MFI MOLECULAR SIEVE CATALYST, PREPARATION METHOD THEREFOR AND USE THEREOF

Disclosed is an MFI molecular sieve, which is characterized in that each unit mass of the MFI molecular sieve comprises coexisting monoclinic and orthorhombic crystal forms of the MFI molecular sieve; in addition, the hydroxyl infrared spectrum of the MFI molecular sieve shows a characteristic peak of hydroxyl at 3400-3500 cm-1, the highest point of the characteristic peak being between 3420-3480 cm-1, the characteristic peak being centered on the highest point, and a peak area with a half-peak width of 210-240 accounting for 70% or more of the total area; the MFI molecular sieve contains the elements Si, Al and O, and does not contain the element Ti. La présente divulgation concerne un tamis moléculaire MFI, qui est caractérisé en ce que chaque masse unitaire du tamis moléculaire MFI comprend des formes cristallines monoclinique et orthorhombique coexistantes du tamis moléculaire MFI; en outre, le spectre infrarouge hydroxyle du tamis moléculaire MFI présente un pic caractéristique d'hydroxyle à 3400-3500 cm