...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Catalysis science & technology >Differentiation of the C-O and C-C bond scission mechanisms of 1-hexadecanol on Pt(111) and Ru(0001): a first principles analysis
【24h】

Differentiation of the C-O and C-C bond scission mechanisms of 1-hexadecanol on Pt(111) and Ru(0001): a first principles analysis

机译：分化的切断和碳碳键断开Pt(111)和1-hexadecanol机制俄罗斯(0001):第一原理分析

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

C-C and C-O bond scission are important reactions that have been extensively studied experimentally; however, the decomposition mechanism for long-chain alkanols is still not clear. In the present study, density functional theory calculations were performed to study the reaction mechanisms of C-O and C-C cleavage in 1-hexadecanol on Pt and Ru. The adsorption mechanisms and the reaction cycles for 1-hexadecanol (1-C16H34O) decomposition were clarified in this study. The mechanisms include dehydrogenation steps and C-O and C-C cleavage steps. The present calculation results show that the main mechanism of 1-hexadecanol decomposition on Pt(111) is C14H29CH2CH2OH -> C14H29CH2CHOH -> C14H29CH2 COH -> C14H29CH2C -> C14H29CH2CH -> C14H29CH2CH2 -> C14H29CH2CH3, and the C-O bond cleavage mechanism is favored over that of C-C bond cleavage. The major final product is n-hexadecane (C14H29CH2CH3), and the C-O cleavage and the formation of the C14H29CH2CH2 species are the rate-controlling steps. However, on Ru the mechanism is C14H29CH2CH2OH -> C14H29CH2CH2O -> C14H29CH2CHO -> C14H29CH2CO -> C14H29CHCO -> C14H29CH + CO -> C14H29CH2 -> C14H29CH3, and the dominant product is n-pentadecane (C14H29CH3). The rate-controlling steps are the dehydrogenation of C14H29CH2CO into the C14H29CHCO species and the hydrogenation of C14H29CH2 into C14H29CH3 species. The resulting CO is converted into CH4 according to CO -> HCO -> H2CO -> CH2 -> CH3 -> CH4. The rate-limiting step is the formation of HCO. These calculation results clearly show that the C-O bond scission mechanism is favored over the C-C bond scission mechanism on Pt, whereas the opposite situation occurs on Ru; namely, this reaction is strongly metal dependent. The different mechanisms originate from different initial cleavage channels, in which Ca-H scission is preferred for 1-hexadecanol on Pt, whereas O-H scission is the dominant cleavage on Ru. Moreover, it was found that the selectivity and reactivity could be modified by modifying the experimental conditions such as H-2 pressure. Confirming the mechanisms of C-C and C-O cleavage will aid the modification of experimental conditions to obtain high selectivity products. The present calculation results can be extended to other metals, such as Ni, bimetallic alloys, such as Ni/Pt(111), or other alkanol reaction systems.
机译：碳碳和切断债券分离是重要的反应已经进行了广泛的研究实验;长链烷醇还不的机制明确的。理论计算进行了研究切断和碳碳乳沟的反应机制1-hexadecanol Pt和俄文。机制和反应周期1-hexadecanol (1-C16H34O)分解澄清在这个研究。脱氢步骤和切断和碳碳乳沟步骤。1-hexadecanol分解的主要机制C14H29CH2CH2 - > C14H29CH2CH3,切断键劈理机制是在碳碳的青睐债券的乳沟。正十六烷(C14H29CH2CH3),切断乳沟和C14H29CH2CH2物种的形成速率控制步骤。主导产品是n-pentadecane (C14H29CH3)。速率控制步骤脱氢C14H29CH2CO进入C14H29CHCO物种的加氢C14H29CH2 C14H29CH3物种。公司根据公司转化成甲烷- > HCO一步是HCO的形成。结果清楚地表明,切断键断开碳碳键之破裂机制是青睐机制Pt,而相反的情况发生在俄罗斯;金属的依赖。来自不同的初始乳沟渠道,Ca-H分离是首选1-hexadecanol Pt,而地断开了在俄罗斯占主导地位的乳沟。选择性和反应性修改后,对实验条件进行修改例如,氢的压力。碳碳和切断乳沟会帮助修改获得高的实验条件选择性的产品。结果可以扩展到其他金属,如镍、双金属合金,如镍/ Pt(111),或其他烷醇反应系统。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号