Layer-Like Zeolite X as Catalyst in a Knoevenagel Condensation: The Effect of Different Preparation Pathways and Cation Exchange

This study is dedicated to the comparative investigation of catalytic activity layer-like Faujasite-type (FAU) zeolite X obtained from three different synthesis routes (additive-free route, Li2CO3 and TPOAC route) in a liquid-phase Knoevenagel condensation benzaldehyde ethyl cyanoacetate trans-α-cyanocinnamate. It shown that charge-balancing cations (Na+ K+) morphological properties have strong influence on apparent reaction rate degree conversion. The highest initial could be found for synthesised by additive-free route potassium form. In most cases, potassium-exchanged zeolites enabled higher maximum conversions rates compared catalysts sodium However, very thin crystal plates (below 100 nm thickness), similar those presence TPOAC, did not withstand multiple aqueous ion exchange procedure, with remaining coarse crystals facilitating less enhancement activity.