Abstract
Alkali and alkaline earth cation-decorated TiO2 nanotube (TNT)-supported rhodium catalysts were synthesized and characterized by inductively-coupled plasma optical emission spectrometer, surface characterization analyzer, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and Fourier transforming infrared spectrum, respectively. Their catalytic performances were evaluated by the hydroformylation of vinyl acetate. Results showed that both the conversion rate of vinyl acetate and selectivity for aldehyde were improved after Rh/TNTs were modified by alkali or alkali-earth cations. Such improved selectivity for aldehyde might be attributed to the presence of alkali or alkaline earth cations which enhanced CO adsorption, while the high conversion rate of vinyl acetate was likely due to the proper interaction of Lewis acid–base between cations modified TNTs and vinyl acetate.
Highlights
Hydroformylation is a classic reaction to produce aldehydes, alcohols or carboxylic acids which are versatile intermediates and building blocks for pharmaceuticals, commodity and fine chemicals [1,2,3,4].researchers have been made much effort to increase the reaction rate of hydroformylation and the selectivity of aldehyde over the past years [5,6]
In the study of literature, we found that a great deal of literature has reported that alkali and alkaline-earth metals, potassium, are used as promoters to increase the activity of iron-based catalyst for Fischer–Tropsch synthesis (FTS) and water-gas shift (WGS) reaction [11,12,13,14,15,16]
The content of Rh or other metal cations in catalysts was studied by inductively coupled plasma optical emission spectrometer analysis, demonstrating that the presence of alkali or alkaline earth cations did not affect the practical loading of bulk Rh in the catalysts since the nominal Rh loading kept constant or even a bit higher when alkali or alkaline earth cations exist
Summary
Researchers have been made much effort to increase the reaction rate of hydroformylation and the selectivity of aldehyde over the past years [5,6]. The hydroformylation of functionalized terminal olefin, such as vinyl acetate, is still a charming topic since its functional group may coordinate to the metal center [7,8]. This chelation may cut down the catalytic activity of catalytic center and have negative effect on the catalyst. It is necessary to develop a new functional catalyst which has better catalytic performance
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.