Artículos de revistas
Analysis of pulp and lignin extracted with formic acid-acetone mixture from Pinus radiata and Eucalyptus globulus woods
Registro en:
Boletin De La Sociedad Chilena De Quimica. Soc Chilena Quimica, v. 44, n. 2, n. 199, n. 207, 1999.
0366-1644
WOS:000081380600010
Autor
Freer, J
Rodriguez, J
Baeza, J
Duran, N
Urizar, S
Institución
Resumen
The aim of this work is the characterization of lignins and pulps obtained from Pinus radiata and Eucalyptus globulus woods by organosolv pulping using formic acidi acetone mixture as cooking agent. The samples were characterized by Fourier transform infrared spectroscopy (FTIR), high performance size exclusion chromatography (HPSEC) and chemical techniques. The lignins were precipitated by water from the black liquors of the wood pulping with formic acid/acetone (7:3 v/v), at temperatures of 154 degrees C and 165 degrees C for eucalyptus and pine, respectively. The FTIR spectra of the pulps indicated an effective delignification which was corroborated by the kappa numbers. The IR spectra of the lignins showed that they are highly condensed, with condensation indeces higher in pine lignins than in those extracted from eucalyptus, which increased as the pulping temperature was increased. The strong absorbance at 1720 cm(-1) in the spectra of the lignins indicated the presence of saponifiable ester groups, possibly formate. High polydispersity of the samples of lignins was observed, which was lower in the eucalyptus than in the pine lignins. The molecular masses of the formic acid-acetone lignins were relatively higher than those found for other organosolv lignins. 44 2 199 207