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The distribution of aluminum atoms within zeolite frameworks, both in terms of local arrangement and tetrahedral-site (T-site) location, determines their structural, ion-exchange, and catalytic properties. Here, we study different methods for interzeolite transformation of faujasite (FAU) zeolites into chabazite (CHA) zeolites, and their effects on the framework aluminum distribution in CHA. Previous literature reports have demonstrated that the common structural building units, such as the double six-member ring (D6R) building units in FAU and CHA, are an important structural feature that enables the conversion of one zeolite topology into another. Here, we employ the highly symmetric, single T-site zeolites (FAU and CHA) to study framework Al arrangement independently of T-site location effects that are also present in lower-symmetry zeolite frameworks. Two hydroxide mediated synthesis procedures were studied, one utilizing the organic-structure directing agent (OSDA) N,N,N-trimethyl-1-adamantylammonium
cation, and the other utilizing only inorganic alkali cations as structure-directing agents. Both procedures have previously been reported to facilitate the interzeolite conversion of FAU into CHA, however neither has been studied to understand how local Al arrangements are influenced by the interconversion synthesis route. Powder X-ray diffraction patterns (XRD) and argon adsorption isotherms are used to probe changes in zeolite topology during the conversion of FAU to CHA. Elemental analysis with atomic absorption spectroscopy (AAS) was used to characterize the total Al content of each zeolite sample, and temperature programed desorption (TPD) of ammonia was used to quantify the total number of Brønsted acid sites. Aqueous-phase divalent cobalt (Co²⁺) ion-exchange isotherms were measured for each topology, and saturation Co²⁺ uptakes on each sample were used to determine the total number of paired Al sites (Al-O-(Si-O)_x-Al; x = 1,2 paired and x ≥ 3 isolated) in FAU and CHA. Diffuse reflectance UV-Vis spectroscopy (DRUV-VIS) was used to ensure that no cobalt oxides were present and only bare Co²⁺ was exchanged onto the zeolite. We discuss how changing the conditions used for interzeolite conversion can lead to differences in the framework Al distribution in the CHA product zeolites compared to each other and the parent FAU zeolites.