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In situ quantification of the active acid sites of H6P2W18O62·nH 2O heteropoly-acid through chemisorption and temperature programmed surface reaction of isopropanol
(Elsevier Science, 2004-06)
Isopropanol chemisorption and temperature programmed surface reaction analyses were used to determine the nature, amount and acid strength of the active sites of bulk WO3, monolayer supported tungsten oxide over titania ...
Simple halogen-free synthesis of aryl cinnamates using Mo-Keggin heteropoly acids as catalyst
(De Gruyter, 2012-09-12)
A convenient chlorine-free procedure for the direct esterification of cinnamic acids with phenols is described. The method does not require stoichiometric activation of the carboxyl group with thionyl chloride or condensing ...
Investigation of the thermal stability of fosfotungstic Wells-Dawson heteropoly acid through in situ Raman spectroscopy
(Elsevier, 2011-07-20)
The present investigation applies laser Raman spectroscopy under in situ conditions to obtain insights on the effect of the temperature on the molecular structure of the bulk phosphotungstic Wells-Dawson heteropoly-acid ...
Feasibility of the Redox Sulfur Recovery Process using Heteropoly Molybdophosphate
(Ecole Polytechnique de Montreal, 2016-06)
The feasibility of the removal of sulfide species using acid solutions of 12-molybdophosphoric acid was studied. The key factor in this purification process is the formation of a hydrogen-bonded structure between the ...
A green and reusable catalytic system based on silicopolyoxotungstovanadates incorporated in a polymeric material for the selective oxidation of sulfides to sulfones
(Elsevier Science, 2021-01)
Two vanadium-containing Keggin silicopolyoxotungsto compounds K5SiVW11O40 and K6SiV2W10O40 were synthesized and characterized. They were incorporated in a superporous hydrogel constitute by prop-2-enamide and propenoic ...
Sintese, caracterização e avaliação catalítica de heteropolissais lacunares e dopados com vanádio, em reações de oxidação de monoterpenos, seus álcoois e esterificação oxidativa do benzaldeídoSynthesis, characterization and catalytic evaluation of lacunar and vanadium-doped heteropoly salts in oxidation of monoterpenes, their alcohols and benzaldehyde oxidative esterification
(Universidade Federal de ViçosaAgroquímica, 2022)
Valorização dos compostos terpênicos via catálise por ácidos: Esterificação e eterificação do canfeno isomerização do óxido de alfa-pineno
(Universidade Federal de Minas GeraisUFMG, 2013-07-19)
This study aimed the development of efficient, environmentally clean and selective heterogeneous processes for the catalytic transformation of natural-renewable substrates easily available from essential oils. In order to ...