Original Research ARTICLE
Catalytic oxidative desulfurization performance of mesoporous silica versus organosilica composites to treat model and real diesel
- 1Chemistry and Technology Network (REQUIMTE), Portugal
- 2Research Center in Materials, Department of Materials Science, Faculty of Sciences and Technology, New University of Lisbon, Portugal
- 3Faculty of Sciences, University of Lisbon, Portugal
- 4Spanish National Research Council (CSIC), Spain
The monolacunary Keggin-type [PW11O39]7- (PW11) heteropolyanion was immobilized onto the porous framework of mesoporous silicas, namely SBA-15 and an ethylene-bridged periodic mesoporous organosilica (PMOE). The supports were previously functionalized with a cationic functional group (N-trimethoxysilypropyl-N,N,N-trimethylammonium, TMA) for the successful anchoring of the anionic polyoxometalate. The PW11@TMA-SBA-15 and PW11@TMA-PMOE composites were evaluated as heterogeneous catalysts in the oxidative desulfurization of a model diesel. The PW11@TMA-SBA-15 catalyst has shown a remarkable desulfurization performance by reaching ultra-low sulfur levels (<10ppm) after only 60 min using either a biphasic extractive and catalytic oxidative desulfurization (ECODS) (1:1 MeCN/diesel) or a solvent-free catalytic oxidative desulfurization (CODS) system. Furthermore, the mesoporous silica composite was able to be recycled for 6 consecutive cycles without any apparent loss of activity. The promising results have led to the application of the catalyst in the desulfurization of an untreated real diesel supplied by CEPSA (1335 ppm S) using the biphasic system. The system has proved to be a highly efficient process by reaching desulfurization values higher than 90% for real diesel during 3 consecutive cycles.
Keywords: oxidative desulfurization, Heterogeneous catalysis, mesoporous silica, Polyoxometalate (POM), Fuels
Received: 03 Jul 2019;
Accepted: 22 Oct 2019.
Copyright: © 2019 Ribeiro, Granadeiro, Corvo, Pires, Campos-Martín, Castro and Balula. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Salete S. Balula, Chemistry and Technology Network (REQUIMTE), Porto, Portugal, email@example.com