aThe unit of the acid amount is mmol
g−1.
The pyridine FT-IR results are shown in Fig. 10, both Brønsted (B) and
Lewis (L) acid sites are present on all ZSM-5 samples’ surface,
corresponding to the stretching bands at around 1540 and 1450
cm−1, respectively [9,46,47]. The peaks near 1490
cm −1 can be attributed to the pyridine species
interacting with B and L acid sites [48]. The ZSM-5 samples prepared
via enhancing micromixing no matter in the premixing or crystallization
process exhibit a larger amount of B and L acid sites at 200 ℃ (Table
4). For all ZSM-5 samples, compared to B acid sites, the amount of L
acid sites decreases obviously with the increasing temperature (Table
S1), indicating that the strength of L acid sites is weaker than B acid
sites [48].