A Complex Zeolite Containing Multiple Ring Sizes in a Single Channel: One-Dimensional Zeolite UZM-55.

Zeolites are porous aluminosilicate materials utilized in a variety of sorption, separation, and catalytic applications. The oil refining industry in particular has seen a number of significant advances due to the introduction of new technologies enabled by new zeolites. Of particular importance are zeolites with 10- or 12-membered ring pores, resulting in pore shapes and sizes appropriate for the interaction with small hydrocarbon molecules. Here, the synthesis of a new zeolite UZM-55 is reported and the idealized structure thereof is presented. The most complex structure solved to date, UZM-55 possesses a large triclinic unit cell containing 52 T-sites. The material uniquely contains both 10- and 12-membered ring pores in a single, undulating one-dimensional channel, the first example in a zeolitic material of multiple delimiting rings in a single channel. This discovery opens new opportunities in shape-selective adsorption and catalysis. Demonstrated here is the unique adsorption behavior of UZM-55, shown both experimentally and computationally to adsorb one nonane molecule per unit cell in a linear conformation.