Development of New Generation Ammonia Synthesis Catalyst Process

新一代氨合成的催化剂过程在几个支持者和活性碳（AC）中的发展已经找到了用于氨合成的最有效的催化剂，电子促进剂，如碱性硝酸盐是必要的，必须添加到Ru/AC。Promoter nitrate must be decomposed under hydrogen stream at high temperature to the corresponding oxide or hydroxide （CsNOイイD23イD2 ￣ CsOH， Ba（NOイD23イD2）イD22イD2 ￣ BaO）。在本研究中，发现这一氢处理过程（包括硝酸盐分解和支持AC的部分测量）是激活催化剂的一个重要因素。建议采用氢化治疗，温度升高至550℃，升温速率较低（10℃/分钟）。促进剂分解完成了高达365 ° C的工作，因此在高温下启动了碳支持的甲烷的额外高温治疗。最后一个过程被发现是催化剂激活的关键因素，而Ru颗粒在碳周围部分氢化（给Ru-CsOH相互作用的正确位置）。过量加热（高于550 ° C）带来Ru或碳支持的退化，使穷人的活动成为可能，Ru-CsOH/AC激活的实际上使更多的氨活性高于商业铁催化剂。准备第二代氨酰胺合成催化剂的基本原则已由本研究证实。

Development of New Generation Ammonia Synthesis Catalyst ProcessAmong several supports, active carbon (AC) was found to be most effective in ruthenium catalysts for ammonia synthesis.Electronic promoter such as alkali nitrate is necessary to be added to Ru/AC. Promoter nitrate must be decomposed under hydrogen stream at high temperature to the corresponding oxide or hydroxide (CsNOィイD23ィエD2→ CsOH, Ba(NOィイD23ィエD2)ィイD22ィエD2→ BaO). In this study, this hydrogen treatment process (including nitrate decomposition and partial methanation of the support AC) was found to be quite important to activate the catalysts. The hydrogen treatment is recommended to be carried out with slow heating rate (10℃/min) of temperature increase up to 550℃. Promoter decomposition was completed up to 365℃, so the extra heat treatment at the high temperature initiated the methanation of carbon support. The last process was found to be the key factor of catalyst activation, where carbon surrounding Ru particle is partially hydrogenated (to give a proper situation of Ru-CsOH interaction). The excess heating (above 550℃) brings either Ru sintering or deformation of carbon support, which gives poor activity.Ru-CsOH/AC which is activated properly gives much higher ammonia activity than the commercial iron catalysts. The basic principle to prepare the second generation ammonia synthesis catalyst was established by this study.