Ultrasound-assisted oxidative desulfurization process of liquid fuel by phosphotungstic acid encapsulated in a interpenetrating amine-functionalized Zn(II)-based MOF as catalyst

Abstract

In this work, ultrasound-assisted oxidative desulfurization (UAOD) of liquid fuels performed with a novel heterogeneous highly dispersed Keggin-type phosphotungstic acid (HPWO, PTA) catalyst that encapsulated into an amino-functionalized MOF (TMU-17-NH). The prepared composite exhibits high catalytic activity and reusability in oxidative desulfurization of model fuel. Ultrasound-assisted oxidative desulfurization (UAOD) is a new way to performed oxidation reaction of sulfur-contain compounds rapidly, economically, environment-friendly and safely, under mild conditions. Ultrasound waves can be apply as an efficient tool to decrease the reaction time and improves oxidative desulfurization system performance. PTA@TMU-17-NH could be completely performed desulfurization of the model oil by 20mg of catalyst, O/S molar ratio of 1:1 in presence of MeCN as extraction solvent. The obtained results indicated that the conversions of DBT to DBTO achieve 98% after 15min in ambient temperature. In this work, we prepared TMU-17-NH and PTA/TMU-17-NH composite by ultrasound irradiation for first time and employed in UAOD process. Prepared catalyst exhibit an excellent reusability without PTA leaching and loss of activity.

A Keggin Polyoxometalate Shows Water Oxidation Activity at Neutral pH: POM@ZIF‐8, an Efficient and Robust Electrocatalyst

“…Although to comment exactly on the mechanistic pathway of this catalytic water oxidation by POM@ZIF‐8 is beyond the scope of our project, we presume the water molecule to become associated with Keggin cluster somewhere on its surface (this may be through hydrogen bonding), which is quite common for all POMs . A direct comparison with the earlier reports of Keggin‐catalyzed oxidation of organic substrates also encouraged us for such a logical consideration . As the organic molecules cannot come close to the central X of [XM 12 O 40 ] n − (owing to large size), they should be attached with the surface for facile catalytic reaction.…”

“…[54][55][56][57] Ad irect comparison with the earlier reports of Keggin-catalyzed oxidation of organic substrates also encouraged us for such al ogical consideration. [58][59][60][61][62][63][64] As the organic molecules cannot come close to the central Xof[XM 12 O 40 ] nÀ (owing to large size), they should be attached with the surface for facile catalytic reaction. Thus,in case of WO catalysis by POM@ZIF-8, water can be considered to get associated (mostly,byHydrogen bond formation) with the Keggin surface.S uch association will allow facile electron transport between Keggin and water molecule.…”

A Comprehensive Review on Catalytic Oxidative Desulfurization of Liquid Fuel Oil

“…In the UADO process, the reaction kinetics is better due to increased mass transfer in the heterogeneous reaction system. The reaction rate and mass transfer are also enhanced because of the simultaneous physical and mechanical effects [57][58][59].…”

Mechanistic investigation of Sono–Phosphotungstic acid/phase transfer agent assisted oxidative desulfurization of liquid fuel

“…Tungsten catalysts are more efficient for oxidation of refractory sulfur compounds to their corresponding sulfone in presence of H 2 O 2 . Most of the tungsten agents (Keggin‐type heteropoly acids) are surface active species that reduces the surface tension of the reaction system . Due to reduction in the surface tension, it is easy to generate the microbubble under ultrasound irradiation condition.…”

“…Most of the tungsten agents (Keggin-type heteropoly acids) are surface active species that reduces the surface tension of the reaction system. 10 Due to reduction in the surface tension, it is easy to generate the microbubble under ultrasound irradiation condition. Generation of microemulsification through ultrasound enhances the liquid-liquid interfacial area that is important for cavitation of microbubble.…”