Facile and fast synthesis of highly active Lewis acid MWW zeolite from pure silica ITQ-1†
A facile hydrothermal etching–healing strategy is proposed to fabricate a Sn-MWW zeolite based on a pure silica ITQ-1 precursor, which avoids using any supporting agents and additives, such as B3+ and Na+. Thus, post-synthetic acid treatments for the removal of such additives to ensure catalytic performance are not required, which is a great improvement to the conventional Sn-MWW synthetic route. Moreover, low organic structure-directing agent (SDA) consumption and rapid growth make this approach practically attractive. The growth mechanism study reveals the crucial etching and healing dual functional role of the SDA, which leads to successful Sn introduction. The obtained Sn-MWW exhibits excellent glucose isomerization catalytic performance owing to the “clean” (without the side effect of additives) and well-defined Sn sites.