Biopulpaje, el futuro

- González M, J. ; Silva S., R. ; Morales, R. Departamento de Ingeniería de la Madera, Facultad de Ciencias Forestales. Universidad de ChileCon el fin de conocer las bondades y variables respuestas del biopulpaje Kraft, realizado sobre astillas de mezcla industrial de Eucalyptus (80% globulus, 20% nitens), se trató material de dicha mezcla con dos hongos de pudrición blanca ABA y ETA, durante 30 días a 25º C de temperatura y con un porcentaje de 0,3% de inóculo sobre base peso seco de madera. Una tercera muestra sin tratar fue considerada como testigo. Después del tiempo señalado, se sometieron las astillas a pulpaje Kraft, a 16% de alcali activo, 30% de sulfidez, 5/1 de relación licor/madera y 165º C de temperatura de reposo. Los rendimientos de pulpaje, variaron entre 55,8 y un 56,1% y los testigos, 52,8%. Los Kappas fueron de 13,7, 13,5 y 15,0 respectivamente. Estos resultados, para pulpas crudas de fibra corta, que son la segunda etapa del proyecto FONDEF DO2I-1086 sobre biopulpaje de Eucalyptus, presentan una perspectiva más que atractiva, para los resultados que se deberán obtener, para la implementación de biopulpaje aplicado a trozas industriales y procesos de blanqueamiento

Solvent impact assessment for the “One-Flow Functional Solvent Factory”

In the ONE-FLOW project, the concept of a “Functional Solvent Factory” is proposed, in which designer and conventional solvents are used to transform a multiphase system into a single phase system. This change of phases is alike to the creation and the disruption of compartmented spaces, which will be used for conducting multi-step reactions in a continuous flow. Due to the large availability to a great number of solvents, it is imperative to make a holistic solvent selection. Selection which must be in line with the environmental targets of the pharmaceutical industry. Herein, it is elaborated a methodology to assess common and neoteric solvents for its application in the Functional Solvent Factory. Solubility is taken as the main criterion for the assessment in the Functional Solvent Factory case; however, the solubility of a chemical in a particular solvent is not always known. Therefore, a method to circumvent the lack of solubility data, from an environmental perspective, is proposed. Afterwards, the methodology is applied to assess common solvents. The assessment considered economic and safety constraints. Decan-1-oic acid and 2-octanone were found to be the best solvents for the cascade selected. Thereafter, the environmental assessment showed that Decan-1-oic acid is the best option for the cascade. The aim of this methodology was also to include and compare ionic liquids with conventional solvents, and find the most sustainable option. Applying the methodology to compare an ionic liquid with a conventional solvent was found that the environmental impact of an ionic liquid can be lower to that of a conventional solvent. This is possible when the compound of interest has a higher solubility in the ionic liquid compared with the conventional solvent.</p

Improved constraints on WIMPs from the International Germanium Experiment IGEX

One IGEX 76Ge double-beta decay detector is currently operating in the Canfranc Underground Laboratory in a search for dark matter WIMPs, through the Ge nuclear recoil produced by the WIMP elastic scattering. A new exclusion plot, has been derived for WIMP-nucleon spin-independent interactions. To obtain this result, 40 days of data from the IGEX detector (energy threshold E \~ 4 keV), recently collected, have been analyzed. These data improve the exclusion limits derived from all the other ionization germanium detectors in the mass region from 20 GeV to 200 GeV, where a WIMP supposedly responsible for the annual modulation effect reported by the DAMA experiment would be located. The new IGEX exclusion contour enters, by the first time, the DAMA region by using only raw data, with no background discrimination, and excludes its upper left part. It is also shown that with a moderate improvement of the detector performances, the DAMA region could be fully explored.Comment: 14 pages, 8 figures, submitted to Physics Letters B (revised version after referee's comments, some figures added

First results of the ROSEBUD Dark Matter experiment

Rare Objects SEarch with Bolometers UndergrounD) is an experiment which attempts to detect low mass Weak Interacting Massive Particles (WIMPs) through their elastic scattering off Al and O nuclei. It consists of three small sapphire bolometers (of a total mass of 100 g) with NTD-Ge sensors in a dilution refrigerator operating at 20 mK in the Canfranc Underground Laboratory. We report in this paper the results of several runs (of about 10 days each) with successively improved energy thresholds, and the progressive background reduction obtained by improvement of the radiopurity of the components and subsequent modifications in the experimental assembly, including the addition of old lead shields. Mid-term plans and perspectives of the experiment are also presented.Comment: 14 pages, 8 figures, submitted to Astroparticle Physic