RT Journal Article
T1 Pitch adsorption on natural and modified talcs
A1 Tijero Cruz, Antonio
A1 Monte Lara, M. Concepción
A1 Blanco Suárez, Ángeles
A1 Negro Álvarez, Carlos
A1 Tijero Miquel, Julio
AB Talc is used traditionally for pitch control in papermaking.  The effectiveness of talcs as control agent of dissolved and colloidal pitch depends on its structural and surface characteristics of minerals. Talcs are modified by thermal and surface treatments to obtain different properties e.g specific surface, surface energy, surface charge and ratio lypophilic/hydrophilic surface.Five commercial talcs have been tested to determine its capacity to adsorb the lypophilic contaminants by experiments of adsorption isotherms. The talcs correspond to two groups of different mineralogical compositions: one with high concentration of talc and some dolomite; and the other, with medium concentrations of talc and chlorite. Colloidal dispersions of extractives were obtained by extraction of Eucalyptus globulus wood at pilot plant scale with acetone, evaporation of the solvent and reextraction with hexane to increase the selectivity of lypophillic compound extraction. The isotherms of adsorption of the pitch dispersions were carried out at 50ºC on the different talcs. The adsorption took place by a mechanism of colloidal adsorption and the results obtained were adjusted to the Langmuir equation.Results show that talc addition to bleaching waters or process waters can produce high reductions of colloidal pitch concentrations, at comparatively low doses.
PB Tappi
SN 0826-6220
YR 2009
FD 2009
LK https://hdl.handle.net/20.500.14352/51656
UL https://hdl.handle.net/20.500.14352/51656
LA eng
NO Ministerio de Ciencia e Innovación (MICINN)
DS Docta Complutense
RD 27 abr 2024