National Biofuels Energy Laboratory Copyright (c) 2013 Wayne State University All rights reserved. http://digitalcommons.wayne.edu/bio_fuel Recent documents in National Biofuels Energy Laboratory en-us Wed, 23 Jan 2013 23:05:45 PST 3600 Effects of Preparative Parameters on the Structure and Performance of Ca-La Metal Oxide Catalysts for Oil Transesterification http://digitalcommons.wayne.edu/bio_fuel/2 http://digitalcommons.wayne.edu/bio_fuel/2 Mon, 08 Mar 2010 12:10:36 PST The effects of preparative parameters on the surface basicity, composition, and transesterification activities of several Ca-La metal oxide catalysts were investigated. Four different preparation methods: ammonia-ethanol-carbon dioxide precipitation, physical mixing, impregnation, and co-precipitation, were studied. It was found that the ammonia-ethanol-carbon dioxide precipitation method resulted in the highest BET specific surface area, base strength and base site concentration. Moreover, catalyst surface composition and basicity are a function of calcination temperature, precipitants, pH, and molar ratio of Ca to La in precursor solution, and storage conditions. XRD, XPS, basicity and BET tests revealed that catalyst structure and dispersion of Ca species strongly influenced the catalyst activity. High surface concentration of Ca species, strong base strength and high concentration of base sites, and high specific surface area are characteristics of an active transesterification catalyst.

]]> Shuli Yan et al. The Effect of Sodium on the Catalytic Activity of ZnO-Al2O3/ZSM-5 and SnO-Al2O3/ZSM-5 for the Transesterification of Vegetable Oil with Methanol http://digitalcommons.wayne.edu/bio_fuel/1 http://digitalcommons.wayne.edu/bio_fuel/1 Fri, 05 Mar 2010 10:47:23 PST In order to elucidate the effect of sodium on the activity of ZSM-5 supported metal oxides catalysts (ZnO-Al2O3/ZSM-5 and SnO-Al2O3/ZSM-5) for the transesterification of soybean oil with methanol, ZSM-5 supported metal oxides were prepared with and without sodium hydroxide by impregnation. The metal compositions of the ZSM-5 supported metal oxide catalysts and the metal concentrations dissolved from the catalysts to the methylester phase were measured by SEM-EDS and inductive coupled plasma spectroscopy, respectively. The catalytic activity of ZnO-Al2O3/ZSM-5 and SnO-Al2O3/ZSM-5 containing sodium did not originate from surface metal oxides sites, but from surface sodium sites or dissolved sodium leached from the catalyst surface.

]]> Manhoe Kim et al.