【作者】 褚洪岭；

【导师】 龚凡；

【作者基本信息】 哈尔滨工程大学 ， 应用化学， 2006， 硕士

【摘要】 氢既是重要的工业原料，又是今后主要的二次能源。随着世界范围内环保法规的日益严格以及社会对洁净氢能关注的加深，氢气的需求量正稳步增长。为尽快满足世界对氢资源的需求，解决目前天然气水蒸汽重整制氢工艺能耗高、生产成本高及设备投资大等问题，有必要开展以天然气为原料制氢催化剂及新工艺研究。 本课题是研制一种以天然气为制氢原料的转化催化剂，采用廉价的空气作氧源，在固定床反应气中设置一氧分布器，使氧气沿轴向的氧分布器径向分布进入催化剂床层进行催化反应。氧气与天然气分开进料，不仅保证了反应体系的安全，而且解决了催化剂床层热点问题及能量合理分配问题。这种装置的特点是使大部分原料反应本质为部分氧化反应，控制步骤已成为快速部分氧化反应，能较大幅度地提高天然气制氢的能力。由于反应过程可实现自热，无需外界提供热量，因此不仅可以明显降低制氢过程能耗，提高单位装置的产量，而且反应器可采用廉价耐火材料制造，避免了昂贵的耐高温管做反应器，装置投资也将明显降低。 本课题主要对催化剂及工艺进行研究。在催化剂研究中，进行了载体筛选、助剂确定、活性组分含量确定及催化剂制备方法考察等工作。在工艺研究中，主要进行了反应器结构和天然气绝热转化制氢工艺条件优化工作。反应器结构主要考察了反应器形式、氧分布器分布状态及反应器内径对催化性能及催化剂床层温度分布的影响。工艺条件优化主要考察空气分配比、反应温度、反应压力、空速、原料气中H₂O／CH₄比等工艺条件对催化性能及床层温度分布的影响，并进行500小时催化剂稳定性试验。 经大量实验，最终确定采用以耐高温的MgAl₂O₄尖晶石为载体，添加2％La₂O₃的含8％Ni的镍基催化剂作为天然气绝热催化转化催化剂。研究结果表明，该催化剂对于天然气、空气和水蒸汽转化制氢具有高的活性、选择性和稳定性。 实验表明，在绝热固定床反应器中进行的天然气催化转化制氢反应，适宜的工艺条件为：温度830℃、压力0.8MPa、空速2400h^-1、CH₄／Air／H₂O=1／2.4／2。在适宜条件下进行的催化剂500小时稳定性试验中，CH₄转化率基更多还原

【Abstract】 Hydrogen is not only an important raw material in industry but also chief quadratic energy in the future. The requirement for hydrogen has been increasing since world environment laws have become much stricter and the whole society paid much more attention to the clean hydrogen energy. It is essential to carry out the catalyst and process for the production of hydrogen to meet the global requests for hydrogen energy and to solve problems such as enormous energy consumption, expensive cost of productions, tremendous investments for equipment which are often encountered in the current steam reforming process.The main problem of the project is to develop a new type catalyst used in the conversing process which employs air as the source of oxygen and nature gas as raw material. The process can be taken in the fixed bed with one axial-oxygen distributed device which can lead the oxygen flow by radial direction into the catalyst bed to reactor. It can ensure the system safe, eliminate the hot point in the catalyst bed and make the energy distributed more rational by separating oxygen from natural gas. The outstanding characteristic of the technique is to make the main reaction partial oxidation which is the controlling rate-step and to raise by a wide margin the capacity of plant for producing hydrogen.The proposed process could reduce clearly the energy consumption of hydrogen prediction and raise the output because the process is adiabatic with no imputing heat, at the same time, the investment for plant is more cheaper owing to the reactor make of low priced fire-resistant refractory.The task maily studied the catalysis and the process. We paid attention to screening various supports, determining the content of promoters and establishing the way of catalyst preparation and so on. The process research had emphasized on the structure of the reactor and the optimization of the hydrogen-product technology process factors. The research about the reactors structure focused on the interfere elements with the catalyst activity and the distributed temperature over the catalytic bed which included the reactors shape and inside diameter, the conditions of the oxygen-distributed device. The main optimizations of the process factors were put on the distributed proportion of air, the reaction temperature , the reaction pressure , the volume flow rate , the H2O/CH4 ratio in raw material gas and so on how could influenced on the catalyst activity and the更多还原