02282nas a2200253   4500008004100000022001400041245012200055210006900177260007100246300001200317490000800329520134200337653003501679653001901714653003401733653002201767653001801789100001601807700001101823700002501834700002301859700001601882856013001898       2011                        eng d  a0920-586100aCeria-zirconia mixed oxides as thermal resistant catalysts for the decomposition of nitrous oxide at high temperature0 aCeriazirconia mixed oxides as thermal resistant catalysts for th  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbFrench GDFSUEZ CocNOV  a453-4570 v1763 a<p>This present study deals with the development of thermally stable catalysts for the decomposition of nitrous oxide. There is actually a growing interest to minimise the emissions of nitrous oxide (N(2)O) as side-product from nitric acid plants due to a global warming potential of approximately 300 times higher than that of CO(2). Different strategies have already been implemented at industrial scale but they are still suffering from significant drawbacks essentially associated to a poor selectivity and sometimes a short lifetime in particular when the catalytic process is inserted downstream the ammonia burner. In those critical conditions, with high residual temperature of similar to 900 degrees C, significant surface and bulk reconstructions take place and then lead to drastic losses of specific surface area and related catalytic performances in the decomposition of N(2)O to N(2). Previous investigations performed in our laboratory revealed the potentiality of zirconia particularly after yttria incorporation [Appl. Catal. B 62 (2005) 236]. Novel developments of more stable ceria-zirconia based catalysts are reported in this study. Further stabilisation and enhancement in activity have been discussed on the basis of oxygen mobility related to structural properties. (C) 2010 Elsevier B.V. All rights reserved.</p>10aCeria-zirconia based catalysts10aGreenhouse gas10aN(2)O catalytic decomposition10aNitric acid plant10aNitrous oxide1 aEsteves, P.1 aWu, Y.1 aDujardin, Christophe1 aDongare, Mohan, K.1 aGranger, P.  uhttps://library.ncl.res.in/content/ceria-zirconia-mixed-oxides-thermal-resistant-catalysts-decomposition-nitrous-oxide-high-001998nas a2200181   4500008004100000022001400041245009600055210006900151260011000220300001400330490000700344520123700351100002501588700002501613700002301638700002801661856012701689       2013                        eng d  a1463-926200aCatalytic dehydration of lactic acid to acrylic acid using calcium hydroxyapatite catalysts0 aCatalytic dehydration of lactic acid to acrylic acid using calci  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcFEB  a1211-12170 v153 a<p>A series of calcium hydroxyapatite (HAP) catalysts were synthesised with a Ca/P ratio ranging from 1.3 to 1.89 by a co-precipitation method that involved changing the pH of the calcium and phosphorous precursors. The physicochemical characterization by XRD, SEM, BET surface area and CO2 and NH3-TPD techniques confirmed the hydroxyapatite formation. These HAP catalysts were used for the vapour phase dehydration of lactic acid to acrylic acid. The HAP catalyst with a Ca/P ratio of 1.3 was found to be the most efficient catalyst among the synthesised series, which gave 100% conversion of lactic acid and 60% selectivity towards acrylic acid at 375 degrees C when a 50% (w/w) aqueous solution of lactic acid was used. The higher selectivity towards acrylic acid has been correlated to the increased acidity and reduced basicity of the HAP catalyst with a Ca/P ratio of 1.3 compared to the other HAP catalysts. The catalyst was found to be very stable and no deactivation was observed even after 300 h of reaction time. In situ FTIR studies were performed for understanding the mechanistic aspects and showed the formation of calcium lactate as an intermediate species during the dehydration of lactic acid to acrylic acid.</p>1 aGhantani, Vidhya, C.1 aLomate, Samadhan, T.1 aDongare, Mohan, K.1 aUmbarkar, Shubhangi, B.  uhttps://library.ncl.res.in/content/catalytic-dehydration-lactic-acid-acrylic-acid-using-calcium-hydroxyapatite-catalysts-0