The present work inspects the preparation of bio-composites of cassava starch with particles of eucalyptus wood through the application of a novel method of thermal compression. Bio-composites with different amounts of wood particles (5 to 30%), with particle sizes of 4 and 8 mm, were obtained. Chemical and mechanical evaluation of these samples was carried out using optical microscopy, infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and the moisture absorption effect. The effect of the amount and size of the wood particles was tested by comparison with a thermoplastic matrix sample. Results from these evaluations demonstrated that the thermocompression method produced bio-composites with a distribution of particles in the matrix that contributed to an increase in their tensile strength. This mechanical property is also enhanced by interfacial adhesion between the matrix and particles, as confirmed by SEM. Furthermore, the maximum amount of particles in the bio-composites (30%) showed the maximum resistance to moisture absorption. Temperature and time parameters contributed to the formation of diffraction patterns V H and E H as a consequence of the structural disruption of native starch. Finally, FTIR showed the chemical compatibility between the starch, glycerol, and wood particles.

Eichhornia crassipes (water hyacinth) was pulped by means of a kraft pulping process with reagent loads of 10 and 20% on a dry matter basis to determine yield, rejects, kappa number, and ash. Fiber classification, brightness, opacity, and viscosity were measured in the brown pulp. Bleaching was performed by means of an O1O2D1(PO)D2HD3 sequence. Yield, kappa number, pH, ash, brightness, opacity, and viscosity were evaluated in the bleached pulp. Finally, a microanalysis of inorganic elements was carried out in both the bleached and unbleached pulp ash. The highest kraft pulp yield was 26.4%, with a 10% reagent load at 120 °C and 30 minutes cooking. It was determined that E. crassipes cellulosic pulp contains large amounts of fines. Results of the bleaching sequence indicate low brightness (58.0 %) and low viscosity (6.43 cP). The most abundant inorganic elements in the ash of both bleached and unbleached pulp were Ca, Mg, P, and Si. These results suggest that E. crassipes biomass might complement cellulosic fibers in pulping processes of low yield, such as the wood fibers used to produce handmade paper.

El objetivo de esta investigación fue incrementar el rendimiento y la calidad de la pulpa generada a partir de astilla industrial de Pinus pseudostrobus L. Se trabajó con la astilla industrial de la madera de Pinus pseudostrobus L. de la empresa SCRIBE planta Morelia, Michoacán, México. Las temperaturas empleadas fueron 165 °C y 170 °C, los tiempos de cocción 40 minutos y 80 minutos, cargas de reactivos de 18% y 22%. Las variables de respuesta fueron: rendimiento, número de kappa, rechazos y álcali residual de acuerdo con las normas TAPPI. Los resultados se analizaron aplicando un diseño experimental factorial. El rendimiento varió de 33% a 52%; el número de kappa de 11 a 40; los rechazos de 3.4% a 25.4% y el álcali residual de 3.1 g/L a 11 g/L. La maximización del rendimiento (54.8%) se obtuvo a una temperatura de 162 °C, tiempo de cocción de 40 minutos y carga de reactivos de 23%. La minimización de la variable número de kappa (11.2), se obtuvo a una temperatura de 166 °C, tiempo de cocción de 26 minutos y carga de reactivos de 19%. La minimización de los rechazos se presentó a una temperatura de 162 °C, 26 minutos de cocción y carga de reactivos de 19%. Por último, la minimización del álcali residual (4.9 g/L) se presentó a una temperatura de 169.18 °C, tiempo de cocción de 60.14 minutos y carga de reactivos de 20%. Las condiciones de operación en el proceso de cocción proporcionan un rendimiento de 50% con respecto al porcentaje de astilla inicial utilizada y un número de kappa de 15.8 menor en comparación con resultados de pulpas de especies de pino publicados.