An organic‐inorganic heterogeneous catalyst based on Keplerate polyoxometalates for oxidation of dibenzothiophene derivatives with Hydrogen peroxide

Abstract

An organic-inorganic material (NH 4 ) 2 (MimAM) 40 [Mo 132 O 372 (CH 3 COO) 30 (H 2 O) 72 ] have been synthesized by reacting [(NH 4 ) 42 [Mo VI 72 Mo V 60 O 372 (CH 3 COO) 30 (H 2 O) 72 ] with the ionic liquid 3-Aminoethyl-1-methylimidazolium bromide. The catalyst showed remarkably a high catalytic performance in the oxidation of dibenzothiophene (DBT) derivatives with H 2 O 2 35% as a safe and green oxidant. The main parameters affecting the process including catalyst, acid additive, hydrogen peroxide amounts and temperature have been investigated in detail. Sulfur removal of DBT in n-heptane reached to 98.3% yield at 40°C using 2.5 mmol H 2 O 2 and 100 mg of (NH 4 ) 2 (MimAM) 40 [Mo 132 O 372 (CH 3 COO) 30 (H 2 O) 72 ] after 90 min. Underthe optimal conditions, BT (benzothiophene), DBT (dibenzothiophene) and 4,6-DMDBT (4,6-dimethyl-dibenzothiophene) achieved high desulfurization efficiency. Our results showed that the reactivity order of different model sulfur compounds are thiophene <4,6-dimethyl dibenzothiophene< dibenzothiophene. The catalysts could be easily separated from the reaction solution by simple filtration and recycled for several times without loss of activity.

Novel Enzyme-Free Multifunctional Bentonite/Polypyrrole/Silver Nanocomposite Sensor for Hydrogen Peroxide Detection over a Wide pH Range

“…Moreover, H 2 O 2 is ubiquitously generated as a by-product during cholesterol [9], glucose [10], glutamate [11], and lactate [12] oxidation processes. Numerous efforts are spent to develop efficient analytical methods for the detection of H 2 O 2 , namely, high-pressure liquid chromatography, colorimetric, positron emission tomography, electrochemical, bioluminescence and chemiluminescence [13,14,15,16,17]. Unlike these approaches, the electrochemical methods [18] have various advantages, including the low cost, safety, simplicity, accuracy, fast response, and high sensitivity, which are essential for the practical applications [19].…”

Ultradeep desulfurization of model oil through the oxidative adsorption process using Dawson‐type polyoxometalates and graphene oxide multifunctional composites

“…Among the relevant fuel purification technologies, organosulfur removal from transport fuels is regarded as one of the issues of most concern because the presence of organosulfur in transport fuels directly or indirectly causes various environmental and health problems, namely the formation of pollutant particles, the development of acid rain, the corrosion of automobile tail gas treatment devices, and the increase in etiologic factors of respiratory disease and cancer . More recently, governments have implemented the Euro V standard to limit the sulfur content to a level of 10 ppm . Under this background, the ultradeep desulfurization of transport fuels including gasoline, aviation gasoline, light or heavy diesel oil, and fuel oil has received general attention in both academia and industry .…”