RT Journal Article
T1 Ammonia and water in zeolites: Effect of aluminum distribution on the heat of adsorption
A1 Zhakisheva, Botagoz
A1 Gutiérrez Sevillano, Juan José
A1 Calero, Sofía
K1 Simulación Molecular
K1 Monte Carlo
K1 Zeolitas
K1 Ammonia
AB We have investigated MOR, MFI, and FAU zeolites to acquire a better understanding of the aluminum T-position effect on the heat of adsorption of ammonia and water at a microscopic level. We performed Monte Carlo simulations using RASPA code to obtain the heats of adsorption of water and ammonia in zeolites with one Al-substitution. We show that the values of heats of adsorption of water and ammonia on MOR do not vary much for the T1, T2, and T4 positions being around 41 kJ/mol and 31 kJ/mol respectively. However, the T3 position shows a noticeable variation for both molecules. When aluminum is in the T3 position ammonia with zeolite have the strongest interaction, inversely water and zeolite have the weakest interaction compared to the other T-sites. MFI-type zeolite is also sensitive in terms of Al-position, and more significantly in the case of ammonia adsorption. In MFI all favorable/unfavorable for water T-sites of MFI were also favorable/unfavorable for ammonia respectively. The heats of adsorption of ammonia and water as a function of the position of aluminum substitution in FAU (super-cage, sodalite cage, or hexagonal prism) have almost constant values with 40.5 kJ/mol for water and 28.3 kJ/mol for ammonia. Thus, FAU zeolite has been shown to be insensitive with regard to T-positions which are crystallographically identical in a highly symmetric spherical cage topology.
PB Elsevier
YR 2023
FD 2023
LK https://hdl.handle.net/10433/25818
UL https://hdl.handle.net/10433/25818
LA en
NO Separation and Purification Technology Volume 306, Part A, 1 February 2023, 122564
NO Ministerio de Ciencia e Inno­vacion (IJC2018-038162-I)
NO Universidad Pablo de Olavide. Departamento de Sistemas Físicos, Químicos y Naturales
DS RIO
RD Apr 28, 2026