Synthesis of liquid menthol by hydrogenation of dementholized peppermint oil over Ni catalysts

• Autor(a) principal: Manuale,Debora L.
• Data de Publicação: 2010
• Outros Autores: Betti,Carolina, Marchi,Alberto J., Yori,Juan C., Romeo,Eva
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Química Nova (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422010000600002
• topic: selective hydrogenation; liquid menthol; Ni catalysts

Hydrogenation of (-)-menthone and (+)-isomenthone was studied at 2.7 MPa and 100 ºC. The objective was to produce a liquid menthol mixture rich in (-)-menthol from dementholized peppermint oil. Ni-based catalysts were tested and compared for this reaction: a) 6 and 12% Ni dispersed into a nonstoichiometric magnesium aluminate (Ni-Mg-Al) with spinel structure; b) Ni-Raney catalyst. Both types of catalysts were active for (-)-menthone and (+)-isomenthone hydrogenation. Lower conversion but higher selectivity to (-)-menthol was obtained with Ni-Mg-Al catalysts. However, they rapidly lost their activity. Instead Ni-Raney catalysts kept its original activity even after several hydrogenation runs.