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Biorefinery is a new term to designate two main subjects, bioproducts and bioenergy, which play important roles towards a more bio-based society. This paper reviews the current biorefineries model as well as its future importance focusing on pulp mill opportunities. There are currently several different levels of integration in biorefineries which add to their sustainability, both economically and environmentally. Enzymatic pretreatment for biomass deconstruction aiming to release the polysaccharides is a key technology in the future biorefineries and it is currently the subject of intensive research.

The efficient use of renewable resources has become a driving force for the worldwide industry aiming to improve the competitiveness. Considering the available natural raw materials, the lignin present in the lignocellulosic biomass such as trees, is the unique natural polymer that presents aromatic rings in its constitution. In this way, this review details the structure of native lignin as well as the technical lignin, including information on the characteristics that this polymer must have for the most promissory applications as feedstock for bioproducts. Approximately 50 million tons of lignin are produced worldwide annually, of which 98% to 99% is incinerated to produce energy and steam in the pulp mills. Only a small fraction of the lignin, derived mainly from the sulfite pulp mill is recovered commercially in a biorefinery concept. There are many opportunities for producing high value-added products from technical lignin, mainly considering the pulp mills growing, and environmental restrictions using non-renewable raw materials. The currently trend have shown that technical lignin sources may also be used as feedstock for phenol derived products, technical carbons, fuels, and adhesives. On the other hand, there are some technological hurdles must be overcome to make these uses feasible.

Brazil has 8.51 million km 2 of territorial area and a tropical climate. In 2010, the occupation of the Brazilian soil consists of 20.8% pasture, 6.8% agriculture, 0.8% forested areas, 61.0% natural forests, and 9.7% other areas. In 2012, of the total area of the country 3.25% (27.65 million ha) is occupied by soy bean cultivation and 1% (8.5 million ha) by sugar cane cultivation. In 2012, the main cultivated species in the country were Eucalyptus spp. (71.0%), Pinus spp. (21.75%), Acacia mearnsii and Acacia mangium (2.12%), Hevea brasiliensis (2.36%), and Schizolobium amazonicum (1.22%). From 2004 to 2012, the planted forest area growth was 50.4%. The main factor that boosted this growth was the demand of the pulp and paper, followed by wood-based panels sector. It is also notable the development of new planted forests in Brazil for energy purposes. In recent decades, scientific and technological advance shave resulted in significant improvements in productivity, resistance to diseases, uniform degree of the forest plantations, wood quality etc. Among the most researched species are the ones belonging to Eucalyptus gender for having excellent adaptability to the edaphoclimatic conditions in the country. The current average productivity of Eucalyptus is of 40.7 m 3 /ha·year. In some regions of the country the average productivity of Eucalyptus has reached 100 m 3 /ha·year. The Brazilian forestry industry uses mainly planted forests, and the pulp and paper industry consumes only this type of wood. The pulp and wood panel sectors are more technologically advanced in relation to the other wood products sectors.

Wood autohydrolysis for xylan removal prior to kraft pulping and the consequences of this practice downstream in a kraft pulp mill has been investigated. Chip autohydrolysis for 60 min at 165 °C removed 61% of the xylans, but subsequent kraft cooking produced a 9.4% lower yield than reference. Pulp from 60-min autohydrolyzed chips showed 75% efficiency in oxygen delignification compared to 43.6% from the reference, resulting in a subsequent ECF bleaching cost reduction of 36% and significant effluent improvement. The chip autohydrolysis process resulted in a pulp of higher bulk, lower beatability and strength in relation to the reference, and an acid hydrolysate of low xylan concentration. Pulp cellulose and xylan derived from autohydrolyzed chips are less stable during kraft pulping because of their low molecular weight and high polydispersity. Xylan−lignin and cellulose−lignin complexes from kraft pulps derived from autohydrolyzed chips contain lignin of higher molecular weight than that of regular kraft pulp.

the evaluation of eighteen eucalypt clones obtained from the Brazilian Genolyptus project, regarding their potential characteristics for pulp production. Aiming at the same goal, two species of elephant grass were also evaluated as alternative raw material sources. Through the analyses of the anatomic and chemical characteristics, five eucalypt clones and one elephant grass species were indicated for pulp production and biorefinery application. The results of this study indicate the high technological quality of Eucalyptus clones evaluated and indicate that they can be used for biorefinery applications since they have the suitable characteristics. In general, the eucalypt clones are less moist and denser and contain fewer minerals and extraneous materials than the elephant grass species, which make them more attractive for utilization in deconstruction studies aiming at production of bioproducts.

Researching for new biomaterials intended for drug delivery systems has considerably intensified in recent years. There is an increasing interest in PBS (poly[butylene succinate]) and its copolymers as biomaterials due to the possibility of synthesis of the PBS from a renewable source. Among these copolymers, PBS‐PEG (poly[butylene succinate‐co‐polyethylene glycol]) is studied for materials that have shape memory and are biodegradable. However, to date, no research into the use of PBS‐PEG to prepare microspheres for drugs release has been reported. Herein, PBS‐PEGs with three PEG with different chain′s length were synthesized by polycondensation reaction and characterized by means of SEC, FTIR, DSC, TGA, and DRX. Naproxen loaded microspheres were prepared by an oil‐in‐water (o/w) single emulsion technique. The drug release was followed by UV‐Vis. The presence of PEG had a marked effect on the in vitro release profiles. The mathematical models employed show that the fundamental mechanism of release is diffusion when PEG is present in the polymer matrix of the particle.