Sulfated tin oxide with macro- and mesopores controlled using an integrated sol-gel and surfactant template route

Autor(es)

Alves-Rosa, Marinalva A. ^[1] ; Vasconcellos, Jonatas Z. ^[1] ; Vieira, Luiz H. ^[2] ; Santilli, V, Celso ; Pulcinelli, Sandra H. ^[3]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ UNESP, Inst Chem, POB 355, BR-14800060 Araraquara, SP - Brazil

^[2] Univ Sao Paulo, Sao Carlos Inst Chem, Av Trabalhador Sao Carlense 400, BR-13560970 Sao Carlos, SP - Brazil

^[3] Santilli, Celso, V, Sao Paulo State Univ UNESP, Inst Chem, POB 355, BR-14800060 Araraquara, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS; v. 583, DEC 20 2019.
• Citações Web of Science: 0

Resumo

Sulfated fin oxide was synthesized by a sol-gel process and pores were formed in the ceramic powders using Pluronic F-127 as a soft template. Sulfate ions linked to the fin oxide promoted the formation of acid sites on the particle surfaces. After calcination, the sulfate ions remained on the oxide particles as uni- and bidentate complexes, so changes in the fin atom coordination numbers at the second shells could be observed by X-ray absorption spectroscopy. The fin oxides showed a cassiterite nanocrystalline structure consisting of aggregates of spherical particles, with crystallite size of around 8 nm, radius of gyration similar to 3.7 nm, and mean particle size between 7 and 10 nm, according to X-ray diffraction and small angle X-ray scattering measurements, together with the use of transmission electron microscopy images. The use of Pluronic F-127 as a template for the pores resulted in the formation of meso- and macropores sized around 7.5 nm and 60 mu m respectively, surface area of 128 m(2) g(-1) and porosities of 71%, after calcination at 500 degrees C. The porous sulfated fin oxide was used to catalyze the isopropanol dehydration reaction, with production of propene. The catalytic activity and the temperature-programmed desorption of ammonia confirmed the presence of acid sites on the surface, suggesting that this material could be employed as a heterogeneous catalyst in acid-catalyzed reactions. (AU)

• Processo FAPESP: 14/50948-3 - INCT 2014: tecnologias ecoeficientes avançadas em produtos cimentícios
• Beneficiário: Vanderley Moacyr John
• Modalidade de apoio: Auxílio à Pesquisa - Temático