Kinetics of vanillin oxidation

• Tipo: Artigo em Revista Científica Internacional
• Data: 1996

Autores

Fargues, C (Autor) Outra; Mathias, A (Autor) Outra; Silva, J (Autor) Outra; Alírio Rodrigues (Autor) FEUP

Revista

Título: Chemical Engineering and Technology

Vol. 19

Páginas: 127-136

ISSN: 0930-7516

Editora: Wiley-Blackwell

Indexação

ISI Web of Knowledge - 16 Citações

Scopus - 16 Citações

Outras Informações

ID Authenticus: P-001-EFT

DOI: 10.1002/ceat.270190206

Abstract (EN): Vanillin can be produced by oxidation of kraft lignin, with air, in alkaline medium. The optimal conditions for vanillin production strongly depend on pH and temperature. This paper addresses the effect of temperature and pH on vanillin degradation by oxidation. Experiments were carried out in a wide range of vanillin concentration, oxygen partial pressure, temperature and pH. Simple models are proposed to explain the observed rate of vanillin consumption under conditions of high alkalinity (pH > 12) and lower alkalinity (pH < 12). At pH > 12, the reaction rate of vanillin oxidation is first order in dissolved oxygen concentration [O-2] and in vanillin concentration [C], i.e., (-r(C))proportional to[O-2][C]; at pH < 12, the rate is zero order in oxygen concentration and second order in vanillin concentration, i.e., (-r(C)>proportional to f(pH)[C](2).

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 10