A new microporous zeolitic silicoborate (ITQ-52) with interconnected small and medium pores

A new zeolite (named as ITQ-52) having large cavities and small and medium channels has been synthesized. This was achieved by using a new family of amino-phosphonium cations as organic structure directing agents (OSDA). These cations contain P−C and P−N bonds, and therefore they lie between previously reported P-containing OSDA, such as tetraalkylphosphonium and phosphazenes. In this study, it has been found that 1,4- butanediylbis[tris(dimethylamino)]phosphonium dication is a very efficient OSDA for crystallization of several zeolites, and in some particular conditions, the new zeolite ITQ-52 was synthesized as a pure phase. The structure of ITQ-52 has been solved using high-resolution synchrotron X-ray powder diffraction data of the calcined solid. This new zeolite crystallizes in the space group I2/m, with cell parameters a = 17.511 Å, b = 17.907 Å, c = 12.367 Å, and β = 90.22°. The topology of ITQ-52 can be described as a replication of a composite building unit with ring notation [435461] that gives rise to the formation of an interconnected 8R and 10R channel system.We thank financial support by the Spanish Government (MAT2012-38567-C02-01, MAT2012-38567-C02-02, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267). R.S. acknowledges to UPV for a FPI predoctoral fellowship. Authors thank ALBA Light Source for beam allocation at beamline MSPD. We thank G. Sastre and J. A. Vidal for computational calculations and MAS NMR experiments, respectively.Simancas Coloma, R.; Jorda Moret, JL.; Rey Garcia, F.; Corma Canós, A.; Cantin Sanz, A.; Peral, I.; Popescu, C. (2014). A new microporous zeolitic silicoborate (ITQ-52) with interconnected small and medium pores. Journal of the American Chemical Society. 136(9):3342-3345. doi:10.1021/ja411915c33423345136