Fábio Akira Mori

Utilização de eucaliptos e de madeiras nativas no armazenamento da aguardente de cana-de-açúcar

The aim of this work was to evaluate different species of Eucalyptus and of native wood to make barrels for storage of sugar cane spirit. It was studied the chemical, anatomical and physical properties of the woods and made physical-chemical analyses of the sugar cane spirit storage during twelve months. The barrels made with wood of Eucalyptus presented little permeabilidade to liquids and a low dimensional estability, provoking discard of great part of them. The chemical composition of the different Eucalyptus wood showed constant polissacarydes and lignina contents but differing among extractives levels, that were higher than the oak wood. The composition of the sugar cane spirit stored in these kind of wood showed pattern according to the Brazilian law, indicating their potential use as barrels for the storage of sugar cane spirit. The native wood, also showed low dimensional instability with no leaking, constant polyssacarydes and lignina contents and higher extractive levels than oak wood. The sugar cane spirit composition after storage was also according to the law.

Efeito da incorporação de casca de café nas propriedades físico-mecânicas de painéis aglomerados de Eucalyptus urophylla S.T. Blake

The objective of this study was to evaluate the influence of the incorporation of Coffee husks in the production of particleboard with Eucalyptus urophylla S.T. Blake. The panels were produced incorporating 25%, 50%, and 75% of Coffee husks at three levels of resin phenol-formaldehyde (6, 9 and 12%) and 1% of paraffin. The nominal density of the panels was 0.7 g/cm3 and the cycle of pressing consisted in a pressure of 3.92 MPa under a temperature of 180°C for 8 minutes. By the results it was possible to observe that the physical properties of the particleboard have a linear relationship decreasing with the increase in the level of resin, and increasing with the increase in the percentage of coffee husks, showing higher values of water absorption and thickness swelling. The mechanical properties show a linear relationship growing with the increase of resin level, and decreasing with a reduction the percentage of coffee husk association. The way that the search was conducted, the incorporation of the Coffee husks harms the quality of the panels produced.

Nanostructured polylactic acid/candeia essential oil mats obtained by electrospinning

This work aims to evaluate the effect of inclusion of different contents of candeia (Eremanthus erythropappus) essential oil (whose alpha-bisabolol is the main terpene) on the properties of polylactic acid (PLA) nanostructured mats and their relationship with fiber morphology and structure. The interaction occurring between the PLA and the candeia essential oil was confirmed by thermal and microscopy analysis. Addition of candeia essential oil increased nanofiber diameter and decreased the glass transition and melting temperatures of the nanofibers, suggesting lower energy input for processing. Scanning electron microscopy (SEM) images provided evidence of a homogeneous structure for the nanostructured mats. X-ray diffraction did not show differences in the crystallization of the nanofibers. This ongoing research confirms the possibility of incorporation of candeia essential oil in the production of nanofibers that will be studied for multipurpose applications.

Influência das características tecnológicas na cor da madeira de eucaliptos.

Due to importance of the color of the wood as a component of its description this study was undertaken to verify the influence of chemical components in the color of wood of various clones of eucalypt. The amount of lignin and polyphenols in the wood, the fibres dimensions and its specific gravity were determined. The colorimetric measurements were made through a specterphotometer Data Color 200d Microflash. It was verified by the characteristics of the wood studied, that the amount of extractives, basically polyphenols, had high correlation with the color of the wood.

Clones de Eucalyptus versus a produção de polpa celulósica.

The wood quality is defined by combining several intrinsic characteristics of the tree to its use. This research aimed to evaluate some of the wood characteristics of Eucalyptus clones and its performance in kraft pulping. Fifteen clones, 5.8 years-old were used, two trees from each clone, totaling thirty trees. The evaluated wood characteristics were: basic density, fiber dimensions (fiber length, wall thickness, lumen diameter) and chemical composition (cellulose, lignin, hemicelluloses, extractives and ash contents). Four samples were cooked at the laboratory for each tree, using different active alkali, to establish the delignification curve. These alkali loads were selected after exploratory cooking to obtain an eighteen kappa number at the medium point of the curve. In the cooking were appraised the screened, the pulp viscosity and consumed alkali. The yield results varied from 43.4 to 52.0%, the active alkali from 17.5 to 23.4%, the consumed alkali from 15.5 to 20.0% and the pulp viscosity from 19.9 to 61.4 cP.

Gaseificação de materiais lignocelulósicos para geração de energia elétrica.

The objective of this work was to build a countercurrent gasifier in hardened mortar to evaluate the potential of generating electrical energy of eucalyptus species grown in the state of Minas Gerais, from agroindustry residues and from the mixture of those materials. The immediate chemical composition and the heat power of the materials utilized were determined. The different lignocellulosic materials were experienced, and gas was used as the control. For the factors being tested, measurements of the electric yields and consumptions of the materials were performed. The statistical design was the completely randomized with seventeen treatments and three replicates done at 5% of significance. On the basis of the results obtained and on the statistical analyses performed, it follows that the gasifier-generator set is easy to build, made with easily purchased and low cost materials. Among the materials evaluated the coal of the species, Corimbia citriodora, with 78% of fixed carbon, presented the best performance of generated power, obtaining 1,391 watts, with a constant tension of 230 volts. The residues utilized of cane bagasse, rice straw, corn cob, coffee husk and coal chaff presented no potential to generate energy by the sort of gasifier utilized.

Umidade de equilíbrio de painéis de madeira

This study aimed at determining the equilibrium moisture content of wood panels in a climatization chamber and comparing the values of equilibrium moisture content found with those given by Nelsons equation. The research was developed at the Experimental Unit of Wood Panel Production of the Universidade Federal de Lavras. Samples of particleboard, plywood, hardboard, OSB (Oriented Strand Board), MDF (Medium Density Fiberboard), HDF (High Density Fiberboard), cement wood and plastic wood were taken both from commercial wood and from experiments and trials. The specimen dimensions were 2.60 cm width by 2.60 cm length, and thickness commercially used of each product. Five repetitions were carried out for each panel. The specimens were weighted and then taken to the climatization chamber under different conditions of relative humidity (90, 80, 70, 60, 50 and 40%) at 30oC. The hysteresis and equilibrium moisture content ranged from 40 to 90%. The results indicate that Nelsons equation is efficient for estimating the equilibrium moisture content and that there is no hysteresis difference in the studied products. All of them presented the same dimensional stability. It was also observed that panel coating did not affect the equilibrium moisture content.

Chemical characterization of the bark of Eucalyptus urophylla hybrids in view of their valorization in biorefineries

Abstract Eucalyptus urophylla hybrids are important raw materials for the forest industry in Brazil, and large quantities of barks are available at mill site that may be used for added-value products. The chemical composition of barks of six commercial hybrids clones of E. urophylla×E. grandis, E. urophylla×E. Camaldulensis, and undisclosed E. urophylla hybrids was studied. The hybrids had similar composition, on average (data based on oven dry bark): 16% extractives, mainly corresponding to polar compounds that are soluble in ethanol and water, 19% lignin, 47% polysaccharides, 1% suberin, and 2% ash. The polysaccharides consists mainly of cellulose as indicated by 84% of total neutral monosaccharides in the acid hydrolysate and 10% xylose. The compositions of the lipophilic extracts was determined by GC-MS before and after alkaline hydrolysis. In all the barks, fatty acids, and triterpenes (namely: betulinic and ursolic acids) were the most abundant compounds followed by smaller amounts of sterols, long-chain aliphatic alcohols, phenolic acids, and acylglycerols. The ethanol-water bark extract had a high phenolic content: total phenolics ranged 211–551 mg gallic acid equivalents (GAE) g-1 of extract, tannins 76–184 mg catechin equivalents (CE) g-1 extract, and flavonoids 98–234 mg CE g-1 of extract. The antioxidant activity corresponds to 338 mg Trolox g-1 of extract. Development of high-value products is proposed through an integrated biorefinery approach including valorisation of extractives and targeting for cellulose-based applications.

Qualidade de painéis aglomerados homogêneos produzidos com a madeira de clones de Eucalyptus urophylla

The study aimed to evaluate the potential of Eucalyptus urophylla clones to produce homogeneous particleboard of low-density. Six clones of Eucalyptus urophylla were evaluated, at 94 months of age and planted in Paracatu-MG. Pinus oocarpa wood was used as a reference. For each Eucalyptus urophylla clone and also for Pinus oocarpa, six panels were produced with urea-formaldehyde adhesive in the concentration of 6%, nominal density of 0.60 g/cm³, specific pressure of 40kgf/cm², temperature of 160oC and a time of 8 minutes. Eucalyptus urophylla clones presented potential for production of conventional particleboard of low density. Clones 62 and 28 showed the best results for all physical and mechanical properties evaluated, presenting properties equal or superior to those obtained for the panels produced with Pinus oocarpa wood. In relation to CS 236/1966 standard, only the clone 28 met all the requirements. None of the clones meets EN 312/2003 standard.

Efeito de algumas variáveis de processamento nas propriedades físicas de painéis de madeira de partículas alongadas.

The production of panels encompasses processing parameters that interfere in the properties and in the equilibrium moisture content of the panels such as specific gravities, compaction ratio, type and amount of adhesive, paraffin content, dimension and moisture content of the particles, time of closing the press, temperature and time of pressing and specific pressure. All these parameters can be controlled aiming to improve the quality of the panels. The study determined the influence of some processing variables (resin content, temperature and time of pressing) in the physical properties of the panels. At the Wood Technology and Forestry Products Laboratory of Universidade Federal do Parana, 27 homogeneous single layer measuring 480 x 480 x 15 mm were produced with strands without orientation and, at the Wood Technology and Forestry Products Laboratory of Universidade Federal Lavras, samples for the physical properties testing (thickness swelling, water absorption and the nonrecoverable tax – TNRE) were generated. Results demonstrated that the resin content, temperature and time of pressing affect drastically the retention of water by the panels.