01904nas a2200265   4500008004100000022001400041245012400055210006900179260007300248300001200321490000700333520090600340653001901246653005301265653002201318653001701340653003801357100002101395700002301416700001701439700002501456700001801481700001701499856012201516       2010                        eng d  a0169-131700aAcidity tuning of montmorillonite K10 by impregnation with dodecatungstophosphoric acid and hydroxyalkylation of phenol0 aAcidity tuning of montmorillonite K10 by impregnation with dodec  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAR  a164-1700 v483 a<p>Acidity tuning of montmorillonite K10 (mont K10) was achieved by impregnating with dodecatungstophosphoric acid (DTP). The effect on the hydroxyalkylation of phenol was studied at 353 K with phenol to formaldehyde molar ratio of 5. The nature and strength of acid sites were determined by NH(3)-TPD measurement while the distribution of Brensted and Lewis acid sites expressed as B/L ratio, was determined by pyridine IR technique. Among various loadings of DTP (5-60%) studied for the hydroxyalkylation of phenol, 20% DTP/mont K10 showed the highest catalyst activity (90% selectivity to bisphenol F with 28% conversion of phenol). Both total concentration of acid sites and the distribution of acid sites in a high temperature region were required for the high bisphenol F selectivity. Our catalyst (20% DTP/Mont K10) could be recycled three times. (C) 2009 Elsevier B.V. All rights reserved.</p>10aAcidity tuning10aDodecatungstophosphoric acid/Montmorillonite K1010aHydroxyalkylation10aImpregnation10aTemperature programmed desorption1 aGarade, Ajit, C.1 aKshirsagar, V., S.1 aMane, R., B.1 aGhalwadkar, Ajay, A.1 aJoshi, U., D.1 aRode, C., V.  uhttps://library.ncl.res.in/content/acidity-tuning-montmorillonite-k10-impregnation-dodecatungstophosphoric-acid-and-001646nas a2200277   4500008004100000022001400041245008400055210006900139260005700208300001200265490000800277520071600285653000601001653001801007653002401025653001301049653002901062100002101091700002101112700002501133700002801158700002301186700002101209700002901230856010901259       2010                        eng d  a1011-372X00aCu:Al Nano catalyst for selective hydrogenolysis of glycerol to 1,2-propanediol0 aCuAl Nano catalyst for selective hydrogenolysis of glycerol to 1  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcMAR  a141-1470 v1353 a<p>Non-chromium Cu:Al nano catalyst prepared by simultaneous co-precipitation and digestion method without any template or stabilizer, showed three times higher activity than the bulk Cu-Cr catalyst for hydrogenolysis of glycerol in both isopropanol and water solvents, with the selectivity to 1,2-Propanediol (1,2-PDO) as high as 91% at 493 K and H(2) pressure of 7 MPa in 5 h. XRD pattern showed the presence of Cu(+) species in the activated Cu: Al nano catalyst. Although Cu(+) is catalytically inactive in glycerol hydrogenolysis reaction, the presence of Cu(+) helps to stabilize the particle size in a narrow range of 7-11 nm by inhibiting the sintering of copper particles under reaction conditions.</p>10a110a2-Propanediol10aCu:Al nano catalyst10aGlycerol10aSelective hydrogenolysis1 aMane, Rasika, B.1 aHengne, Amol, M.1 aGhalwadkar, Ajay, A.1 aVijayanand, Subramanian1 aMohite, Pravin, H.1 aPotdar, Hari, S.1 aRode, Chandrashekhar, V.  uhttps://library.ncl.res.in/content/cual-nano-catalyst-selective-hydrogenolysis-glycerol-12-propanediol-001723nas a2200205   4500008004100000022001400041245011500055210006900170260007100239300001400310490000700324520091700331100002801248700002501276700001701301700002101318700002301339700002501362856013001387       2010                        eng d  a1083-616000aSelective hydrogenolysis of glycerol to 1,2-propanediol: comparison of batch and continuous process operations0 aSelective hydrogenolysis of glycerol to 12propanediol comparison  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcNOV  a1393-14000 v143 a<p>The screening of copper chromite catalysts with various promoters such as Al, Zn, and Ba for glycerol hydrogenolysis to 1,2-propanediol (1,2-PDO) in a batch reaction showed that Cu-Cr (Ba) catalyst gave the highest conversion of 34% and selectivity of 84% to 1,2-PDO. In a continuous operation (23 g catalyst bed) the same catalyst showed higher conversion of glycerol and selectivity for 1,2-PDO of 65% and &gt; 90%, respectively, with an on-stream activity of similar to 800 h. Better performance in a continuous operation could be due to the in situ activation of the catalyst, suppression of glycerol cracking to ethylene glycol, as well as excessive hydrogenation of 1,2-PDO to 2-propanol due to lower contact time of 1.3 h as compared to that in a batch operation (5 h). Effects of various process parameters on conversion and selectivity also have been compared for batch and continuous operations.</p>1 aRode, Chandrashekhar, V1 aGhalwadkar, Ajay, A.1 aMane, R., B.1 aHengne, Amol, M.1 aJadkar, Sachin, T.1 aBiradar, Narayan, S.  uhttps://library.ncl.res.in/content/selective-hydrogenolysis-glycerol-12-propanediol-comparison-batch-and-continuous-process-001769nas 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-0