共查询到20条相似文献,搜索用时 15 毫秒
1.
以草酸钠为共沉淀剂,采用共沉淀法制备了以ZnO-ZrO2为载体的镍基乙醇水蒸气重整制氢催化剂(Ni/ZnO-ZrO2)。考察了不同锌锆摩尔比的ZnO-ZrO2负载的镍基催化剂在300~450℃催化乙醇水蒸气重整制氢的反应性能。用TPR、TPO、XRD对催化剂试样进行了表征。结果表明,当n(Zn)∶n(Zr)=1∶1,Ni负载质量分数10%时,催化剂中有镍锌复合氧化物生成,350℃时乙醇转化率达100%,450℃氢气选择性接近90%;TPO结果表明,ZnO-ZrO2复合载体可以降低催化剂上的积炭量。 相似文献
2.
研究了氧化镁负载镍、铁、钴、锰、钼、铜和锡等金属催化剂在乙醇水蒸气重整反应的性能,结果表明在650℃,101.3kpa条件下,所有催化剂的活性都较高,乙醇接近完全转化,而对氢的选择性顺序为:Ni〉Co〉Sn〉Cu〉Fe〉Mo〉Mn。除镍的选择性是随温度上升之外,其他催化剂的选择性都随温度变化有个最佳值。镍催化剂的TPR和XRD表征表明,催化剂中存在3种形态的镍。 相似文献
3.
低镍/ZnO-TiO2催化剂的乙醇水蒸气重整制氢 总被引:1,自引:0,他引:1
为考察低镍负载量对乙醇水蒸气重整制氢催化剂性能的影响,利用沉积-沉淀法(DP)制备了镍负载最质量分率为0.5%~5.0%的Ni/ZnO-TiO2催化剂,并在内径14 mm的固定床管式反应器中对低镍催化剂进行了性能评价.结果表明,低镍/ZnO-TiO2催化剂具有较好的乙醇水蒸气重整制氢性能.在水醇物质的量比为13:1及反... 相似文献
4.
ZHOU Wen-chang 《内蒙古石油化工》2007,(9)
采用共沉淀法、热分解和氢还原等步骤制备了纳米晶载体催化剂Cu-Ni/Al203-SiO2,应用X射线衍射、x射线光电子能谱、扫描电镜对催化剂的体相和表面结构进行了测定,采用固定床反应器考察了催化剂对乙醇水蒸气重整制氢反应的催化性能。实验结果表明,5%Cu-Ni/Al203-SiO2催化剂对乙醇的低温水蒸气重整反应表现出较高的催化活性,350℃时乙醇的转化率已达到100%。在650℃时氢气的选择性可达78.5%。增加铜含量对增加催化剂的活性没有帮助。 相似文献
5.
采用共沉淀法、热分解和氢还原等步骤制备了纳米晶载体催化剂Cu-Ni/Al2O3-SiO2,应用X射线衍射、x射线光电子能谱、扫描电镜对催化剂的体相和表面结构进行了测定,采用固定床反应器考察了催化剂对乙醇水蒸气重整制氢反应的催化性能。实验结果表明,5%Cu-Ni/Al2O3-SiO2催化剂对乙醇的低温水蒸气重整反应表现出较高的催化活性,350℃时乙醇的转化率已达到100%。在650℃时氢气的选择性可达78.5%。增加铜含量对增加催化剂的活性没有帮助。 相似文献
6.
Alumina-supported rhodium catalysts were shown to be active, selective and stable catalysts in the catalytic ethanol steam reforming when the reaction is carried out under pressure (1.1 MPa). Both the nature of the metal precursor salt, the metal loading and the reaction conditions were shown to influence the activity, the selectivity and the stability of the catalysts. Some trends observed when the reaction is carried out under moderate pressure were shown to be different from the conclusions drawn from earlier results obtained at atmospheric pressure. In fact, rhodium catalysts derived from a chlorinated metal precursor were shown to be the most active, selective and stable. 相似文献
7.
用沉积-沉淀法制备了以ZnO为主要组分的多种复合载体(ZnO-Al2O3、ZnO-TiO2、ZnO-MgO、ZnO-CeO2、ZnO-ZrO2)Ni基催化剂,在固定床反应器上考查了催化剂的乙醇水蒸气重整制氢反应性能。结果表明,催化剂复合载体组分对乙醇水蒸气重整制氢性能有影响,其中,在较低温度(400~470℃)Ni/ZnO催化剂的催化性能最优,而在较高温度(485~550℃)Ni/ZnO-TiO2催化剂有相对最优的催化性能。催化剂的XRD、SEM等表征表明,Ni催化剂活性组分分散良好,催化剂颗粒大小较为均匀,同时也观察到使用后的催化剂表面有积炭生成。 相似文献
8.
M. Noelia Barroso Manuel F. Gomez Luis A. Arrúa M. Cristina Abello 《Catalysis Letters》2006,109(1-2):13-19
Aluminum spinels, MAl2O4 with M2+ = Cu, Zn or Ni, were prepared by citrate method and its reactivity in the ethanol steam reforming reaction was studied at
500 °C. They were characterized by TG, BET surface area, XRD, FTIR and TPR techniques. The catalytic behavior depended strongly
on the nature of divalent metal which determines the physico-chemical properties of samples. In all cases, very active catalysts
with a complete ethanol conversion were reached. Hydrogen yield follows the order of ZnAl > NiAl > CuAl. 相似文献
9.
10.
Hydrogen production was carried out via ethanol steam reforming over supported cobalt catalysts. Wet incipient impregnation
method was used to support cobalt on ZrO2, CeO2 and CeZrO4 followed by pre-reduction with H2 up to 677 °C to attain supported cobalt catalysts. It was found that the non-noble metal based 10 wt.% Co/CeZrO4 is an efficient catalyst to achieve ethanol conversion of 100% and hydrogen yield of 82% (4.9 mol H2/mol ethanol) at 450 °C, which is superior to 0.5 wt.% Rh/Al2O3. The pre-reduction process is required to activate supported cobalt catalysts for high H2 yield of ethanol steam reforming. In addition, support effect is found significant for cobalt during ethanol steam reforming.
10% Co/CeO2 gave high H2 selectivity while suffered low conversion due to the poor thermal stability. In contrast to CeO2, 10 wt.% Co/ZrO2 achieved high conversion while suffered lower H2 yield due to the production of methane. The synergistic effect of ZrO2 and CeO2 to promote high ethanol conversion while suppress methanation was observed when CeZrO4 was used as a support for cobalt. This synergistic effect of CeZrO4 support leads to a high hydrogen yield at low temperature for 10 wt.% Co/CeZrO4 catalyst. Under the high weight hourly space velocity (WHSV) of ethanol (2.5 h−1), the hydrogen yield over 10 wt.% Co/CeZrO4 was found to gradually decrease to 70% of its initial value in 6 h possibly due to the coke formation on the catalyst. 相似文献
11.
生物乙醇重整制氢是一种具有良好应用前景的制氢技术,是当前低碳能源领域的研究热点.本文采用离子交换法制备了Ni-Cu/蒙脱土双金属催化剂,并将其应用于乙醇水蒸气重整制氢.采用X射线衍射(XRD)、比表面积测定(BET)、H2-程序升温还原(H2-TPR)和透射电子显微镜(TEM)等表征手段对催化剂的物相结构、织构性质、还原性能、微观形貌等进行了研究.结果表明:Ni、Cu均为乙醇水蒸气重整制氢的活性组分,铜的加入可以减少镍颗粒的尺寸、优化镍组分的分布状态.此外,Ni-Cu双金属催化剂的双功能特性使其优于单一金属催化剂.Ni-Cu/蒙脱土在焙烧温度500℃、水醇比为8∶1、空速为80000 mL/gcat·h,反应进行10 h后,仍保持72.09%的氢气的选择性,说明Ni-Cu/蒙脱土双金属催化剂在乙醇水蒸气重整制氢中具有良好的催化活性和稳定性. 相似文献
12.
13.
14.
介绍甲醇蒸汽重整制氢工艺和催化剂,对甲醇蒸汽重整制氢气技术的生产成本进行分析评价,还介绍甲醇蒸汽重整制氢技术在燃料电池中的应用。 相似文献
15.
介绍甲醇蒸汽重整制氢工艺和催化剂,对甲醇蒸汽重整制氢气技术的生产成本进行分析评价,还介绍甲醇蒸汽重整制氢技术在燃料电池中的应用. 相似文献
16.
详细分析了亚联高科设计的1000Nm3/h甲醇水裂解制氢装置影响甲醇单耗的因素,并提出实际生产中这些因素具体的控制指标。结果表明:水醇比为1.5—2.0,反应温度为Cu系催化1剂最低活性温度,吸附压力达到设计允许最高值,吸附时间按试验数据模拟得出的值来设定,将会明显降低甲醇单耗。 相似文献
17.
Low temperature steam reforming of ethanol in the temperature range of 200–360°C was studied to maximize the production of H2. The optimum reaction conditions in presence of a suitable catalyst can produce mainly the desired products H2 and CO2. Cu/Al2O3 catalysts with six different concentrations ranging from 0 to 10 wt.% Mn, were prepared, characterized and studied for the ethanol-steam reforming reaction. Maximum ethanol conversion of 60.7% and hydrogen yield of 3.74 (mol H2 / mol ethanol converted) were observed at 360°C for catalyst with 2.5 wt.% Mn loading. 相似文献
18.
采用浸渍法制备了一系列CuxZnyAlz催化剂,考察了催化剂焙烧温度和组成对甲醇水蒸汽转化制氢反应性能的影响, 用TG-DTA、XRD和SEM等方法对催化剂性能进行了表征.结果表明:400℃焙烧、Cu/Zn/Al配比(摩尔)为1:1:3.2时,制备的Cu1Zn1Al3.2催化剂具有良好催化性能;Cu1Zn1Al3.2催化剂较为适宜的反应工艺条件为:反应温度240~250℃,水/醇比1.1~1.3,液体质量空速1~2 h-1;甲醇转化率达到100%,二氧化碳选择性大于97%.本研究制备的Cu1Zn1Al3.2催化剂中CuO 含量仅为24.53%(质量),约为通常共沉淀法制备的Cu/Zn/Al催化剂的CuO 含量的50%,但Cu1Zn1Al3.2催化剂对甲醇水蒸汽转化制氢反应性能与共沉淀法相当.为甲醇水蒸汽转化制氢技术用于燃料电池用氢和中小规模制氢过程提供依据. 相似文献
19.