ELATIONSHIP BETWEEN THE CHARACTERISTICS OF MICROFIBRILLATED CELLULOSE (MFC), PULPS, AND RAW MATERIALS

GONZALEZ, R.; AGUERRE, Y.; PEREIRA, M.; VALLEJOS, M.E.; FELISSIA, F.E.; AREA, M.C.

Córdoba

Workshop; International Workshop on Biorefinery of Lignocellulosic Materials - IWBLCM 2019; 2019

Universidad de Córdoba

The aim of this study was to verify the existence of relationships between the characteristicsof MFC and those of the different pulps from which they were obtained. Ten pulps were used, namely, an unbleached chemimechanical pulp from mixed planted hardwoods; pineunbleached kraft pulp, pine and eucalyptus ECF bleached kraft pulps, a sugarcane bagasseTCF bleached soda-anthraquinone chemical pulp, and three organosolv pulps from pinesawdust. The mechanical treatment involved PFI refining (100,000 revolutions, 10%consistency) followed by homogenization (PANDA homogenizer, 15 passes, 700 bar, 1%consistency). The energy consumption in the production of the different MFC was evaluated. Fiber and MFC dimensions were determined by a Fiber Analyzer and a Microtrac, respectively. The degree of fibrillation was estimated by the centrifugation yield (ratio between dry weight and wet weight of the fibrous sediment after centrifugation at 3000 rpm for 15 min) and by dynamic viscosity (Brookfield viscometer). In addition, the transmittance (at 800 nm) and the degree of polymerization (DP) by intrinsic viscosity in cupriethylenediamine were evaluated. The energy consumption was 121 kW-h / kg (odp) for the chemimechanical pulp and varied from 136 to 91 kW-h / kg (odp) for chemical pulps. MFC dimensions were about 1 micron width by several microns in length. The intrinsic viscosities in water varied from 1419 in eucalyptus pulp to 590 in bagasse chemical pulp. The length of MFC showed inverse correlations with the fiber length and with the fiber width. DP only correlated with fibrillation energy. The centrifugation yield was a good indicator of the fibrillation time.