Fine-tune of lignin properties by its fractionation with a sequential organic solvent extraction

[EN] In this work, different lignins were obtained from two different extraction methods (kraft and organosolv) but from the same raw material (Eucalyptus globulus sp.). They were subsequently fractionated to determine the differences of each extraction method and their corresponding physicochemical properties found in fractionation sequence and obtained fractions. The goal of the fractionation was to obtain lignin fractions with narrower molecular weight distribution and lower polydispersity index (PI). The solvent sequence was designed based on the environmental friendly properties, health and safety assessments of the selected organic solvents: (methanol (MeOH), ethanol (EtOH), propan-2-one (DMK), ethyl acetate (EtOAc), propan-1-ol (nPrOH), propan-2-ol (iPrOH), butan-2-one (MEK), and butan-1-ol (tBuOH)). The different fractions obtained were characterised to determine their chemical structure by several analytical techniques, such as Fourier Transformed Infrared Spectroscopy (FTIR), Ultraviolet (UV), Phosphorus-31 Nuclear Magnetic Resonance (P-31 NMR), Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS), Thermogravimetric analysis (TGA), and Differential scanning calorimetry (DSC). In addition, Gel Permeation Chromatography (GPC) was used to obtain the molecular weight distribution. This study showed an effective method for obtaining homogeneous lignins with specific structures and properties depending on the solvent and molecular weight attained. Moreover, the method designed was found to be effective regardless of the lignin extraction process employed; besides, various lignin fractions were obtained which were different from each other, having specific target applications depending on their structure and chemical properties, ranging from small molecules with abundant reactive sites to act as active materials or copolymer reagents for many applications, to larger and more inactive molecules with higher thermal resistivity.The authors would like to acknowledge the Basque Government for the financial support of this research through project IT1008-16 and grant PIF19-183. Furthermore, E. R. wants to acknowledge the tenure track position "BOIS" part of E2S UPPA supported by the "Investisse-ments d'Avenir" French program managed by ANR (ANR-16-IDEX-0002)

A forest-based circular bioeconomy for southern Europe: visions, opportunities and challenges

Addressing the societal and environmental challenges presented by global change requires fundamental changes to the way our society produces and consumes goods and services. Securing prosperity for a growing population, dealing with resource scarcity and mitigating climate change and environmental degradation will require an increased reliance on nature-based solutions, renewable energies and materials used in highly efficient and innovative closed material loops. That is what the circular bioeconomy can help to achieve

Geoeconomic variations in epidemiology, ventilation management, and outcomes in invasively ventilated intensive care unit patients without acute respiratory distress syndrome: a pooled analysis of four observational studies

Background: Geoeconomic variations in epidemiology, the practice of ventilation, and outcome in invasively ventilated intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) remain unexplored. In this analysis we aim to address these gaps using individual patient data of four large observational studies. Methods: In this pooled analysis we harmonised individual patient data from the ERICC, LUNG SAFE, PRoVENT, and PRoVENT-iMiC prospective observational studies, which were conducted from June, 2011, to December, 2018, in 534 ICUs in 54 countries. We used the 2016 World Bank classification to define two geoeconomic regions: middle-income countries (MICs) and high-income countries (HICs). ARDS was defined according to the Berlin criteria. Descriptive statistics were used to compare patients in MICs versus HICs. The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. Secondary outcomes were key ventilation parameters (tidal volume size, positive end-expiratory pressure, fraction of inspired oxygen, peak pressure, plateau pressure, driving pressure, and respiratory rate), patient characteristics, the risk for and actual development of acute respiratory distress syndrome after the first day of ventilation, duration of ventilation, ICU length of stay, and ICU mortality. Findings: Of the 7608 patients included in the original studies, this analysis included 3852 patients without ARDS, of whom 2345 were from MICs and 1507 were from HICs. Patients in MICs were younger, shorter and with a slightly lower body-mass index, more often had diabetes and active cancer, but less often chronic obstructive pulmonary disease and heart failure than patients from HICs. Sequential organ failure assessment scores were similar in MICs and HICs. Use of LTVV in MICs and HICs was comparable (42·4% vs 44·2%; absolute difference -1·69 [-9·58 to 6·11] p=0·67; data available in 3174 [82%] of 3852 patients). The median applied positive end expiratory pressure was lower in MICs than in HICs (5 [IQR 5-8] vs 6 [5-8] cm H2O; p=0·0011). ICU mortality was higher in MICs than in HICs (30·5% vs 19·9%; p=0·0004; adjusted effect 16·41% [95% CI 9·52-23·52]; p<0·0001) and was inversely associated with gross domestic product (adjusted odds ratio for a US$10 000 increase per capita 0·80 [95% CI 0·75-0·86]; p<0·0001). Interpretation: Despite similar disease severity and ventilation management, ICU mortality in patients without ARDS is higher in MICs than in HICs, with a strong association with country-level economic status