Title: Iron exchanged natural mordenite: UV-Vis diffuse reflectance and Mössbauer spectroscopy characterisation

Authors: Daria Tito-Ferro; Inocente Rodríguez-Iznaga; Beatríz Concepción-Rosabal; Gloria Berlier; Fernando Chávez-Rivas; Arbelio Penton-Madrigal; Felipe F. Castillón-Barraza; Vitalii Petranovskii

Addresses: Departamento de Investigaciones, Centro Nacional de Electromagnetismo Aplicado (CNEA), Universidad de Oriente, Ave. Las Américas s/n, Santiago de Cuba, CP 90400, Cuba ' Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G. s/n, La Habana CP 10400, Cuba ' Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Zapata y G. s/n, La Habana CP 10400, Cuba ' Dipartimento di Chimica and NIS Centre of Excellence, Università di Torino, Italy ' Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Mexico, C.P. 07738, México, D.F. ' Facultad de Física, Universidad de La Habana, La Habana CP 10400, Cuba ' Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología, Km. 107 Carretera Tijuana a Ensenada, C.P. 22860 Ensenada, Baja California, Mexico ' Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología, Km. 107 Carretera Tijuana a Ensenada, C.P. 22860 Ensenada, Baja California, Mexico

Abstract: Purified natural mordenite (ZP) from Palmarito de Cauto deposit, Cuba, was modified with Fe²⁺ and Fe³⁺cations through ion-exchange in acid medium and characterised by UV-Vis diffuse reflectance, FTIR and Mössbauer spectroscopies. Fe²⁺ exchange is less favoured than Fe³⁺ exchange, which may be due to higher Fe³⁺ valence. In the Fe²⁺ exchanged samples, Fe²⁺ZP, all incorporated Fe²⁺ is found in octahedral coordination and it should be mainly in cationic extra-framework positions inside mordenite channels as a charge compensating cation. In the case of the Fe³⁺ exchanged samples, Fe³⁺ZP, the incorporated Fe³⁺ is present in both octahedral and tetrahedral coordination and it can be in both cationic extra-frameworks positions as a charge compensating cation and in form of oxy-hydroxides originated by Fe³⁺ hydrolysis.

Keywords: zeolite; natural mordenite; iron exchange; UV-Vis diffuse reflectance; FTIR; Mossbauer spectroscopy.

DOI: 10.1504/IJNT.2016.074528

International Journal of Nanotechnology, 2016 Vol.13 No.1/2/3, pp.112 - 125

Published online: 04 Feb 2016 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article