01482nas a2200157   4500008004100000022001400041245011000055210006900165260007100234300001400305490000700319520083400326100002101160700001701181856012601198       2012                        eng d  a0888-588500aCalcined, rare earth modified hydrotalcite as a solid, reusable catalyst for dimethyl carbonate synthesis0 aCalcined rare earth modified hydrotalcite as a solid reusable ca  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAY  a6356-63630 v513 a<p>An eco-friendly building block and fuel additive dimethyl-carbonate (DMC)-was synthesized through a benign route by transesterification of propylene carbonate (PC) with methanol. The catalytic activity of a series of calcined, rare earth elements (La3+, Ce3+, Pr3+, Sm3+, and Y3+; 2-10 mol %) incorporated Mg-Al hydrotalcites (HT) was evaluated for this reaction. Among several, the La (8 mol %) modified HT showed the highest activity (PC conversion = 65.4 mol % and DMC selectivity = 88 mol % at 150 degrees C and in 2 h). Basicity of the catalyst played an important role on the transesterification activity. The influence of reaction parameters and calcination temperature on the catalytic activity of HT was investigated. The La modified HT catalyst was heterogeneous and could be reused with little loss of activity.</p>1 aUnnikrishnan, P.1 aSrinivas, D.  uhttps://library.ncl.res.in/content/calcined-rare-earth-modified-hydrotalcite-solid-reusable-catalyst-dimethyl-carbonate-001616nas a2200229   4500008004100000022001400041245008700055210006900142260007300211300001000284490000800294520075200302653002201054653002901076653003701105653002401142653001801166653004401184100002101228700001701249856012001266       2015                        eng d  a1381-116900aHighly active and reusable ternary oxide catalyst for dialkyl carbonates synthesis0 aHighly active and reusable ternary oxide catalyst for dialkyl ca  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAR  a42-490 v3983 a<p>The application of ternary oxides, prepared through calcination of rare-earth modified Mg/Al-hydrotalcite (HT), as highly active, selective, and reusable solid catalysts for dialkyl carbonates synthesis by transesterification reaction is reported. Dimethyl carbonate, for example, was prepared by reacting ethylene carbonate with methanol in 100 mol% selectivity at a yield of 95 mol%. Among several rare-earth modified precursors, La (10 mol%)-HT showed the highest activity. This catalyst was active even at ambient conditions. Basicity of the catalyst played crucial role on its performance. The activity of these catalysts was superior to the hitherto known solid catalysts for this reaction. (C) 2014 Elsevier B.V. All rights reserved.</p>10aDialkyl carbonate10aDimethyl carbonate (DMC)10aRare-earth modified hydrotalcite10aSolid base catalyst10aTernary oxide10aTransesterification of cyclic carbonate1 aUnnikrishnan, P.1 aSrinivas, D.  uhttps://library.ncl.res.in/content/highly-active-and-reusable-ternary-oxide-catalyst-dialkyl-carbonates-synthesis-001906nas a2200217   4500008004100000022001400041245011100055210006900166260010200235300001200337490000800349520106200357653002401419653001001443653002001453653002301473653002801496100002101524700002101545856012201566       2016                        eng d  a0974-362600aDirect synthesis of dimethyl carbonate from CO2 and methanol over CeO2 catalysts of different morphologies0 aDirect synthesis of dimethyl carbonate from CO2 and methanol ove  aC V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIAbINDIAN ACAD SCIENCEScJUN  a957-9650 v1283 a<p>The direct synthesis of dimethyl carbonate (DMC) from carbon dioxide (CO2) and methanol is an attractive approach towards conversion of the greenhouse gas - CO2 into value-added chemicals and fuels. Ceria (CeO2) catalyzes this reaction. But the conversion efficiency of CeO2 is enhanced when the byproduct water in the reaction medium is separated by employing trapping agents like 2-cyanopyridine (2-CP). In this work, the influence of morphology of CeO2 on the direct synthesis of DMC in presence of 2-CP is reported. CeO2 catalysts of cube, rod, spindle and irregular morphology (Ce - C, Ce - R, Ce - S and Ce - N, respectively) were prepared, characterized and studied as catalysts in the said reaction conducted in a batch mode. Among all, Ce - S shows superior catalytic performance with nearly 100 mol% of DMC selectivity. Catalytic activity correlates with the concentration of acid and base sites of medium strength as well as defect sites. Ce - S has an optimum number of these active sites and thereby shows superior catalytic performance.</p>10aacid-base catalysis10aceria10aCO2 utilization10aDimethyl carbonate10ainfluence of morphology1 aUnnikrishnan, P.1 aDarbha, Srinivas  uhttps://library.ncl.res.in/content/direct-synthesis-dimethyl-carbonate-co2-and-methanol-over-ceo2-catalysts-different01254nas a2200145   4500008004100000022002000041245002800061210002800089260001800117300001100135520086100146100002101007700001701028856006301045       2016                        eng d  a978-012801457-800aHeterogeneous catalysis0 aHeterogeneous catalysis  bElsevier Inc.  a41-1113 aA majority of industrial catalytic processes use heterogeneous catalysts because of their engineering advantages. At present, heterogeneous catalysis covers almost 80% of the global market share. The demand for heterogeneous catalysis is growing annually. In 2010, it was about US 14 billion and expected estimation of it in 2015 is around 20 billion. Understanding at the molecular level the way surfaces of solids catalyze chemical reactions is a challenge in this area of research. This chapter introduces the fundamentals of heterogeneous catalysis, current industrial practices using solid catalysts, reaction steps involved in heterogeneous catalysis, conventional and advanced methods of catalyst preparation, catalyst characterization techniques, causes for catalyst deactivation, steps to avoid deactivation, and methods of catalyst reactivation. 1 aUnnikrishnan, P.1 aSrinivas, D.  uhttps://library.ncl.res.in/content/heterogeneous-catalysis