共查询到20条相似文献,搜索用时 203 毫秒
1.
2.
3.
4.
针对甲醇蒸汽的微通道重整催化反应过程,建立了三维稳态多组分传输反应模型;利用数值模拟分析,分别研究了平行阵列微通道和仿蜂巢分叉微通道在Zn_Cr/CeO2/ZrO2催化剂下的反应情况。通过双速率模型考察这两种流道中操作条件对甲醇蒸汽重整制氢输运规律的影响,发现这两种微通道反应器均可促进甲醇转化率和氢气产率的提高。与常规平行微通道的比较发现,仿蜂巢分叉微通道内反应气流动所需的泵功较小;在相同的加热面积下所能吸收的热量更大,而且更有利于反应器内温度的均匀分布,从而提高甲醇的转化率、减小出口CO的含量。研究结果表明,仿蜂巢分叉微通道结构具有较好的重整制氢综合性能,并可改善氢气产出的品质。 相似文献
5.
6.
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
7.
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
8.
《化工催化剂及甲醇技术》2003,(5):14-17
以质子交换膜燃料电池为例介绍了燃料电池的工作原理、结构、性能等,简述了甲醇蒸汽重整、甲醇分解以及甲醇部分氧化重整制氢为燃料电池提供燃料的催化反应机理、反应条件、催化剂性能等,阐明从甲醇制氢的离子变换膜燃料电池的优越性及应用前景。 相似文献
9.
10.
Advances in H2 production from the aqueous-phase reforming of biomass-derived polyols:A review
下载免费PDF全文
![点击此处可从《化工进展》网站下载免费的PDF全文](/ch/ext_images/free.gif)
生物质多元醇水相重整是一项正在发展的、很有前景的制氢技术。本文对近些年来涌现的生物质多元醇水相重整制氢研究进行了综述,讨论了多元醇水相重整反应热力学,介绍了反应动力学特征,并以此为基础对反应机理、催化剂体系以及工艺条件优化进行了总结。通过与蒸汽重整对比,指出了水相重整制氢技术的优缺点:优点是能耗低、工艺步骤较少、后处理简单;缺点是副反应多,收率低。最后,提出开发更为高效稳定的催化材料、降低催化剂制备成本和优化工艺条件将是未来研究工作的重点。 相似文献
11.
12.
氢能是一种清洁的二次能源,具有绿色环保、零污染、零碳排放等优点。芳烃蒸汽重整制氢原料来源广、单位体积原料产氢量高,在重油焦油清除升级、便携式移动制氢等领域极具应用价值,其核心在于高性能催化剂的开发。文章首先从芳烃重整反应特性、反应网络、动力学模型构建和吸附解离等方面对其反应动力学及机理进行了概述,认为采用热力学理论计算、先进的原位表征技术和严密的逻辑论证实验等综合手段是加深反应动力学和机理认知的关键;其次,按照催化剂组成分类,评述了不同活性组分、载体及助剂的特点,基于镍基双金属活性组分的协同效应、钙钛矿载体的强储/释氧能力和碱性助剂的酸调控作用,指出碱性助剂改性的负载型镍基双金属钙钛矿催化剂是其发展方向。 相似文献
13.
A biomass‐based methanol production process was investigated. The process consists of a biomass gasifier, steam reformer, and methanol synthesis reactor as the main units. Reactors were simulated by applying the kinetic models previously developed and the process was analyzed based on the simulation results. The key parameters, the equivalence ratio in biomass gasification, the temperature in steam reforming, and the recycle of hydrogen in methanol synthesis were identified. These parameters affect the methanol production. The process analysis indicates that the optimal combinations of the parameters can greatly enhance the methanol production and the thermodynamic efficiency. Finally, the elemental analysis for carbon and hydrogen along the process was carried out. 相似文献
14.
格尔木炼油厂100kt/a甲醇装置采用天然气水蒸气转化法制取甲醇合成气,合成气中的氢碳比过高。为解决这一问题,2002年采用烟道气CO2回收技术,将回收的CO2补加至转化反应前,使转化气的组成得到了优化,甲醇产量大幅度提高,天然气单耗降低,甲醇运行效益明显增加。 相似文献
15.
氢气作为重要的清洁能源和化工原料,目前主要来源于化石燃料,而生物质经快速热解制得生物油用于水蒸气催化重整制氢被认为是一种高效、环保、经济的可再生能源制氢途径。本文首先综述了近年来生物油水蒸气催化重整制氢相关反应原料;然后重点讨论了生物油水蒸气催化重整反应催化剂研究近况;总结了生物油水蒸气重整反应机理与动力学分析;最后列举了重整反应器等方面的研究进展。相比于生物油,生物油模型化合物因结构简单、转化率与氢气收率高,得到广泛研究;以Ni为代表的活性金属组分催化活性高,金属间协同作用强;不同类型的载体可增强催化剂的稳定性,碱性载体还可吸收CO2、提高催化剂抗积炭、防烧结等方面的性能;不同结构的反应器在性能方面表现各异,主要以固定床反应器为主。研制高活性、稳定性强的催化剂,提高重整反应的循环稳定性,并总结最符合动力学规律的反应机理,以及研发高效的反应器是今后生物油水蒸气催化重整制氢研究的重点。 相似文献
16.
A kinetic study of the methanol steam reforming reaction was performed over a commercial CuO/ZnO/Al2O3 catalyst (Süd-Chemie, G66 MR), in the temperature range of 200–300 °C. The reactions considered in this work were methanol steam reforming (MSR) and reverse water gas shift (rWGS). Several MSR kinetic rate models developed by different authors were compared and the one was determined that best fitted the experimental data. A kinetic Langmuir–Hinshelwood model was proposed based on the work by Peppley et al. (1999a) . The kinetic expressions that presented the best fit were used to simulate the packed bed reactor with a one-dimensional model. A good agreement between the mathematical model and the experimental data was observed. 相似文献
17.
A kinetic study of ethanol steam reforming to produce hydrogen within the region of kinetic rate control was carried out. A Ni(II)–Al(III) lamellar double hydroxide as catalyst precursor was used. H2, CO, CO2 and CH4 were obtained as products. Using the Langmuir–Hinshelwood (L–H) approach, two kinetic models were proposed. The first was a general model including four reactions, two of them corresponding to ethanol steam reforming and the other two to methane steam reforming. When high temperatures and/or high water/ethanol feed ratios were used, the system could be reduced to two irreversible ethanol steam reforming reactions. 相似文献
18.
研究了并流共沉淀法制备的Pd/ZnO催化剂上的甲醇水蒸气重整制氢反应.考察了钯含量、还原温度、反应温度、重时空速(WHSV)和水-甲醇摩尔比(水醇比)对反应的影响.研究结果表明,当钯质量分数为15.9%,反应温度为523~573 K,还原温度为523~573 K,水醇比为1.0~1.2,WHSV=17.2 h-1时,反应具有较好的CH3OH转化率、CO2选择性、H2产率及较低的出口CO摩尔分数.与铜基催化剂相比,Pd/ZnO催化剂表现出较好的稳定性. 相似文献
19.
20.
Although hydrogen has been found to be the most acceptable fuel for vehicle-mounted fuel cells, the storage and transportation of the gas presents difficulties. As a result, attention has been focused on on-board conversion of more readily available fuels such as methanol. Comparisons have been made of hydrogen generation from methanol and propane. Simulations are based both on thermodynamic and kinetic data. The results show that a mixture of oxidation and steam reforming (indirect partial oxidation) produces more hydrogen than direct partial oxidation. Propane is found to produce more hydrogen per weight carried than methanol, but suffers from the disadvantage that reaction does not start at room temperature. The necessity to fuel a vehicle with an organic fuel and with water is demonstrated. 相似文献