Response to comments on the paper: “Effect of organic impurities on the hydrocarbon formation via the decomposition of surface methoxy groups on acidic zeolite catalysts” by Y. Jiang, W. Wang, V.R.R. Marthala, J. Huang, B. Sulikowski, M. Hunger

A study of the acidity of SAPO-34 by solid-state NMR spectroscopy

“…In Refs. [38][39][40][41], it was ascribed to hydrogen-bonded SiOH groups. To confirm their assignments of these 1 H NMR peaks, the dehydrated SAPO-34_H sample was selected to perform the Al TRAPDOR experiment, it is observed that the peaks at 3.7 and 2.6 ppm are dephased by the 27 Al irradiation, indicating that the protons associated with these peaks are in the proximity to the Al atoms in the framework, while the signal at 1.6 ppm is depressed in the TRAPDOR difference spectrum, indicating that this proton is relatively far from Al atoms.…”

Catalytic performance of chloromethane transformation for light olefins production over SAPO-34 with different Si content

“…However, these three absorbances are not clearly present in the surface as active sites, which are responsible for the fast transformation of chloromethane and more coke deposition. The primary hydrocarbons generation during induction period of MTO process remains controversial [27,28], while olefins assembly on the unsaturated and cyclic carbonaceous reaction center is known as the dominating route in the steady state of methanol reaction. Our previous study employed hydrocarbon-pool mechanism to explain the chloromethane conversion to higher hydrocarbons [13].…”

In situ flow MAS NMR spectroscopy: State of the art and applications in heterogeneous catalysis

“…50 mg of a dehydrated catalyst powder. Such a modified 4 mm MAS NMR probe was used, for example, for studying the framework and surface sites of solid catalysts during continuous hydration/dehydration and ammoniation/deammoniation cycles by 1 H and 27 Al MAS NMR spectroscopy [12,13].…”

“…Via the quartz window and the glass fiber, the catalyst material in the sample volume of the MAS NMR rotor can be investigated by a fiber optic UV/Vis spectrometer. This MAS NMR-UV/Vis probe is suitable for experiments under continuous-flow condition [26] as well as under batch conditions [27]. In the latter case, the probe is used without an injection tube.…”

“…The hydration-and dehydration-induced changes of the framework of H-SAPO-34 has been studied by in situ 1 H and 27 Al MAS NMR spectroscopy during continuous adsorption and desorption of water. The behavior of surface sites and the coordination of aluminum atoms in the silicoaluminophosphate framework were monitored during the continuous injection (25-50 ml/min) of nitrogen loaded with water vapor (hydration) or of dry nitrogen (dehydration) into a 4 mm flow MAS NMR probe [12].…”