Caracterización por FTIR de zeolitas Co-ZSM-5.

CLARA SAUX Y LILIANA B. PIERELLA.

Gramado- Brasil.

Simposio; XX SICAT – Simpósio Ibero-Americano de Catálise.; 2006

The effect of cobalt cations incorporation into ZSM-5 zeolites was investigated by FTIR characterization technique. Cobalt was incorporated by wet impregnation technique followed by different thermal treatments: calcination and reduction. Cobalt content was varied and it was determined by atomic absorption. According to FTIR experimental data of pyridine adsorbed, all the samples present Brönsted (1550 cm-1) acidic sites. Cobalt incorporation generates new and strong Lewis sites (1452 cm-1), different from those characteristics of aluminum in the matrix (1456 cm-1). Bands related with new sites donor-acceptor were observed in Co-ZSM-5 in ~1612 cm-1 and different of those found in H-ZSM-5. The number of Lewis sites increased as Brönsted sites decreased upon introduction of cobalt.-1) acidic sites. Cobalt incorporation generates new and strong Lewis sites (1452 cm-1), different from those characteristics of aluminum in the matrix (1456 cm-1). Bands related with new sites donor-acceptor were observed in Co-ZSM-5 in ~1612 cm-1 and different of those found in H-ZSM-5. The number of Lewis sites increased as Brönsted sites decreased upon introduction of cobalt.