Methylcyclopentenyl Cations Linking Initial Stage and Highly Efficient Stage in Methanol-to-Hydrocarbon Process,ACS Catalysis

当前位置： X-MOL 学术 › ACS Catal. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Methylcyclopentenyl Cations Linking Initial Stage and Highly Efficient Stage in Methanol-to-Hydrocarbon Process
ACS Catalysis ( IF 11.3 ) Pub Date : 2020-03-23 , DOI: 10.1021/acscatal.0c00799
Wenna Zhang ₁ , Mozhi Zhang ₁ , Shutao Xu ₁ , Shushu Gao _{1,

2} , Yingxu Wei ₁ , Zhongmin Liu ₁

Affiliation

In the conversion of methanol to hydrocarbon (MTH), hydrocarbon pool (HCP) species have been observed and demonstrated as important intermediates for efficient formation of olefins in the steady-state stage. However, in situ observation on the formation and evolution of the hydrocarbon pool species at the initial stage is still a huge challenge. In this contribution, experimental and theoretical evidence on the origin and conversion of the methylcyclopentenyl cations (MCP⁺) were obtained directly at the initial period of the MTH reaction. In situ solid-state NMR spectroscopies revealed that MCP⁺ was formed preferentially than polymethylbenzenes (PMBs) species when the HCP species began to accumulate at the transition stage. Additionally, the relationship between MCP⁺ and PMBs species was established by ¹³C-isotope tracing experiments and theoretical calculations. Importantly, this contribution highlights the importance of the MCP⁺ species in the whole methanol conversion process. Besides acting as an important active intermediate species for formation of olefins at the steady-state stage, MCP⁺ species play a crucial role in bridging the direct mechanism at the inefficient initial stage and the highly efficient steady-state stage following the indirect pathway for methanol conversion.

中文翻译：

甲基环戊烯基阳离子连接甲醇制烃过程的初始阶段和高效阶段

在甲醇转化为碳氢化合物（MTH）的过程中，已观察到碳氢化合物库（HCP）物种，并证明它们是在稳态阶段有效形成烯烃的重要中间体。然而，在初始阶段对烃类物质的形成和演化进行原位观察仍然是一个巨大的挑战。在此贡献中，直接在MTH反应的初始阶段获得了有关甲基环戊烯基阳离子（MCP ⁺）的起源和转化的实验和理论证据。原位固态NMR光谱显示MCP ⁺当HCP物种在过渡阶段开始积累时，它比聚甲基苯（PMB）物种优先形成。此外，通过¹³ C同位素示踪实验和理论计算，建立了MCP ⁺和PMBs物种之间的关系。重要的是，这一贡献突出了MCP ⁺物质在整个甲醇转化过程中的重要性。MCP ⁺物质除了在稳态阶段充当重要的活性中间体物种以形成烯烃外，还在桥接甲醇无效途径的低效初始阶段和高效稳态阶段的直接机理中起着关键作用。转换。

更新日期：2020-04-23

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11