ResumoObjetivou-se realizar a caracterização energética de espécies de eucalipto para a produção de carvão vegetal. As espécies utilizadas foram Eucalyptus grandis x Eucalyptus urophylla, Eucalyptus propinqua, Eucalyptus robusta, Eucalyptus pellita e Eucalyptus botryoides. Avaliou-se o poder calorífico, densidades básica e energética, o rendimento gravimétrico e a análise química imediata do carvão vegetal. O experimento foi conduzido em delineamento inteiramente casualizado, com 3 repetições. A unidade experimental foi a tora, em que coletou-se discos com 5 cm de espessura, localizados à 0, 25, 50, 75 e 100% da altura total da árvore. As carbonizações foram realizadas em forno elétrico com temperatura final de 380 ºC. Realizou-se a ANOVA, teste Tukey e correlação segundo Pearson, todos a 5,0% de probabilidade. O poder calorífico da madeira e o rendimento não se diferiram significativamente entre as espécies em estudo. Os rendimentos médios encontrados foram de 39,65% em carvão e 21,06% em gases não condensáveis. O Eucalyptus robusta apresentou características energéticas semelhantes ao híbrido de Eucalyptus grandis x Eucalyptus urophylla, exceto pelas densidades, que naquele foram superiores. A densidade energética da madeira aumentou proporcionalmente à densidade básica, sendo que, a madeira mais densa apresentou maior quantidade de energia disponível. Conclui-se que, as características potenciais (PCS, Db e De) na produção de carvão vegetal foram evidenciadas em todas as espécies, no entanto, o Eucalyptus robusta foi a espécie mais promissora para fins energéticos para ser utilizada como biorredutor. Palavras-chave: Biomassa; carvão vegetal; Fonte renovável. AbstractEnergy characterization of different species of Eucalyptus. This study aimed to carry out energy characterization of Eucalyptus species for charcoal production. The species used were Eucalyptus grandis x Eucalyptus urophylla, Eucalyptus propinqua, Eucalyptus robusta, Eucalyptus pellita and Eucalyptus botryoides. The calorific value, basic and energetic densities, gravimetric yield and the immediate chemical analysis of charcoal were evaluated. The experiment was conducted in a completely randomized design with three replications. The experimental unit was the log, where 5 cm thick discs were collected at 0, 25, 50, 75 and 100% of the total height of the tree. The carbonization were carried out in an electric furnace with a final temperature of 380°C. Were evaluated the calorific power, basic and energy densities, yields of carbonization and chemical analysis. Were realized ANOVA, Tukey test and Pearson correlation, all at 5.0% probability. Calorific power of the wood and the carbonization yields did not differ significantly between the species under study. The average yields were 39.65% in coal and 21.06% in non-condensable gases. Eucalyptus robusta showed characteristics similar to the hybrid of Eucalyptus grandis x Eucalyptus urophylla, except for densities that were higher in first. The energy density of wood increases with increasing density, ...

RESUMOA fim de melhorar a eficácia global da produção de energia, uma estratégia é o modelo de biorrefinarias, em que todos os componentes de biomassa são totalmente utilizados para produzir uma gama de produtos de maior valor agregado. A lignina kraft é um dos produtos oriundos do processo de produção de celulose e que pode ser utilizado na confecção de materiais densificados. O objetivo deste trabalho foi avaliar o comportamento da adição da lignina extraída do licor negro kraft em briquetes confeccionados com resíduos da indústria moveleira na forma de maravalha e partículas de painéis; em diferentes proporções. Os briquetes foram produzidos em briquetadeira laboratorial, usando as temperaturas de 60, 75 e 90 o C. O tempo de compactação e resfriamento foi de 5 minutos e pressão 68,9 x 10 5 N.m -2 (1000 PSI). A qualidade dos briquetes foi avaliada em função da determinação da propriedade mecânica. Determinou-se a carga de ruptura dos briquetes. A adição de lignina kraft aos resíduos de madeira nas proporções e temperatura adequadas apresentou vantagens de aumento de resistência mecânica dos briquetes. A lignina kraft apresentou vantagens como aglutinante na produção de briquetes de resíduo de madeira na temperatura de compactação de 90 °C com adição de 20% de lignina kraft e temperaturas de 60 e 75 °C de compactação na proporção de adição de 40 e 60% de lignina kraft, respectivamente. Palavra-chave: briquetes; aglutinante; resíduo indústria moveleira.

Among the technological alternatives to improve the quality and use of eucalyptus wood is heat treatment, as the wood has some features that may limit its use, such as dimensional instability, high anisotropy, and heterogeneous coloring. This study is aimed at evaluating the effect of time of hydrothermal treatment on physical, chemical, and mechanical properties of solid wood of Eucalyptus grandis. We used three trees of E. grandis, selecting only the heartwood, and prepared test specimens with dimensions of 30cmx8cmx3cm (length, width, and thickness). The hydrothermal treatment was performed in a Parr reactor using three reaction times (5, 15, and 25min) at 140°C. Partial removal of extractives occurred, especially in the outer layer of wood. There was an increase of up to 58% of its permeability because of the partial clearing of the vessel elements. There was no degradation of the main constituents of the wood, so loss of mechanical strength was observed. The hydrothermal treatment promoted the partial removal of the hydroxyl groups and/or a structural rearrangement of the hemicelluloses and cellulose, causing a reduction of the hygroscopicity of E. grandis.

Research indicates the use of adsorbent materials to remove pollutants from wastewater and effluents, which can be obtained from renewable materials such as biomass, biopolymers (chitosan) or composites. Thus, the objective of this work was to produce and evaluate activated carbon (AC) and chitosan composite films as adsorbents of neutral red dye. AC films were produced using CO 2 and water vapor. The variables of the activation process were time (1 and 2 h) and temperature (600 and 750 C). Five films were produced, with one pure chitosan (T1) film and four activated carbon with chitosan films (T2, T3, T4 and T5). The T2 film refers to activated carbon produced at 600 C for 1 h þ chitosan, T3 to activated carbon produced at 600 C for 2 h þ chitosan, T4 to activated carbon produced at 750 C for 1 h þ chitosan and T5 to activated carbon produced at 750 C for 2 h þ chitosan. The T5 film increased its adsorption capacity by approximately 87% and its removal efficiency of neutral red dye by 43% compared to T1. The presence of activated carbon in the films provided an increase in the adsorption capacity of the neutral red dye.

Due to the physiological differences in the juvenile and adult phases of teak wood, differentiation occurs in the impregnation by extractive materials along the heartwood regions, assuming that there is also a significant variation in the permeability of this material. Thus, the study aimed to evaluate the influence of age on the heartwood / sapwood ratio (H/S), permeability, and extractives content of Tectona grandis L.f wood. Four ages (10, 12, 14, and 16 years) and four trees (repetitions) were evaluated, totaling 16 samples. The H/S ratio, extractive content, and wood permeability were determined, in addition to the average and maximum permeability among all ages selected for calculation of their porosity. The H/S ratio increased over the ages of 10 and 16, and the content of extractive materials increased until the age of 14. There was a high heterogeneity between the permeability values of the wood at all ages analyzed, and one of the possible explanations for this fact is the presence of tyloses in different places on the trunk and the arrangement of the pores around the growth rings.