Role of formaldehyde in promoting aromatic selectivity during methanol conversion over gallium-modified zeolites.

ABSTRACT: Gallium-modified HZSM-5 zeolites are known to increase aromatic selectivity in methanol conversion. However, there are still disputes about the exact active sites and the aromatic formation mechanisms over Ga-modified zeolites. In this work, in situ synchrotron radiation photoionization mass spectrometry (SR-PIMS) experiments were carried out to study the behaviors of intermediates and products during methanol conversion over Ga-modified HZSM-5. The increased formaldehyde (HCHO) yield over Ga-modified HZSM-5 was found to play a key role in the increase in aromatic yields. More HCHO was deemed to be generated from the direct dehydrogenation of methanol, and Ga₂O₃ in Ga-modified HZSM-5 was found to be the active phase. The larger increase in aromatic production over Ga-

SUBMITTER: Wen W 

PROVIDER: S-EPMC9814038 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature