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Pre-treatment of lignocellulosic biomass using ionic liquids: wheat straw fract...

This work is devoted to study pre-treatment methodologies of wheat straw with 1-ethyl-3-methylimidazolium acetate ([emim][CH3COO]) and subsequent fractionation to cellulose, hemicellulose and lignin. The method developed and described here allows the separation into high purity carbohydrate and lignin fractions and permits an efficient IL recovery. A versatility of the established method was confirmed by the IL...

Produção de xilitol: uma via alternativa de valorização do bagaço de azeitona e...

Métodos de fraccionamento de biomassa para as biorrefinarias

O desenvolvimento de processos que permitam o fraccionamento eficiente da biomassa (tradicionalmente designados por pré-tratamentos) constitui uma parte muito significativa do esforço científico que tem sido feito para a transformação das biorrefinarias numa realidade industrial. Este artigo apresenta uma breve revisão dos processos de fraccionamento, sendo dada particular atenção a processos emergentes, discu...

Industry-based biorefineries

Deconstruction of the hemicellulose fraction from lignocellulosic materials int...

Hemicelluloses hold a great promise for the production of added-value compounds in the biorefinery framework. Specifically, the xylan-rich hemicelluloses from hardwoods and agro-industrial residues present themselves as effective feedstock choices for the biotechnological production of xylitol. This paper reviews the various hemicellulose structures present in such materials and critically evaluates the availab...

Separation of oligosaccharides from caprine milk whey, prior to prebiotic evalu...

Milk oligosaccharides are believed to have beneficial biological properties. Caprine milk has a relatively high concentration of oligosaccharides in comparison with other ruminant milks and has the oligosaccharide profile closest to that of human milk. The first stage in recovering oligosaccharides from caprine milk whey, a by-product of cheese making, was accomplished by ultrafiltration to remove proteins and ...

Comparison of GA and PSO performance in parameter estimation of microbial growt...

In this work we examined the performance of two evolutionary algorithms, a genetic algorithm (GA) and particle swarm optimization (PSO), in the estimation of the parameters of a model for the growth kinetics of the yeast Debaryomyces hansenii. Fitting the model’s predictions simultaneously to three replicates of the same experiment, we used the variability among replicates as a criterion to evaluate the optimiz...

Hydrothermal processing of hardwoods and agro-industrial residues :evaluation o...

Autohydrolysis was used as a pre-treatment method for the selective hydrolysis of hemicelluloses of four lignocellulosic materials: eucalypt wood chips (EWC), corn cobs (CC), wheat straw (WS) and brewery’s spent grain (BSG), and the process was optimized towards the production of xylo-oligosaccharides (XOS). The effects of temperature, both at isothermal (150-190ºC), and non-isothermal (up to 240ºC) conditions,...

The pros and cons of the dedicated upgrade of the hemicellulosic sugar stream i...

The challenge of the future integrated biorefineries is the full economically utilization of all biomass components with the simultaneously production of fuels and chemicals, preferably of added-value. This can only be achieved by the selective fractionation of the lignocellulosic biomass into its polymeric components, thus increasing their individual upgradeability to enhance the process economics. To reach th...

Simplex optimization and mathematical modeling of wheat straw dilute acid hydro...

Wheat straw is an interesting biorefinery raw material, due to its abundance, chemical composition, and cost. Among the different pretreatments suitable for its processing, dilute acid hydrolysis still presents some benefits due to its simplicity. Nevertheless, it requires a careful optimization to avoid excessive by-products formation and catalyst spending. An attractive and simple optimization approach is the...