Figure 5.

Catalytic capacities of SA/LDH-Mg₂Al-80 in 6 successive cycles of reactions: (a) The used catalyst was refreshed by ethanol washing in the first 5 cycles and calcination in the sixth cycle; (b) The used catalyst was refreshed by water washing in the first 5 cycles and calcination in the sixth cycle. Reaction conditions: catalyst, 50 mg; benzaldehyde, 1 mmol; o-xylene, 0.1 g; nitromethane, 5 mL; time, 6 h; reaction temperature, 80 °C.