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Investigation of synthesis route of unsaturated alcohols in the selective dehydration of diols

二醇选择性脱水不饱和醇合成路线研究

基本信息

批准号：
16360398
负责人：
SATO Satoshi
金额：
$ 9.54万
依托单位：
Chiba University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16360398/
关键词：
diols dehydration unsaturated alcohols cerium oxide catalyst reaction mechanism 酸化セリウム

项目摘要

We have recently found that cerium oxide (CeO_2) catalyzed the selective dehydration of 1,3-butanediol into unsaturated alcohols. We purchased equipment of gas chromatography with mass analyzer (GC-MS), Fourier transform infrared spectroscopy (FT-IR), and a soft ware for the calculation of quantum analysis in order to clarify the reaction mechanism for the dehydration of diols into unsaturated alcohols over cerium oxide. The research work has been well developed with the equipment and software introduced in this work.We were able to identify various by-products formed with a small amount in the reaction of diols by using GC-MS. The by-products provide useful information to consider the reaction route. In the model adsorption of 1,3-butanediol on an oxygen-defect site of a Ce_2 surface was investigated with quantum calculations of Density Functional Theory (DFT) and Paired Interacting Orbital (PIO) theory. In the structures optimized with DFT calculation, the two oxygen atoms of the OH … More groups interact with exposed Ce cations at an oxygen-defect site. In the most stable adsorption structure, one hydrogen atom of the 2-position methylene group interacts with the third Ce cation at the oxygen-defect site of the CeO_2(111) surface. In the PIO calculations of 1,3-butanediol-CeO_2(111) systems, the interacting orbitals are clarified. We proposed a reaction mechanism for the dehydration of 1,3-butanediol over CeO_2.We investigated the dehydration of butanediol into unsaturated alcohols over CeO_2 with different particle sizes. The particle size was controlled by the calcination temperature of CeO_2. Catalytic performance in the dehydration of 1,3-butanediol was greatly affected by the particle size. The selectivity to unsaturated alcohols such as 3-buten-2-ol and trans-2buten-1-ol increased with increasing the particle size, while decomposition of 1,3-butanediol into 3-buten-2-one and butanone was catalyzed by CeO_2 with small particles. In the dehydration of 1,3-butanediol, CeO_2 has structure-sensitive catalysis : CeO_2 {111} afacets have active sites for the formation of unsaturated alcohols, and the other surfaces catalyze the side reactions.We have not yet established the observation of adsorption mode of 1,3-butanediol in the FT-IR measurement because of its low volatility. However, in the support of this grant, we have also found that CeO_2, ZrO_2 and several rare earth oxides are effective for the dehydration of 1,4-butanediol into 3-buten-1-ol. Less

我们最近发现氧化铈（CeO_2）催化1，3-丁二醇选择性脱水生成不饱和醇。我们购置了气相色谱-质谱联用仪（GC-MS）、傅里叶变换红外光谱（FT-IR）和量子分析计算软件，以阐明氧化铈催化二醇脱水生成不饱和醇的反应机理。本研究利用GC-MS技术对二元醇反应过程中生成的少量副产物进行了定性分析，为反应路线的选择提供了有用的信息。在该模型中，采用密度泛函理论（DFT）和配对相互作用轨道（PIO）理论研究了1，3-丁二醇在Ce_2表面氧缺陷位上的吸附。在DFT计算优化的结构中，OH的两个氧原子 ...更多信息基团在氧缺陷位点与暴露的Ce阳离子相互作用。在最稳定的吸附结构中，2-位亚甲基上的一个氢原子与CeO_2（111）表面氧缺陷位上的第三个Ce阳离子相互作用。在1，3-丁二醇-CeO_2（111）体系的PIO计算中，澄清了相互作用轨道。提出了1，3-丁二醇在CeO_2上脱水的反应机理。CeO_2的粒径大小受煅烧温度的控制。催化剂粒径对1，3-丁二醇脱水反应的催化性能有很大影响。CeO_2粒径越小，对3-丁烯-2-醇和反式-2-丁烯-1-醇的选择性越高，而对1，3-丁二醇分解为3-丁烯-2-酮和丁酮的选择性越高。在1，3-丁二醇脱水反应中，CeO_2具有结构敏感的催化作用：CeO_2的{111}面具有生成不饱和醇的活性中心，其它表面催化副反应。在此基础上，我们还发现CeO_2、ZrO_2和几种稀土氧化物对1，4-丁二醇脱水生成3-丁烯-1-醇是有效的。少