02348nas a2200145   4500008004100000245012000041210006900161260000800230300001400238490000700252520176600259100002102025700002502046856013102071       2017                        eng d00aSolvent-free glycerol transesterification with propylene carbonate to glycerol carbonate over a solid base catalyst0 aSolventfree glycerol transesterification with propylene carbonat  cAPR  a4361-43710 v313 aGlycerol transesterification using propylene carbonate (PC) to glycerol carbonate.(GC) could be efficiently performed under solvent-free 'conditions 'wing solid base as catalysts involving non-noble metal oxide in combination with hydrotalcites (HTs). Among all of the catalysts studied for transesterification, the best result was obtained over a calcium-doped hyclrotalcite (Ca-FIT) catalyst, giving 84% conversion of glycerol and almost complete. GC selectivity. The crystal structure of HT was modified by incorporation of Ca and La into FIT, as revealed by X-ray diffraction studies. The temperature-programmed desorption of carbon dioxide study confirmed the presence of the highest basic site density in terms of 1.94 mmol of CO2 desorbed/g of catalyst, responsible for its higher transesterification efficiency of the Ca-HT catalyst. The Fourier transform infrared spectroscopy study showed peaks at 3036 and 3042 cm(-1) for Ca -HT and lanthanum-doped hydrotalcite (La -HT), respectively, confirming the presence of hydrogen bonding between water and interlayer carbonate anions responsible for abstracting proton from the primary hydroxyl group of glycerol to attack over carbonyl carbon of PC. The presence of intercalated carbonate ions is also confirmed by the Raman study, in both PIT and ca-HT catalysts and even after use of the Ca HT catalyst. The thermogravimetry-differential thermal analysis study evidenced the higher thermal stability of the Ca -HT (T-4 = 765 degrees C) catalyst than that of parent HT with a Mg/Al ratio of 3:1 (T4 = 630 degrees C). Various process conditions, such as the temperature, molar ratio of glycerol/PC, and catalyst loading, significantly influenced conversion and selectivity of glycerol: and GC, Tespectively.1 aKondawar, Sharda1 aRode, Chandrashekhar  uhttps://library.ncl.res.in/content/solvent-free-glycerol-transesterification-propylene-carbonate-glycerol-carbonate-over-solid02005nas a2200157   4500008004100000245008700041210006900128260000800197490000800205520143000213100002401643700002101667700002101688700002501709856011301734       2019                        eng d00aCrystalline LaCoO3 perovskite as a novel catalyst for glycerol transesterification0 aCrystalline LaCoO3 perovskite as a novel catalyst for glycerol t  cOCT0 v4753 a<p>LaCoO3 perovskite was synthesized using sol-gel method by nitrate and acetate precursors of La and Co with varying molar ratios of La and Co (1:1, 1:2 and 2:1). This was found to be an unique strategy to obtain highly crystalline LaCoO3 perovskite material without using any chelating agent. The variation of precursors was found to influence their crystallinity however, variation in molar ratio in the range of 0.5-2, did not affect the formation of perovskite framework. The formation of pure perovskite phase (around or &gt; 80%) could be achieved by combination of acetate and nitrate precursors while, the combination of acetate- acetate or nitrate- nitrate precursors resulted in low phase purity for the perovskite due to the formation of secondary phases like La2O3 and Co3O4. Very interestingly, such combination of perovskite and pure oxide phases contributed to enhancement of basic sites which catalyzed the glycerol transestrifiaction with DMC (dimethyl carbonate) to GC (glycerol carbonate) and GD (glycidol). Among all the catalysts studied, NAP-2 showed highest efficiency in terms of 98% glycerol conversion and 77% GC and 22% GD selectivities. The highlight of this work is that first step glycerol transesterification with DMC required basic sites of either metal oxide or perovskite but for cascade reaction involving decarboxylation required both metal oxide as well as LaCoO3 perovskite phase.</p>
1 aPhadtare, Deepshree1 aKondawar, Sharda1 aAthawale, Anjali1 aRode, Chandrashekhar  uhttps://library.ncl.res.in/content/crystalline-lacoo3-perovskite-novel-catalyst-glycerol-transesterification02135nas a2200253   4500008004100000022001400041245011400055210006900169260000800238300001100246490000700257520127700264653002601541653001301567653002301580653002101603100002301624700001801647700002101665700001601686700002401702700002501726856013001751       2021                        eng d  a0019-452200aRole of preparation parameters of Cu-Zn mixed oxide catalyst in solvent free glycerol carbonylation with urea0 aRole of preparation parameters of CuZn mixed oxide catalyst in s  cJUL  a1000900 v983 aSolvent-free carbonylation of glycerol with urea to glycerol carbonate (GC) was achieved over heterogeneous Cu-Zn mixed oxide catalyst. Cu-Zn catalysts with different ratios of Cu:Zn were prepared using co-precipitation (CP) and oxalate gel (OG) methods. As compared to CuO-ZnO(2:1) catalyst prepared by oxalate gel (OG) method, much higher conversion of glycerol and highest selectivity towards glycerol carbonate (GC) was achieved with CuO-ZnO_CP(2:1) catalyst. Physicochemical properties of prepared catalysts were investigated by using XRD, FT-IR, BET, TPD of CO2 and NH3 and TEM techniques. The effect of stoichiometric ratio of Cu/Zn, calcination temperature of CuO-ZnO catalysts and effect of reaction parameters such as molar ratio of substrates, time and temperature on glycerol conversion to GC were critically studied. Cu/Zn of 2:1 ratio, glycerol-urea 1:1 molar ratio, 145 degrees C reaction temperatures were found to be optimized reaction conditions to achieve highest glycerol conversion of 86% and complete selectivity towards GC. The continuous expel of NH 3 from reaction the mixture avoided formation of ammonia complex with CuO-ZnO catalyst. As a result of this, CuO-ZnO catalyst could be recycled up to three times without losing its initial activity.10aCo-precipitation (CP)10aGlycerol10aGlycerol carbonate10aOxalate gel (OG)1 aCharate, Shrinivas1 aShinde, Suhas1 aKondawar, Sharda1 aDesai, Uday1 aWadgaonkar, Prakash1 aRode, Chandrashekhar  uhttps://library.ncl.res.in/content/role-preparation-parameters-cu-zn-mixed-oxide-catalyst-solvent-free-glycerol-carbonylation01303nas a2200217   4500008004100000022001400041245010000055210006900155260000800224300001100232490000700243520058000250653001200830653002400842653001800866653001700884653001900901100002100920700002500941856011900966       2022                        eng d  a2452-223600aIonic liquids for the sustainable transformation of levulinic acid to gamma-valerolactone (GVL)0 aIonic liquids for the sustainable transformation of levulinic ac  cJUN  a1006070 v353 a<p>This short review is focused on recent findings on the role of ionic liquids (ILs) in catalysing the hydrogenation of levulinic acid (LA) to gamma valerolactone (GVL), which is a cascade reaction involving more than one type of reaction. A brief introduction on green aspects of IL as a catalyst followed by various types of ILs being used for hydrogenation of LA to GVL are discussed. The unique characteristics of ILs responsible for hydrogenation reaction are also explained along with the current and upcoming scenario of IL catalysed hydrogenation of LA to GVL.</p>
10aBiomass10aGamma valerolactone10aHydrogenation10aIonic liquid10alevulinic acid1 aKondawar, Sharda1 aRode, Chandrashekhar  uhttps://library.ncl.res.in/content/ionic-liquids-sustainable-transformation-levulinic-acid-gamma-valerolactone-gvl