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Y Zeolite is a microporous solid used as the active component of the catalyst in the catalytic cracking process. The textural properties of a commercial USY zeolite, leached, and a series of catalysts with 25, 35, and 45% of fresh zeolite, treated at 1033 K with 20% steam for 16 h, were examined. Samples were characterized by nitrogen adsorption at 77 K; from the isotherms, micropore volume, micropore area, external surface area, and total surface area were determined using t-plots and Dubinin-Radushkevich methods. A combination of the two theories was obtained to establish a valid methodology for evaluating microporosity (ultra- and supermicropores) and mesoporosity. The results indicate that quantitative correlations exist between micropore volume calculated by t-plot and that determined by the DR model for fresh and hydrothermally treated materials.
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References
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