RECYCLED ZEOLITE L PREPARATION

摘要

RECYCLED ZEOLITE L PREPARATION Zeolite L is prepared in a process employing a mother liquor recycle by adjusting the alkalinity of the crystallization gel contianing the mother liquor to suppress zeolite W formation and optionally heat treating the mother liquor prior to recycle to remove zeolite W nuclei and/or crystallites. The technique is especially suitable for the formation of zeolite L with cylindrical morphology from a crystallization gel comprising (in mole ratios of oxides): K2O/SiO2 0.22 - 0.36 H2O/K2O 25 - 90 SiO2/Al2O3 6 - 15 The cylindrical Zeolite L may be used as a catalyst base in aromatization of acyclic hydrocarbons with high benzene yields being sustained over commercially feasible periods.