RESUMOCarvões ativados em forma de briquetes foram preparados a partir do resíduo da madeira de candeia, gerado no processo de extração do óleo α-bisabolol. O material foi briquetado, carbonizado e ativado com CO 2 , variando-se a temperatura (700-900°C) e o tempo de ativação (1-3 horas). Para a caracterização dos carvões ativados foram realizadas análise elementar (CHN-O), análise dos grupos funcionais (titulação de Boehm), buroff, área superficial BET estimada, índice de iodo, cálculo de área superficial com azul de metileno S AM , testes de adsorção com azul de metileno e fenol e índice de resistência mecânica. Os resultados mostraram que, com o aumento da temperatura e do tempo de ativação, ocorre aumento da área superficial, do volume de poros, da basicidade do carvão e da capacidade de adsorção de azul de metileno e de fenol.Palavras-chave:Candeia; Carvão Ativado; Briquete. ABSTRACTActivated carbons briquette shaped were prepared from Candeia wood waste, generated in the extraction of α-bisabololoil process. The material was briquetted, carbonized and activated with CO 2 , varying the temperature (700-900°C) and activation time (1-3 hours). The characterization of the activated carbons were performed by: elemental analysis (CHN-O), analysis of the functional groups (Boehm titration), Burn-off, estimated BET surface area, iodine index, calculation of surface area with methylene blue, adsorption tests with methylene blue (MB) and phenol and mechanical resistance (IRI).The results showed that increasing temperature and time of activation promoted an increased in the surface area, pore volume, basicity and adsorption capacity of AM and phenol.

A hybrid catalyst was prepared using cellulose nanofibrils and magnetite to degrade organic compounds. Cellulose nanofibrils were isolated by mechanical defibrillation producing a suspension used as a matrix for magnetite particles. The solution of nanofibrils and magnetite was dried and milled resulting in a catalyst with a 1:1 ratio of cellulose and magnetite that was chemically and physically characterized using light, scanning electron and transmission electron microscopies, specific surface area analysis, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, catalytic potential and degradation kinetics. Results showed good dispersion of the active phase, magnetite, in the mat of cellulosic nanofibrils. Leaching and re-use tests showed that catalytic activity was not lost over several cycles. The hybrid material produced was tested for degradation of methylene blue dye in Fenton-like reactions resulting in a potential catalyst for use in degradation of organic compounds.

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Large amount of waste of Candeia (Eremanthus erythropappus (DC.) Macleish) are ge e ated the e t a tio of esse tial oil ai l α-bisabolol) from wood. Since these waste has a limited use, without noble application by the industry, we decided to produce activated carbons (ACs) from these. The wood waste were carbonized at 550 °C, then were activated using CO 2 (g) under different temperatures and activation times. Activated carbons produced showed a BET area estimated between 303-1036 m 2 g -1 . The surface chemistry of the activated carbons were determined by Boehm titration, which indicated an increase of the number of the alkaline sites, if compared to carbonized material. Experimental data showed that the properties of the activated carbons depend on the variation of temperature and time activation. The adsorption tests of methylene blue and phenol were performed and adsorptions of 424 mg g -1 and 392 mg g -1 were respectively found.

Lignocellulosic materials have a complex polymeric structure, so, to obtain a high yield of glucose by hydrolysis reactions is necessary a pretreatment of the material. In this work, the effect of pretreatment corona (electric discharge) on different properties in three lignocellulosic materials (microcrystalline cellulose, cellulose pulp and bagasse) was evaluated. corona treatment was applied in three different exposure times (2, 6 and 10 minutes). Crystallinity, obtained by X-ray diffraction, showed a significant increase in samples of bagasse after pretreatment. No changes in acidity of materials was observed. Cationic and anionic tests indicate that the surface of bagasse is negatively charged after pretreatment. Amount of methylene blue adsorbed in the materials decreased with increasing of exposure time. Acid hydrolysis of materials with and without pretreatment were evaluated in amount of total reducing sugars (%TRS). A small decrease in %TRS occurred after pretreatment corona mainly in bagasse samples. HPLC analysis of hydrolysis products of pretreated bagasse showed higher yields in glucose, a raw material of interest for second generation ethanol.

Heteropolyacids are a class of compounds that can be used to catalyze a great range of reactions, either in homogeneous or heterogeneous phase, because they have good stability, solubility and high acidity. These compounds show good applicability in the use of biomass for biofuel production, as demonstrated in a variety of reports. This text presents a bibliographic research on the application of heteropolyacids in the production of biodiesel and bioethanol in the last years, as well as the reuse of byproducts of these processes.

In this work, two catalysts were produced to be used in hydrolysis of cellulose reactions to obtain glucose, a raw material used in the production of bioethanol. The heteropoly acid, H 3 PW 12 O 40 (HPW), reported as strong and thermally stable acid, was supported on activated carbon (AC) in a ratio varying from 1:1 to 2:1 to produce the catalysts AC-HPW (1:1) and AC-HPW (2:1). The catalysts were tested in cellulose hydrolysis evaluating some reaction variables and the results show the remarkable dependence of reaction temperature, amount and acidity of the catalyst. The results indicate the advantage of supporting HPW on carbonaceous material for using as catalyst in hydrolysis of cellulose, showing better conversion rate into sugars comparing with unsupported HPW.

Heteropoly salts containing different numbers of vanadium atoms (K 4 [PVW 11 O 40 (HPW), and used as catalysts in hydrolysis of cellulose reactions in order to change the redox properties and verify whether the cluster of catalysts are involved in mechanism reaction. The hydrolysis reactions following a full 23 factorial design with the variables: mass ratio (catalyst/substrate), reaction time and temperature. The variables evaluated were significant at a 90% confidence level including second and third order interactions. According to the conducted experiments, the catalysts were all active in hydrolysis. The best results occurred when HPW was used suggesting that the redox properties did not have much influence in depolymerization of cellulose and the hydrolysis mechanism are assigned to acidic properties of the medium. The main products obtained from the reactions were glucose and HMF, which are products of great interest in the chemical industry.