@article {46020, title = {Pyridine immobilised on magnetic silica as an efficient solid base catalyst for Knoevenagel condensation of furfural with acetyl acetone}, journal = {Catalysis Communications}, volume = {124}, year = {2019}, month = {MAY }, pages = {81-85}, type = {Article}, abstract = {

Novel heterogeneous pyridine immobilised magnetic silica (Fe3O4@SiO2-Py) was found to be an efficient, greener and heterogeneous solid base catalyst for the Knoevenagel condensation of furfural with acetylacetone under optimized reaction conditions. The Knoevenagel condensation product 3-(2-furylmethylene)-2,4-pentanedione (FMP), a jet fuel precursor, was produced in high yield of 85\% with 94\% conversion of furfural at 100 degrees C within a period of 4 h. Fe3O4@SiO2-Py catalyst showed excellent stability and recyclability without losing its initial activity.

}, keywords = {furfural, Jet fuel, Knoevenagel condensation, Silica immobilised pyridine, Solid base}, issn = {1566-7367}, doi = {10.1016/j.catcom.2019.03.005}, author = {Tarade, Komal and Shinde, Suhas and Sakate, Sachin and Rode, Chandrashekhar} } @article {47002, title = {Integration of heterogeneous acid and base catalysis for clean synthesis of jet-fuel precursor from carbohydrates}, journal = {ChemistrySelect}, volume = {5}, year = {2020}, month = {JAN }, pages = {392-400}, type = {Article}, abstract = {

C-12 branched alkane fuel precursor was produced from carbohydrates using an efficient integrated solid acid and base catalysis approach involving: i) isomerisation-dehydration of carbohydrates to 5-(hydroxymethyl)furfural (HMF) over solid acid catalyst having both Lewis and Bronsted sites) in a biphasic MIBK (methylisobutylketone): water + DMSO solvent system and ii) Claisen-Schmidt condensation of crude HMF with MIBK over solid base catalyst. Initially, high yield of jet fuel precursor, (E)-1-(5-(hydroxymethyl)furan-2-yl)-5-methylhex-1-en-3-one from pure HMF and MIBK was achieved over basic CaMgAl(231) catalyst. The glucose dehydration to HMF was optimized in biphasic MIBK: H2O-NaCl: DMSO (8:1.5:0.5; v/v/v) system, with complete glucose conversion and 42\% HMF yield over Zr-Mont possessing both Lewis and Bronsted acid sites. In an integrated dehydration + Claisen-Schmidt condensation sequence, Zr-Mont catalyst was filtered off and the crude HMF with MIBK underwent Claisen-Schmidt condensation over CaMgAl(231) catalyst. The overall 32\% yield of Claisen-Schmidt condensation product was achieved from glucose. MIBK acting also as a product extractant, could be recovered upto 80\%.

}, keywords = {Claisen-Schmidt condensation, dehydration, integrated, jet-fuel precursor, renewable}, issn = {2365-6549}, doi = {10.1002/slct.201903735}, author = {Shinde, Suhas and Tarade, Komal and Mitra, Gaurav and Rode, Chandrashekhar} } @article {47027, title = {Magnetically separable catalyst for condensation of renewable aldehydes and 2-methylfuran to saturated cyclic oxygenates}, journal = {Fuel Processing Technology}, volume = {197}, year = {2020}, month = {JAN}, pages = {106191}, type = {Article}, abstract = {

The saturated cyclic ethers produced from biomass derived aldehydes and 2-methylfuran are the potential diesel fuel candidates. The synthesis of saturated cyclic ethers is a two step process which involves acid catalyzed condensation of aldehydes with 2-methylfuran and the subsequent selective furan ring hydrogenation of the condensation products. Here, we designed a novel recyclable magnetic solid acid catalyst such as [Fe3O4@SiO2-Pr-Py-H][2HSO(4)(2-)] and employed for the condensation of 2-methylfuran with formaldehyde as model substrates and reaction parameters were optimized. Under the set reaction conditions, condensation of 2-methylfuran with several other aldehydes were also successfully achieved with very good yields. Further, several supported noble metal catalysts were screened in order to find suitable catalyst system for selective furan ring hydrogenation of condensation products. Among those, 5\% Pd/C was found to be very active and selective for furan ring hydrogenation without formation of ring opened products under very low hydrogen pressure at room temperature. Prepared catalysts were thoroughly characterized with sophisticated techniques.

}, keywords = {fuel additives, Hydrogenation, Hydroxyalkylation-alkylation, Magnetic solid acid, Organosilica}, issn = {0378-3820}, doi = {10.1016/j.fuproc.2019.106191}, author = {Tarade, Komal and Shinde, Suhas and Rode, Chandrashekhar} }