fig5

Figure 5. Acid amount on BAS measured by (A) Py and external surface BAS measured by (B) 2,4,6-TTBPy and (C) THA of the three HY zeolites. BAS: Brønsted acid sites; Py: pyridine; 2,4,6-TTBPy: 2,4,6-tri-tert-butylpyridine; THA: trihexylamine.