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Background: The valorization of organic wastes through fast pyrolysis appears to be a highly promising option for decreasing pollutants and reducing consumption of natural resources. For this purpose, three different olive pomace samples were studied to determine how olive crop location and the extraction process could influence bio-oil product distribution. Olive pomace was selected as the feedstock due to the importance of the olive oil industry in Spain., Results: In this study, the conditions of fast pyrolysis were optimized using lignin as a reference, with the optimum conditions being 500 °C, 20 °C ms -1 as the heating rate and 15 s as the vapour residence time. The olive pomace results determined that not only their chemical composition, but also their fat content had a remarkable effect on product distribution obtained after fast pyrolysis. However, whereas high lignin content enhanced phenol production, cellulose decomposed to carboxylic acids. In addition, due to current global warming, the carbon dioxide (CO 2 ) burden of the three samples was calculated using mass spectroscopy. The OPGC sample gave off the lowest amount of greenhouse gases, followed by OPMNE and OPMN., Conclusions: The higher fat content in the sample enhanced carboxylic acid production. The difference in phenol production between OPMN and OPMNE could be attributed to the presence of potassium. From an environmental point of view, the use of olive pomace wastes could reduce CO 2 emissions with further research and by developing experimental processes. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)

The variable extent to which environmental factors are involved in soil carbon storage is currently a subject of controversy. In fact, justifying why some soils accumulate more organic matter than others is not trivial. Some abiotic factors such as organo-mineral associations have classically been invoked as the main drivers for soil C stabilization. However, in this research indirect evidences based on correlations between soil C storage and compositional descriptors of the soil organic matter are presented. It is assumed that the intrinsic structure of soil organic matter should have a bearing in the soil carbon storage. This is examined here by focusing on the methoxyphenols released by direct pyrolysis from a wide variety of topsoil samples from continental Mediterranean ecosystems from Spain with different properties and carbon content. Methoxyphenols are typical signature compounds presumptively informing on the occurrence and degree of alteration of lignin in soils. The methoxyphenol assemblages (12 major guaiacyl- and syringyl-type compounds) were analyzed by pyrolysis-gas chromatography-mass spectrometry. The Shannon-Wiener diversity index was chosen to describe the complexity of this phenolic signature. A series of exploratory statistical analyses (simple regression, partial least squares regression, multidimensional scaling) were applied to analyze the relationships existing between chemical and spectroscopic characteristics and the carbon content in the soils. These treatments coincided in pointing out that significant correlations exist between the progressive molecular diversity of the methoxyphenol assemblages and the concentration of organic carbon stored in the corresponding soils. This potential of the diversity in the phenolic signature as a surrogate index of the carbon storage in soils is tentatively interpreted as the accumulation of plant macromolecules altered into microbially reworked structures not readily recognized by soil enzymes. From a quantitative viewpoint, the partial least squares regression models exclusively based on total abundances of the 12 major methoxyphenols were especially successful in forecasting soil carbon storage., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Subcritical water was employed to fractionate woody biomass into carbohydrates and lignin. Nine urban trees species (hardwood and softwood) from Spain were studied. The experiments were carried out in a semi-continuous reactor at 250 °C for 64 min. The hemicellulose and cellulose recovery yields were between 30%wt. and 80%wt. while the lignin content in the solid product ranged between 32%wt. and 92%wt. It was observed that an increment of solubilized lignin disfavored the hydrolysis of hemicelluloses. It was determined that the maximum extraction of hemicellulose was achieved at 20 min of solid reaction time while the extraction of celluloses not exhibited a maximum value. The hydrolysis of hemicellulose and cellulose would be governed by the hydrolysis kinetic and the polymers accessibility. In addition, the extraction of hemicellulose was negatively affected by the lignin content in the raw material while cellulose hydrolysis was not affected by this parameter., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The aim of this work was to chemically characterize orange tree prunings and use it in pulping and combustion processes. Soda-anthraquinone pulping of the main fraction of orange pruning (stems with a diameter > 0.5 cm) was simulated with polynomial and neurofuzzy models, that predicted pulp properties as a function of operating variables (155-185°C, 40-90 min, soda concentration, 10-16%) with errors less than 20%. The heating values (16,870 kJ/kg), the flame temperature (1150-2150 °C) and dew point temperature of fuel gas (47-53 °C) for the residual fraction from orange pruning (stems diameter < 0.5 cm and leaves) was determined and compared with other non-wood lignocellulosic materials. As a consequence the price of kJ obtained by combustion of this residual fraction is less than other lignocellulosic materials, much lower than those of fossil fuels., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

We studied the structure of alcohol-soluble lignin in cognac spirits from Spain (7-year aging) and Azerbaijan (15-year aging). Alcohol-soluble lignin was precipitated and refractionated by means of preparative high-performance liquid chromatography. Lignin was studied by the method of high-performance liquid chromatography and mass spectrometry. Lignin hydrolysis products were assayed by the method of gas-liquid chromatography and mass spectrometry. The structure of lignans was reconstructed from these fragments. Lignans from Spanish and Azeri alcohol were arbitrarily designated as sinapoconiferal triglycoside and glucoferulate flavone diglycoside, respectively.