Base catalysis hydrotalcite

Climent, M. J., Corma, A., Iborra, S. and Primo, J. Base catalysis for fine chemicals production Claisen-Schmidt condensation on zeolites and hydrotalcites for the production of chalcones and flavanones of pharmaceutical interest, J. Catal., 1995,151, 60-6. 

The Tishchenko reaction of furfural has been found to be difficult when carried out by traditional homogeneous catalysis, but excellent results for the Tishchenko reaction of furfural and 3-furaldehyde[90,91] using CaO and SrO as catalysts have been obtained. The use of other solid base catalysts such as La203, Zr02, ZnO, 7-alum in a, hydrotalcite and KOH/alumina, was unsuccessful. An investigation of the influence of the pretreatment temperature of the MgO and CaO catalysts showed that the active basic sites for this transformation are not OH groups, but rather O2 ions on the MgO surface. 

Although hydrotalcites are relahvely stable (up to circa 500 °C), they are also of potential applicahon as precursors of mixed metal oxide catalysts, for example Reference [66]. Dehydrahon-rehydration equilibria account for the switching between hydrotalcites and mixed/supported metal oxides, which is somehmes termed the memory effect [67-69]. Recent advances have seen attempts to prepare highly dispersed LDH systems, such as those dispersed within mesoporous carbon [70]. Owing to widespread interest in their application, hydrotalcite catalysts have been the subject of a number of reviews, for example References [71-75]. Other layered-based systems have also attracted attention for application in catalysis, for example Reference [76]. 

Climent, MJ Conna. A Guil-Lopez. R Iborra, S Primo. J.Solid catalysts for the production of line chemicals the use of ALPON and hydrotalcite base catalysts for the synthesis of aryl sulfones. Catalysis Letters. 1999 59. 33-38. 

Ramani, A., Chanda, B. M., Velu, S., Sivasanker, S. 1999. One-pot synthesis of coumarins. Catalysis by the solid base, calcined Mg-Al hydrotalcite. Green Chem. 1 163-165. 

Roelofs, J. C. A. A., van DiUen, A. J., de Jong, K. P. (2000). Base-catalyzed condensation of citral and acetone at low temperature using modified hydrotalcite catalysts. Catalysis Today, 60, 297-303. 

Xie, W., H. Peng, and L. Chen. 2006. Calcined Mg-Al Hydrotalcites as Solid Base Catalysts for Methanolysis of Soybean Oil. Journal of Molecular Catalysis A Chemical 246 (l-2) 24-32. 

Liu, Q., et al., 2014a. The application of Zr incorporated Zn—Al dehydrated hydrotalcites as solid base in transesterification. Catalysis Today 234, 161—166. Available at http //www. sciencedirect.com/science/article/pii/S0920586114001540 (accessed 23.04.15.). 

Reyero, I., et al., 2013. Structured catalysts based on Mg—Al hydrotalcite for the synthesis of biodiesel. Catalysis Today 216, 211—219. Available at http //www.sciencedirect.com/ science/article/pii/S0920586113002113 (accessed 15.01.15.). 

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