Active sites on ZSM—5 zeolites for toluene disproportionation

Methane dehydroaromatization over Mo/HZSM-5 catalysts in the absence of oxygen: effects of silanation in HZSM-5 zeolite

“…2(a)). It is generally accepted that, the peak at low temperature (556 K) is associated with the physisorbed ammonia [39], while the one at 759 K has been attributed to the ammonia adsorbed on the strong acid sites [40][41][42]. The adscription of the peak at moderate temperature in the NH 3 -TPD profiles is still uncertain.…”

Low temperature catalytic combustion of 1,2-dichlorobenzene over CeO2–TiO2 mixed oxide catalysts

“…NH3-TPD profiles can be deconvoluted by the Gauss curve fitting method [38] into three peaks (noted as a, b and c, respectively) with the centers at 217-255 o C, 272-327 o C and 351-403 o C, corresponding to ammonia desorbed from weak, moderate and strong acidic sites. Normally, the area of a specific peak corresponds to the amount of ammonia that desorbs from the sample, and could be taken as a standard to quantify the acidity of the sample [39]. With the presence of Ti, "a" peak and "b" peak shift to high temperature.…”

Reductive Amination of Triacetoneamine with n-Butylamine Over Cu–Cr–La/γ-Al2O3

“…The two desorption peaks at the lower temperature (229°C) and the higher temperature (470-529°C) correspond to the weak and strong acid sites on the catalyst surfaces, respectively [26]. Normally, the area of a specific peak can be used to estimate the amount of ammonia desorbed from the sample, and can be taken as a standard to quantify the acidity of the sample [27,28]. The peak areas for the two temperature peaks are listed in Table 3.…”