Calcined Mg–Al hydrotalcites as solid base catalysts for methanolysis of soybean oil

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

“…In order to minimize or avoid problems associated with the homogeneous catalytic process, attempts have been made to develop heterogeneous catalyst systems [2][3][4][5][6][7]. The catalytic activity of the heterogeneous base catalyst, in the transesterification of soybean oil, shows a striking correlation with basic strength [5,[8][9][10].…”

“…The catalytic activity of the heterogeneous base catalyst, in the transesterification of soybean oil, shows a striking correlation with basic strength [5,[8][9][10]. Thus, most heterogeneous catalysts for biodiesel production contain alkali or alkali earth cations [4,5,8,9,[11][12][13][14][15][16][17][18][19].…”

“…Several studies reported that Mg-Al hydrotalcites [4,5,21] and metal oxides (Al2O3-SnO, Al2O3-ZnO) [22] were active for the transesterification of vegetable oils with methanol at a relatively low reaction temperature. Although sodium hydroxide or sodium carbonate compounds were used in these catalyst preparations, the catalytic activity and deactivation behavior of the metal oxide catalysts were reported as originating from metal oxides (Al2O3-SnO, Al2O3-ZnO) or Mg-Al hydrotalcites sites [4,5,21,22]. As a result, there are conflicting reports of the catalytic activity of the metal oxides catalysts at low temperature for transesterification of vegetable oil and methanol.…”

Ammonium Sorption onto Polymeric Adsorbing Material from Corn Stalks Oxidized and Loaded with Magnesium

“…Freshly produced biochars typically have very low ability to adsorb ammonium (Zhang et al 2011). Over time, the biochar surfaces are oxidized, and cation retention increases to greater levels (Cantrell et al 2005;Xie et al 2006). Oxidation may also be achieved intentionally as part of an effort to improve nutrient retention by biochars.…”

Impact of Organic Interlayer Anions in Hydrotalcite Precursor on the Catalytic Activity of Hydrotalcite‐Derived Mixed Oxides

“…[5][6][7][8][9] The attention hydrotalcite-derived mixed oxides have gained is mainly due to the fact that their catalytic properties can be set and adjusted by the composition of the hydrotalcite precursors during synthesis. Parameters influencing the catalytic properties of hydrotalcite-derived mixed oxides are the nature and ratio of cations within the cationic layers and the nature of anions in the interlayer region of the hydrotalcite precursor as well as the temperature of thermal decomposition, [6,[10][11][12][13] which affects the basic site density. [14] The influence of the composition of brucite-type layers in hydrotalcite precursors on the catalytic activity of derived mixed oxides has already been investigated.…”