? 2022 Elsevier B.V.Pure SSZ-13 zeolite has been successfully synthesized by conversion of ZSM-5 in the absence of water for the first time. During the conversion process of ZSM-5 to SSZ-13 without seeds, ZSM-5 decomposes to produce aluminosilicate units, part of which can be reassembled into CHA structure under the action of organic template, the other part can be reorganized directly into MOR structure, which will be converted into the CHA structure by the combined action of the template and the formed SSZ-13 as crystallization time prolongs. The addition of SSZ-13 seeds avoids the generation of MOR phase and facilitates the rapid formation of SSZ-13, as well as reduces the size of the prepared samples. In the presence of 1 wt seeds, the crystallization time is shortened from 48 h to 4 h and the size of SSZ-13 is reduced from about 4 μm to about 1 μm.
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