resumo
Efficient and recyclable liquid-liquid extraction and catalytic oxidative desulfurization (ECODS) systems for the removal of refractory sulfur compounds from liquid fuels are reported that use the cyclopentadienyl molybdenum tricarbonyl complexes [CpMo(CO)(3)Me] (1), [CpMo(CO)(3)(CH2-PC6H4-CO2Me] (2) and [CpMo(CO)(3)CH2COOH] (3) as catalyst precursors. An ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate, was used as both extractant and reaction medium, entrapping the active homogeneous Mo-VI catalysts that are formed in situ under the operating catalytic conditions (aqueous H2O2 as oxidant, 50 degrees C). The high sulfoxidation activity of the catalyst formed from 1 was largely responsible for enabling > 99% desulfurization within 1 h of a model oil containing 1-benzothiophene, dibenzothiophene, 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene (2000 ppm S). The IL/catalyst phase could be repeatedly recycled with no loss of desulfurization efficiency. By sequentially performing extractive desulfurization and ECODS steps, 83-84% sulfur removal was achieved for untreated real diesel and jet fuel samples with initial sulfur contents of ca. 2300 and 1100 ppm, respectively.
palavras-chave
TEMPERATURE IONIC LIQUIDS; OXIDATIVE DESULFURIZATION; ROOM-TEMPERATURE; HYDROGEN-PEROXIDE; DEEP DESULFURIZATION; OLEFIN EPOXIDATION; MOLECULAR-OXYGEN; METAL CATALYSIS; MODEL DIESEL; SELECTIVE OXIDATION
categoria
Chemistry; Engineering
autores
Juliao, D; Gomes, AC; Pillinger, M; Valenca, R; Ribeiro, JC; Goncalves, IS; Balula, SS
nossos autores
Ana Catarina Costa Gomes Alves
Investigador Auxiliar
Diana Julião
Estudante de doutoramento
Isabel Maria de Sousa Gonçalves
Professor associado
Martyn Pillinger
Investigador Principalagradecimentos
This work was partly funded through the projects REQUIMTE-LAQV, POCI-01-0145-FEDER-007265 (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.