Tratamentos físico-químicos de bagaço de cana para produção de etanol por meio de hidrólise enzimática

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização térmica do bagaço de cana-de-açucar visando aproveitamento energético

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Preparação e caracterização de híbridos originados a partir do bagaço de cana-de-açúcar/NbOPO4.nH2O e sua aplicação em membranas como elemento filtrante

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização e estudo do comportamento térmico de ligninas extraídas de bagaço de cana-de-açúcar e resíduos sólidos urbanos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modificação da fração lignocelulósica durante o processo de compostagem do bagaço de cana-de-açúcar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Isolamento e seleção de fungos filamentosos termofílicos/termotolerantes produtores de celulases e xilanases e aplicação dos extratos enzimáticos na sacarificação do bagaço de cana-de-açúcar

Pós-graduação em Microbiologia - IBILCE

Avaliação térmica e estrutural do bagaço de cana de açúcar pré-tratado com ozônio, ultrassom e micro-ondas para produção de etanol celulósico por hidrólise enzimática

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Physical and mechanical characteristic of particleboards produced with residues of sugarcane and stem leaves of bamboo bonded with castor oil adhesive

In this research the aim was produce a particleboard with alternative materials and evaluated its physical and mechanical characteristics. The raw materials used are residues from sucarcane bagasse (SC) (Saccharum officinarum) and stem leaves of bamboo (B) (Dendrocalamus giganteus), bonded with a bi component adhesive based on castor oil. It was produced particleboards with five different traces: 100% SC, 75% SC+25% B, 50% SC+50% B, 25% SC +75%B and 100 % B. Their physical and mechanical characteristics were evaluated accordingly to Brazilian standard NBR 14810-3. Regarding the results obtained, it can be detached that for physical and mechanical evaluation it is evident a negative relation among the amount the sugarcane bagasse and their physical and mechanical characteristics, that is particleboards with low concentrations of sugarcane bagasse had better results. However all particleboards could be recommended for use as sealing particleboards in the segment of civil construction.

Pré-hidrólise ácida de bagaço de cana-de-açúcar e sua caracterização físico-química

The biomass resulting from processing sugarcane bagasse has been considered a source of cellulose with the potential production of bio-fuels. This lignocellulose can be processed into ethanol since is hydrolyzed by chemical processes (acids) or biotechnology (enzymes) which generate sugars suit for fermentation. This study had the objective to utilize physical and chemical pre-treatment processes for prehydrolysis of sugarcane bagasse. The experimental treatment was adjusted at a factor of 4 X 2, by the combination of pre-hydrolysis timing (15, 30, 45 and 60 minutes) and sulfuric acid concentrations (7.0% and 9.0%) which was incubated at a temperature of 121° C in an autoclave. The treatment data was subjected to analysis of the variance and averages which were compared using the Tukey test with a probability of 5%. The results obtained showed that through pretreatment acid applied on the lignocellulose material, there was a significant break from the substrate fibers like cellulose, hemicellulose and lignin.

Determinação do teor de glicose em bagaço de cana-de-açúcar hidrolizado pelo processo de conversão enzimática

The production of ethanol and sugar from sugarcane juice generate as byproduct, the bagasse. Currently, the bagasse, an industrial lignocellulosic biomass, can be used for production of second-generation ethanol, since when it is submitted to hydrolytic processes generates fermentable sugars. The objective of this study was to produce fungal enzymes capable of hydrolyzing this lignocellulosic biomass to generate glucose. For this, we used the mushroom species Lentinula edodes, Pleurotus ostreatus, Pleurotus eryngii, and Pycnoporus sanguineus as potential sources of laccase, manganese peroxidase and lignin peroxidase enzymes, capable of hydrolyzing the crushed sugarcane. The hydrolysis process was performed with the highest enzymatic activities observed from laccase in L. edodes (39.23 U-mL after 25 day incubation), P. ostreatus (2.5 U U-mL after 27 day incubation), P. sanguineus (80 U-mL after 27 days of incubation) and P. eryngii (16.45 U-mL 15 days incubation). MnP and LiP showed no significant results. The enzymatic hydrolysis of sugarcane bagasse in natura (32,17% hemicellulose, cellulose 52,45% and 10,62% lignin) and bagasse hydrolyzate with 7,0% H2SO4 (0,20% hemicellulose, 68,82% to 25,33% cellulose and lignin) were evaluated for each enzymatic obtained. Compared to others, the enzymes produced by P. sanguineus incubated in sugarcane bagasse showed better efficiency resulting in glucose with an average content of 0,14 g-L. Although the levels of glucose determined in this work were low in relation to the literature, it can be stated that the laccase, manganese peroxidase and lignin peroxidase enzymes demonstrated good hydrolytic potential, especially those produced by the fungus P. sanguineus.

Efeito dos compostos fenólicos e lignina sobre a ação de β-glicosidase

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

LIFE CYCLE ASSESSMENTS (LCAs) OF PYROLYSIS-BASED GASOLINE AND DIESEL FROM DIFFERENT REGIONAL FEEDSTOCKS: CORN STOVER, SWITCHGRASS, SUGAR CANE BAGASSE, WASTE WOOD, GUINEA GRASS, ALGAE, AND ALBIZIA

Renewable hydrocarbon biofuels are being investigated as possible alternatives to conventional liquid transportation fossil fuels like gasoline, kerosene (aviation fuel), and diesel. A diverse range of biomass feedstocks such as corn stover, sugarcane bagasse, switchgrass, waste wood, and algae, are being evaluated as candidates for pyrolysis and catalytic upgrading to produce drop-in hydrocarbon fuels. This research has developed preliminary life cycle assessments (LCA) for each feedstock-specific pathway and compared the greenhouse gas (GHG) emissions of the hydrocarbon biofuels to current fossil fuels. As a comprehensive study, this analysis attempts to account for all of the GHG emissions associated with each feedstock pathway through the entire life cycle. Emissions from all stages including feedstock production, land use change, pyrolysis, stabilizing the pyrolysis oil for transport and storage, and upgrading the stabilized pyrolysis oil to a hydrocarbon fuel are included. In addition to GHG emissions, the energy requirements and water use have been evaluated over the entire life cycle. The goal of this research is to help understand the relative advantages and disadvantages of the feedstocks and the resultant hydrocarbon biofuels based on three environmental indicators; GHG emissions, energy demand, and water utilization. Results indicate that liquid hydrocarbon biofuels produced through this pyrolysis-based pathway can achieve greenhouse gas emission savings of greater than 50% compared to petroleum fuels, thus potentially qualifying these biofuels under the US EPA RFS2 program. GHG emissions from biofuels ranged from 10.7-74.3 g/MJ from biofuels derived from sugarcane bagasse and wild algae at the extremes of this range, respectively. The cumulative energy demand (CED) shows that energy in every biofuel process is primarily from renewable biomass and the remaining energy demand is mostly from fossil fuels. The CED for biofuel range from 1.25-3.25 MJ/MJ from biofuels derived from sugarcane bagasse to wild algae respectively, while the other feedstock-derived biofuels are around 2 MJ/MJ. Water utilization is primarily from cooling water use during the pyrolysis stage if irrigation is not used during the feedstock production stage. Water use ranges from 1.7 - 17.2 gallons of water per kg of biofuel from sugarcane bagasse to open pond algae, respectively.

Thermochemical characterisation of agricultural wastes from West Africa

Thermochemical characterisation of agricultural biomass wastes from West African region has been carried out and their potential use as feedstock in thermochemical conversion processes determined. Proximate, ultimate, structural compositions, calorific values, thermogravimetry (TGA) and derivative thermogravimetry (DTG) analyses were carried out on corn straw and cobs, rice straw and husks, cocoa pod, jatropha curcas and moringa olifiera seed cakes, parinari polyandra fruit shell and sugarcane bagasse. Moringa olifiera seed cakes and cocoa pods were found to contain the highest moisture contents. Rice straw was found to contain a high ash content of 45.76. wt.%. The level of nitrogen and sulphur in all the samples were very low. Rice husk was found to have the highest lignin contents while corn cob low lignin contents indicate a potential feedstock source for quality bio-oil production using thermochemical process. © 2013.

Características físicas e mecânicas de misturas de solo, cimento e cinzas de bagaço de cana-de-açúcar

This work was done with the objective of studying some physical and mechanical characteristics of the sugarcane bagasse ash added to a soil-cement mixture, in order to obtain an alternative construction material. The sugarcane bagasse ash pre-treatment included both sieving and grinding, before mixing with soil and cement. Different proportions of cement-ash were tested by determining its standard consistence and its compressive resistance at 7 and 28 days age. The various treatments were subsequently applied to the specimens molded with different soil-cement-ash mixtures which in turns were submitted to compaction, unconfined compression and water absorption laboratory tests. The results showed that it is possible to replace up to 20% of Portland cement by sugarcane bagasse ash without any damage to the mixture's compressive strength.

Profiles of xylose reductase, xylitol dehydrogenase and xylitol production under different oxygen transfer volumetric coefficient values

BACKGROUND: Xylitol is a sugar alcohol (polyalcohol) with many interesting properties for pharmaceutical and food products. It is currently produced by a chemical process, which has some disadvantages such as high energy requirement. Therefore microbiological production of xylitol has been studied as an alternative, but its viability is dependent on optimisation of the fermentation variables. Among these, aeration is fundamental, because xylitol is produced only under adequate oxygen availability. In most experiments with xylitol-producing yeasts, low oxygen transfer volumetric coefficient (K(L)a) values are used to maintain microaerobic conditions. However, in the present study the use of relatively high K(L)a values resulted in high xylitol production. The effect of aeration was also evaluated via the profiles of xylose reductase (XR) and xylitol clehydrogenase (XD) activities during the experiments. RESULTS: The highest XR specific activity (1.45 +/- 0.21 U mg(protein)(-1)) was achieved during the experiment with the lowest K(L)a value (12 h(-1)), while the highest XD specific activity (0.19 +/- 0.03 U mg(protein)(-1)) was observed with a K(L)a value of 25 h(-1). Xylitol production was enhanced when K(L)a was increased from 12 to 50 h(-1), which resulted in the best condition observed, corresponding to a xylitol volumetric productivity of 1.50 +/- 0.08 g(xylitol) L(-1) h(-1) and an efficiency of 71 +/- 6.0%. CONCLUSION: The results showed that the enzyme activities during xylitol bioproduction depend greatly on the initial KLa value (oxygen availability). This finding supplies important information for further studies in molecular biology and genetic engineering aimed at improving xylitol bioproduction. (C) 2008 Society of Chemical Industry