01769nas a2200265   4500008004100000022001400041245008200055210006900137260007300206300001200279490000800291520089000299653000601189653002301195653001101218653001601229653002801245653002001273100001701293700002501310700002101335700002401356700001701380856010601397       2011                        eng d  a0920-586100aRole of promoters in copper chromite catalysts for hydrogenolysis of glycerol0 aRole of promoters in copper chromite catalysts for hydrogenolysi  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR  a447-4500 v1643 a<p>Various copper chromite catalysts with and without promoters were prepared by simultaneous co-precipitation and digestion technique and the role of promoters (Al, Ba and Zn) was investigated for hydrogenolysis of glycerol to 1,2-propylene glycol (1,2-PG) in both batch and continuous operations. Among various promoters studied, copper chromite catalyst with Ba as a promoter showed the highest activity and selectivity of 85% to 1,2-PG. This catalyst was found to be active for more than 800 h in a continuous operation also. Ammonia TPD results showed that barium promoted copper chromite catalyst had the highest acidity which facilitates the dehydration of glycerol to acetol which is the first step in hydrogenolysis of glycerol to 1,2-PG. The effect of barium content and variation in the promoters combination was also studied. (C) 2010 Elsevier B.V. All rights reserved.</p>10a110a2-Propylene glycol10aAcetol10aAmmonia TPD10aGlycerol hydrogenolysis10aSurface acidity1 aMane, R., B.1 aGhalwadkar, Ajay, A.1 aHengne, Amol, M.1 aSuryawanshi, Y., R.1 aRode, C., V.  uhttps://library.ncl.res.in/content/role-promoters-copper-chromite-catalysts-hydrogenolysis-glycerol-002367nas a2200181   4500008004100000245010700041210006900148260000800217300001600225490000700241520169400248100002201942700002101964700002501985700002902010700002402039856012202063       2016                        eng d00aReductive cyclization of levulinic acid to gamma-valerolactone over non-noble bimetallic nanocomposite0 aReductive cyclization of levulinic acid to gammavalerolactone ov  cDEC  a13032-130390 v553 aBimetallic nanoparticles have diverse applications in catalytic processes owing to the differences in individual properties that contribute to their increased catalytic activity. To further improve the efficiency, they are dispersed in an inert support that enhances the catalytic activity toward organic transformations. In this study, we report simple, facile, and cost-effective chemical route for the fabrication of nanocomposites with Fe-Ni bimetallic nanoparticles supported on montmorillonite (MMT) possessing variation in the Fe and Ni content. These composites are characterized with X-ray diffraction, transmission electron microscopy surface area, and NH3-TPD. Fe Ni bimetallic nanoparticles are well-dispersed within MMT structure having particle sizes of about 30-40 nm. Among various compositions of Fe-Ni/MMT catalysts, composite with 25% Fe and 25% Ni exhibits >99% LA conversion with 98% selectivity to GVL within 1 h. IPA is found to be better solvent for levulinic acid (LA) to gamma-valerolactone (GVL) conversion, while substantial leaching of iron takes place when water is used as a solvent. It is observed that bimetallic sites are responsible for reduction of LA, while strong acidic sites of MMT are favoring subsequent cyclization to GVL. XPS analysis of fresh and reused Fe-Ni/MMT composites suggest that the catalyst surface does not undergo any chemical change during successive cycles, and the catalytic activity is retained up to six cycles. The plausible mechanism for LA to GVL conversion involves reductive cyclization processes through formation of levulinate ester that undergoes lactonization due to synergism in bimetallic nanoparticles and MMT clay.1 aKadu, Brijesh, S.1 aHengne, Amol, M.1 aBiradar, Narayan, S.1 aRode, Chandrashekhar, V.1 aChikate, Rajeev, C.  uhttps://library.ncl.res.in/content/reductive-cyclization-levulinic-acid-gamma-valerolactone-over-non-noble-bimetallic