NIOBIUM-DOPED PHOSPHOMOLYBDIC ACID CATALYST INCLUDED IN SILICA MATRIX: STUDY OF STABILITY AND REACTIVITY USING DIFFERENT LOADS

B. COLOMBO; V. PALERMO; G. ROMANELLI; P. VAZQUEZ

LATIN AMERICAN APPLIED RESEARCH

PLAPIQUI(UNS-CONICET)

Lugar: Bahia Blanca; Año: 2023 vol. 53 p. 49 - 54

0327-0793

Abstract Heteropolyacids are used as catalystsin numerous reactions because they are inexpensive,nontoxic, have high acid strength and excellent redoxproperties. They have been used as acid catalyst indifferent ways, and numerous studies indicate that theincorporation of Nb into the structure of a solid gen-erates an increase in the acidity of the sample, both atLewis and Brönsted acid sites. Heteropolyacids havelow surface area, which makes it necessary to includethem in a support to increase the surface area and al-low their use as heterogeneous catalysts in liquidphase reactions because they are very soluble in polarsolvents. In this work, the synthesis of catalysts con-taining a niobium-doped heteropolyacid (PMoNb) in-cluded in silica at different concentrations is reported.The catalysts were characterized by ICP-MS, FT-IR,XRD, potentiometric titration, and their catalytic ac-tivity was tested in the selective oxidation of diphenylsulfide to diphenyl sulfoxide, showing excellent re-sults.