abstract
A combination of catalytic oxidation and extraction was used for the desulfurization of a model diesel containing benzothiophene, dibenzothiophene and 4,6-dimethyldibenzothiophene, or a real diesel sample with a sulfur content of 2300 ppm. The catalysts used were the soluble peroxo compound (nBu(4)N)(3){PO4[WO(O-2)(2)](4)} (PW4) and a supported material denoted as PW4@TMA-SBA-15 that was prepared by immobilization of PW4 in an ordered mesoporous silica (SBA-15) derivatized with propyltrimethylammonium groups (TMA). The supported catalyst was characterized by FT-IR, FT-Raman, P-31 and C-13 MAS NMR spectroscopies, powder X-ray diffraction and scanning electron microscopy. Under optimized conditions (H2O2/S molar ratio = 7, 70 degrees C, acetonitrile as extraction solvent), both catalysts led to complete desulfurization of the model diesel within a reaction time of 2 h. The desulfurization systems could be recycled 10 times with only a slight decrease in performance being observed between the 9th and 10th oxidative desulfurization cycles. Application of the PW4 system to the real diesel led to an outstanding desulfurization efficiency of 89% after a reaction time of 2 h.
keywords
OIL REFINERY STREAMS; HYDROGEN-PEROXIDE; EPOXIDATION; POLYOXOMETALATE; MODEL; OLEFINS; PERFORMANCE; EXTRACTION; ALCOHOLS; SULFUR
subject category
Energy & Fuels; Engineering
authors
Juliao, D; Mirante, F; Ribeiro, SO; Gomes, AC; Valenca, R; Ribeiro, JC; Pillinger, M; de Castro, B; Goncalves, IS; Balula, SS
our authors
Ana Catarina Costa Gomes Alves
Assistant Researcher
Diana Julião
PhD Student
Isabel Maria de Sousa Gonçalves
Associate Professor
Martyn Pillinger
Principal Researcheracknowledgements
This work was partly funded through the projects REQUIMTE-LAQV [FCT (Fundacao para a Ciencia e a Tecnologia) Ref. UID/QUI/50006/2013] and CICECO - Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER (Fundo Europeu de Desenvolvimento Regional) under the PT2020 Partnership Agreement. The FCT and the European Union are acknowledged for grants to D.J. (SFRH/BD/102783/2014) and A.C.G. (SFRH/BPD/108541/2015) co-funded by MCTES and the European Social Fund through the program POPH of QREN.