似文献
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Interest in conversion of natural gas to liquid hydrocarbons (GTL) by Fischer-Tropsch synthesis has grown significantly over the last decade. Most research and development work has focused on syngas production step, which accounts for more than 50% of the total investment. Reducing the cost of syngas production would have great beneficial effects on GTL process. Catalytic partial oxidation of methane (CPOM) to syngas is a slightly exothermic, highly selective, and energy efficient process. It gives syngas with n(H2)/n(CO)=2, directly suitable for F-T synthesis. However, CPOM process has not yet been used commercially. The major engineering problems are the high temperature gradient and the risk of explosion with premixed CH4-O2 mixture, which is within the ignition and explosion limit. In fluidized-bed reactors, the heat transfer is much better, which ensures a more uniform temperature and safer operation. A technology for syngas production by contacting CH4 with limited amount of steam and O2 in a fluidized-bed reactor has been developed[1]. 相似文献
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YanruZhu ZhenhuaLi YuhongZhou HaitaoWang 《天然气化学杂志》2005,14(1):1-3
The 10%Ni/Al2O3 catalyst for partial oxidation of methane was treated by DBD (dielectric barrier discharge) plasma in a continuous system under atmospheric pressure and room temperature by flowing He. It was found that 10%Ni/Al2O3 catalyst treated by plasma presents a higher catalytic activity and an enhanced stability than the catalysts prepared without plasma treatment. The methane conversion over the catalyst treated by plasma is 3%-5% higher than the catalysts untreated by plasma. Moreover,the enhanced dispersion of the catalyst can be achieved by plasma treatment, which can improve the interaction between active species and supports, catalytic activity and the resistance to carbon deposition. 相似文献
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自放热条件下甲烷部分氧化制合成气 总被引:2,自引:0,他引:2
天然气组成的90%以上是甲烷.目前由天然气制合成气的主要方法是水蒸汽重整法,这种方法投资大、设备复杂、能耗高、生产的合成气不适于直接用来合成甲醇和烃类等.甲烷部分氧化可直接制得H2与CO摩尔比为2的合成气,这是一个温和的放热过程、具有大空速和低温等优... 相似文献
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Quanli Zhu~ 《天然气化学杂志》2004,(4)
The conversion and utilization of natural gas is of significant meaning to the national economy, even to the everyday life of people. However, it has not become a popular industrial process as expected due to the technical obstacles. In the past decades, much investigation into the conversion of methane, predominant component of natural gas, has been carried out. Among the possible routes, of methane conversion, the partial oxidation of methane to synthesis gas is considered as an effective and economically feasible one. In this article, a brief review of recent studies on the mechanism of the partial oxidation of methane to synthesis gas together with 相似文献
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TinghuaWu Mingqiao Zhu Zhenjiang Niu Yijun Zhong Yan Guan Ya Liu Qiangu Yan Zelin Li Huilin Wan 《天然气化学杂志》2002,11(3):159-164
The catalytic properties of several supported metal catalysts on different carriers were studied in the partial oxidation of methane (POM) to syngas. In our experiment, supported noble metal catalysts exhibited better performance than the other supported transition metal catalysts. The catalyst performances were significantly influenced by the d-electron configuration of the active metal components and the dispersion of active metal components on the support. A catalyst with a moderate number of unpaired electrons in the d-orbital of the active metal support without obvious acidity or redox activity (e.g. MgO) was suitable for POM performance. The Rh/SiO2 catalyst was the best in the POM reaction, among those investigated. Reaction conditions apparently also affected the POM performance of the catalyst. The conversion of methane and the selectivity for CO increased with the reaction temperature, and a high CH4/O2 ratio was not beneficial for POM performance. 相似文献
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Tinghua Wu Mingqiao Zhu Zhenjiang Niu Yijun Zhong Yan Guan Ya Liu Qiangu Yan Zelin Li Huilin WanZhejiang Normal University Institute of Physical Chemistry Jinhua ChinaZhejiang University Department of Chemical Engineering Hangzhou ChinaXiamen University Department of Chemistry Xiamen China 《天然气化学杂志》2002,(Z2)
The catalytic properties of several supported metal catalysts on different carriers were studied in the partial oxidation of methane (POM) to syngas. In our experiment, supported noble metal catalysts exhibited better performance than the other supported transition metal catalysts. The catalyst performances were significantly influenced by the d-electron configuration of the active metal components and the dispersion of active metal components on the support. A catalyst with a moderate number of unpaired electrons in the d-orbital of the active metal support without obvious acidity or redox activity (e.g. MgO) was suitable for POM performance. The Rh/SiO2 catalyst was the best in the POM reaction, among those investigated. Reaction conditions apparently also affected the POM performance of the catalyst. The conversion of methane and the selectivity for CO increased with the reaction temperature, and a high CH4/O2 ratio was not beneficial for POM performance. 相似文献
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双柱串联色谱一次分析甲烷部分氧化制合成气产物 总被引:6,自引:0,他引:6
采用PorapakN色谱柱,延迟空管和13X分子筛色谱柱串联方法,用一个TCD,通过AnaStar色谱工作站实时采集信号进行在线分析,可成功地一次性和分析POM产品气听CH4,CO,CO2,O2等几处可能组分,消除了两台色谱仪无法同时取样分析和在两个不同TCD检测器上采集数据引起的实验误差,提高了分析的可靠性。 相似文献
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QuanliZhu JianYang JiaxinWang ShengfuJi HanqingWang 《天然气化学杂志》2003,12(1):23-30
The performance of uspported and unsupported molybdenum carbide for the partial oxidation of methane (POM) to syngas was investgated.An evaluation of the catalysts indicates that bulk molybdenum carbied has a higher methane conversion during the initial stage but a lower selectivity to CO and H2/CO ratio in the products.The rapid deactivation of the catalyst is also a significant problem.However,the supported molybdenum carbide catalyst shows a much higher methane conversion,increased selectivity and significantly improved catalytic stability.The characterization by XRD and BET specific area measurements depict an improved dispersion of molybdenum carbide when using alumina as a carrier.The bulk or the supported molybdenum carbide exists in the β-Mo2C phase,while it is transformed into molybdenum dioxide postcatalysis which is an improtant cause of molybdenum carbide deactivation. 相似文献
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QijianZhang DehuaHe QimingZhu 《天然气化学杂志》2003,12(2):81-89
The direct conversion of methane to methanol has attracted a great deal of attention for nearly a century since it was first found possible in 1902, and it is still a challenging task. This review article describes recent advancements in the direct partial oxidation of methane to methanol. The history of direct oxidation of methane and the difficulties encountered in the partial oxidation of methane to methanol are briefly summarized. Recently reported developments in gas-phase homogeneous oxidation, heterogeneous catalytic oxidation and liquid phase homogeneous catalytic oxidation of methane axe reviewed. 相似文献
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The Effect of Nb Loading on Catalytic Properties of Ni/Ce0.75Zr0.25O2 Catalyst for Methane Partial Oxidation
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Sitthiphong Pengpanich Vissanu Meeyoo Thirasak Rirksomboon Johannes Schwank 《天然气化学杂志》2007,16(3):227-234
In this study,the effect of Nb loading on the catalytic activity of Ce_(0.75)Zr_(0.25)O_2-supported Ni catalysts was studied for methane partial oxidation.The catalysts were characterized by BET,H_2 chemisorption,XRD,TPR,TEM and tested for methane partial oxidation to syngas in the temperature range of 400-800℃at atmospheric pressure.The results showed that the activity of methane partial oxidation on the catalysts was apparently dependent on Nb loading.It seemed that the addition of Nb lowered the catalytic activity for methane partial oxidation and increased the extent of carbon deposition. This might be due to the strong interaction between NiO and Nb-modified support and reduction of surface oxygen reducibility. 相似文献
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用浸渍法制备了Pt/MgO催化剂,并采用X射线衍射、X射线光电子能谱、透射电子显微镜和程序升温表面反应等技术对催化剂进行了表征.考察了催化剂对甲烷部分氧化制合成气反应的催化性能.结果表明,Pt/MgO催化剂具有较高的催化活性和选择性,甲烷转化率与合成气选择性在120 h内保持稳定.以金属状态存在的Pt对甲烷分解具有较高的活性,从而使催化剂对甲烷部分氧化反应具有较高的催化活性.活性组分Pt的存在状态和分散状态非常稳定,而Pt/MgO催化剂具有较强的抗积碳能力,使得催化剂在甲烷部分氧化制合成气反应中具有较高的稳定性. 相似文献
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HaitaoWang ZhenhuaLi ShuxunTian 《天然气化学杂志》2003,12(3):205-209
The partial oxidation of methane to synthesis gas is studied in this paper over Ni/Al2O3 catalysts under atmospheric pressure. The effects of Ni loading on the activity and stability of catalysts with 5 mm α-Al2O3 and θ-Al2O3 pellets as supports were measured in a continuous fixed bed reactor. It is found that the optimum Ni loading is 10%. And the effect of reaction conditions on partial oxidation of methane is also studied. The methane conversion and CO selectivity increase with the increase of the reaction temperature and the space velocity on 10%Ni/α-Al2O3 catalysts. The best CH4/O2 mole ratio is 2 for CO selectivity, and the optimum space velocity is 5.4x105 h-1. 相似文献
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Rh/SiO2催化剂上甲烷部分氧化制合成气反应 总被引:4,自引:0,他引:4
利用程序升温脱附、程序升温还原、程序升温表面反应、程序升温反应和化学捕获反应等手段,对Rh/SiO2催化剂上甲烷部分氧化制合成气反应进行了研究.结果表明,Rh/SiO2催化剂上甲烷部分氧化制合成气机理属于热解-氧化反应机理.甲烷首先在催化剂上发生解离吸附,产生具有不同H/C比的化学吸附物种CHx(x=1~3).其中,具有较高H/C比的CHx可能是甲烷部分氧化反应的活性物种,而具有较低H/C比的CHx可能是催化剂上积碳并导致催化剂失活的来源.活性物种CHx在活性氧物种的作用下,生成含氧中间体物种CHxO或继续脱氢.含氧中间体物种进一步分解,即生成CO和H2;CO2也可由CHx或CHxO物种进一步氧
化生成. 相似文献
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含钒杂多酸催化发烟硫酸中甲烷液相部分氧化反应 总被引:8,自引:0,他引:8
以H5PV2Mo10O40 为催化剂,在发烟硫酸中进行了甲烷液相部分氧化,考察了催化剂用量、反应温度、反应时间和发烟硫酸浓度等工艺条件对反应收率的影响. 甲烷在反应中首先转化为硫酸甲酯,硫酸甲酯随后水解为甲醇. 对于甲烷液相部分氧化反应,发烟硫酸中游离的SO3是非常重要的影响因素. 在工艺条件为催化剂用量7.0 mmol, 反应温度473 K, 反应压力3.5 MPa, 反应时间3 h和发烟硫酸中SO3含量50%时,甲烷转化率可达48.5%, 目的产物甲醇收率为41.5%. 相似文献