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Biomass thermochemical liquefaction is a chemical process with multifunctional bio-oil as its main product. Under this process, the complex structure of lignocellulosic components can be hydrolysed into smaller molecules at atmospheric pressure. This work demonstrates that the liquefaction of burned pinewood from forest fires delivers similar conversion rates into bio-oil as non-burned wood does. The bio-oils from four burned biomass fractions (heartwood, sapwood, branches, and bark) showed lower moisture content and higher HHV (ranging between 32.96 and 35.85 MJ/kg) than the initial biomasses. The increased HHV resulted from the loss of oxygen, whereas the carbon and hydrogen mass fractions increased. The highest conversion of bark and heartwood was achieved after 60 min of liquefaction. Sapwood, pinewood, and branches reached a slightly higher conversion, with yields about 8% greater, but with longer liquefaction time resulting in higher energy consumption. Additionally, the van Krevelen diagram indicated that the produced bio-oils were closer and chemically more compatible (in terms of hydrogen and oxygen content) to the hydrocarbon fuels than the initial biomass counterparts. In addition, bio-oil from burned pinewood was shown to be a viable alternative biofuel for heavy industrial applications. Overall, biomass from forest fires can be used for the liquefaction process without compromising its efficiency and performance. By doing so, it recovers part of the lost value caused by wildfires, mitigating their negative effects.

The circular economy plays an important role in the preparation and recycling of polymers. Research groups in different fields, such as materials science, pharmaceutical and engineering, have focused on building sustainable polymers to minimize the release of toxic products. Recent studies focused on the circular economy have suggested developing new polymeric materials based on renewable and sustainable sources, such as using biomass waste to obtain raw materials to prepare new functional bio-additives. This review presents some of the main characteristics of common polymer additives, such as antioxidants, antistatic agents and plasticizers, and recent research in developing bio-alternatives. Examples of these alternatives include the use of polysaccharides from agro-industrial waste streams that can be used as antioxidants, and chitosan which can be used as an antistatic agent.

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GONÇALVES, DIOGO ARISTÓTELES RODRIGUES. Fosfatos naturais reativos e calcinados na fosfatagem da cana-de-açúcar. 2021. 70f. Tese (Doutorado em Agronomia) -Universidade Federal de Uberlândia, Uberlândia. 1 Os solos tropicais apresentam elevada acidez, baixa saturação por bases, e baixa disponibilidade de nutrientes, como o fósforo (P). O P fornecido na adubação torna-se gradualmente indisponível, devido, à adsorção ao solo, o que gera recomendações de altas doses de P, elevando os custos de produção. Assim, fontes alternativas de P são pesquisadas, pois têm se mostrado capazes de competir com as fontes convencionais em eficiência e custo. O presente estudo teve como objetivo avaliar a eficiência agronômica de fontes de P aplicadas em área total antes do plantio da cana-de-açúcar. Foram utilizadas 6 fontes de fósforo na dose de 100 kg ha -1 de P2O5 sendo: FNR OCP Heringer, FNR OCP Heringer mais ácido húmico, termofosfato calcinado granulado e farelado, Fosfato Itafós e FNR Bayovar. Doses adicionais foram estabelecidas para: termofosfato calcinado granulado (50, 150, 200 kg ha -1 de P2O5) e farelado (150 kg ha -1 de P2O5); FNR OCP Heringer (50, 150 e 200 kg ha -1 de P2O5); outro tratamento sem fosfatagem foi adicionado. Foi avaliada a disponibiliade de Ca, Mg, P e Si para o solo e nas plantas, o efeito na produtividade e qualidade da cana-de-açúcar e o acumulado de produção. O termofosfato calcinado granulado aplicado a lanço apresentou resultados superiores em relação às demais fontes fosfatadas para a biometria da cana-de-açúcar. A produção de colmos e açúcar não foi afetada pelas doses de termofosfato calcinado ou fosfato natural reativo OCP nos dois locais, para nenhum dos cortes avaliados. A aplicação de termofosfato gera resultados positivos para o solo e a cana-de-açúcar; porém, nem todas as condições de aplicação do termofosfato vão gerar resultados significativamente superiores às demais fontes ou ao tratamento controle.

Liquefaction of biomass delivers a liquid bio-oil with relevant chemical and energetic applications. In this study we coupled it with short rotation coppice (SRC) intensively managed poplar cultivations aimed at biomass production while safeguarding environmental principles of soil quality and biodiversity. We carried out acid-catalyzed liquefaction, at 160 °C and atmospheric pressure, with eight poplar clones from SRC cultivations. The bio-oil yields were high, ranging between 70.7 and 81.5%. Average gains of bio-oil, by comparison of raw biomasses, in elementary carbon and hydrogen and high heating, were 25.6, 67, and 74%, respectively. Loss of oxygen and O/C ratios averaged 38 and 51%, respectively. Amounts of elementary carbon, oxygen, and hydrogen in bio-oil were 65, 26, and 8.7%, and HHV averaged 30.5 MJkg−1. Correlation analysis showed the interrelation between elementary carbon with HHV in bio-oil or with oxygen loss. Overall, from 55 correlations, 21 significant and high correlations among a set of 11 variables were found. Among the most relevant ones, the percentage of elementary carbon presented five significant correlations with the percentage of O (−0.980), percentage of C gain (0.902), percentage of O loss (0.973), HHV gain (0.917), and O/C loss (0.943). The amount of carbon is directly correlated with the amount of oxygen, conversely, the decrease in oxygen content increases the elementary carbon and hydrogen concentration, which leads to an improvement in HHV. HHV gain showed a strong positive dependence on the percentage of C (0.917) and percentage of C gain (0.943), while the elementary oxygen (−0.885) and its percentage of O loss (0.978) adversely affect the HHV gain. Consequently, the O/C loss (0.970) increases the HHV positively. van Krevelen’s analysis indicated that bio-oils are chemically compatible with liquid fossil fuels. FTIR-ATR evidenced the presence of derivatives of depolymerization of lignin and cellulose in raw biomasses in bio-oil. TGA/DTG confirmed the bio-oil burning aptitude by the high average 53% mass loss of volatiles associated with lowered peaking decomposition temperatures by 100 °C than raw biomasses. Overall, this research shows the potential of bio-oil from liquefaction of SRC biomasses for the contribution of renewable energy and chemical deliverables, and thereby, to a greener global economy.

Influência de diferentes fontes de fósforo e tamanho do tolete no desenvolvimento da cana-de-açúcar (Saccharum officinarum) Influence of different sources of phosphorus and stem size on the development of sugarcane (Saccharum officinarum

Eucalyptus globulus sawdust is a residue from the pulp and paper industry which has been underutilised and undervalued. The thermochemical liquefaction of sawdust can be considered an alternative for recycling this residue, as it results in the production of a bio-oil that, when extracted in water, allows the obtention of an aqueous solution composed of carbohydrates. The sugars resulting from the aqueous fraction of bio-oil can be valued by and applied in the industry to produce sustainable materials. For the first time, the sugar composition of the aqueous extract of bio-oil was disclosed, identified, and quantified by a high-pressure liquid chromatograph (HPLC) coupled to a refractive index (RID) detector containing fructose (36.58%) and glucose (33.33%) as the main components, sucrose (15.14%), trehalose (4.82%) and xylose (10.13%). The presence of these sugars was further confirmed by two-dimensional (2D) 1H-13C heteronuclear single-quantum correlation–nuclear magnetic resonance (HSQC–NMR) spectroscopy. Fourier-transform infrared (FTIR-ATR) and elemental analyses were also used. In addition, the pathway leading to the identified sugars is also suggested.