02200nas a2200289   4500008004100000022001400041245008000055210006900135260007300204300001200277490000800289520115000297653003401447653001401481653001801495653003201513653003901545653002801584653002901612653002601641653004201667100003801709700001901747700001701766700001801783856010901801       2006                        eng d  a0926-860X00aHydrophobic, solid acid catalysts for production of biofuels and lubricants0 aHydrophobic solid acid catalysts for production of biofuels and   aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcNOV  a148-1590 v3143 a<p>A novel application of Fe-Zn double-metal cyanide (DMC) complexes as solid catalysts in the preparation of fatty acid alkyl esters (biodiesel/biolubricants) from vegetable oils is reported. The catalysts are hydrophobic (no H2O adsorption at reaction temperatures) and contain only Lewis acidic sites (NH3 and pyridine adsorption). Bronsted acid sites are absent (absence of 1546 and 1639 cm(-1) bands on adsorption of pyridine). Basic sites are also absent (no CO2 adsorption). Unlike the homogeneous or other solid catalysts (like ZnO-Al2O3, for example), the Fe-Zn, DMC catalysts are highly active even for the simultaneous transesterification of triglycerides and esterification of the free fatty acids (FFA) present in unrefined and waste cooking oils as well as non-edible oils. They are also tolerant of water, probably, due to their surface hydrophobicity. A relationship between the transesterification activity and the concentration of strong Lewis acid sites has been observed. Coordinatively unsaturated Zn2+ ions in the structure of the Fe-Zn complex are the probable active sites. (c) 2006 Elsevier B.V. All rights reserved.</p>10aalcoholysis of vegetable oils10aBiodiesel10aBiolubricants10adouble-metal cyanides (DMC)10aesterification of free fatty acids10afatty acid alkyl esters10afatty acid methyl esters10asolid Fe-Zn catalysts10atransesterification of vegetable oils1 aSreeprasanth, Pulinthanathu, Sree1 aSrivastava, R.1 aSrinivas, D.1 aRatnasamy, P.  uhttps://library.ncl.res.in/content/hydrophobic-solid-acid-catalysts-production-biofuels-and-lubricants-0