Fig. 2: Physical characterisation and stability of catalysts.
From: Control of zeolite microenvironment for propene synthesis from methanol
a SEM image of TaAlS-1(0.013/0.027/1), b EDX map of Ta Lɑ in TaAlS-1(0.013/0.027/1). c FTIR and d UV–vis spectra of HZSM-5(0.027/1), TaAlS-1(0.013/0.027/1) and TaS-1(0.013/1) samples. e X-band (9.4 GHz) CW EPR spectra recorded at 40 K of vacuum-sealed zeolites activated by γ-irradiation at 77 K. The spectra of Silicalite-1, TaS-1 and HZSM-5 were recorded with a microwave power of 7 mW. Simulated line shapes are shown in grey; parameters for simulation are presented in Supplementary Table 3. f Lifetime study of TaAlS-1(0.013/0.027/1) and HZSM-5(0.027/1) at 400 °C, WHSV 0.16 h−1. S(C3H6) = propene selectivity. The yield of propene on TaAlS-1 (0.013/0.027/1) remained at >50% after 54 h of continuous reaction.
