| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 65712 | Journal of Molecular Catalysis A: Chemical | 2014 | 6 Pages |
•Acetone ammoximation was catalyzed by hollow titanium silicalite using water as solvent.•For the first time, deactivation mechanism of HTS in acetone ammoximation was studied.•Amines, formed by autocatalytic reaction, adsorbed on the active sites of catalyst.•Micropores was blocked mainly by DMNB, formed by oxidative coupling.•For the first time, polynitro-compound was found in ketone ammoximation.
The deactivation mechanism of hollow titanium silicalite (HTS) in aqueous ammoximation of acetone was investigated. Amines and polynitro-compounds, formed by alkaline autocatalytic and oxidative coupling reaction respectively, were determined to be the main by-products. The results showed that deactivation of HTS could be caused by two main reasons: (1) slow deactivation due to by-product amines adsorbed on the active sites of catalyst surface; (2) rapid deactivation in the late period due to by-products, mainly 2,3-dimethyl-2,3-dinitrobutane (DMNB), filling and blocking the pores of catalyst.
Graphical abstractAmines absorbed on the active sites and pore blocking by by-products mainly polynitro-compound DMNB were two main reasons causing HTS catalyst deactivation in the reaction of acetone ammoxidation when using water as solvent.Figure optionsDownload full-size imageDownload high-quality image (149 K)Download as PowerPoint slide
