Search

Three lignocellulosic fractions with contrasted properties were produced by dry fractionation of olive pomace (OP): a stone-rich fraction (SF) rich in cellulose and having high polarity, a pulp-rich fraction (PF) richer in lignin and less polar, and a crude pomace fraction (CF) with intermediate properties. These fractions were used as fillers in two thermoplastic matrices, i.e . polyprolylene (PP) and polyhydroxybutyrate-co-valerate (PHBV). Tensile tests showed a decrease of both the stress and the elongation at break for all biocomposites, while the Young’s modulus was not significantly affected. At low filler contents, no effect of filler composition was observed whereas at high filler content (30 wt%), the decrease in the stress at break was less pronounced for PHBV-PF, with respective reduction values of 36%, 65% and up to 78% for PHBV-PF (30%), PHBV-CF (30%)and PHBV-SF (30%) composites, as compared to the neat PHBV. The elongation at break also greatly decreased according to the filler content. The highest reduction was recorded in the case of SF fillers, with a reduction of 74% for PHBV-SF composites. Mechanical properties were better preserved in the case of the PF filler due to better interfacial adhesion towards the matrices, as revealed by work of adhesion calculations, SEM observations and mechanical modelling. Water vapour permeability (WVP) of both matrices was increased in presence of both SF and CF fillers, while oxygen permeability was not significantly affected by the fillers. As an example, WVP increased from 0.9 ± 0.1 × 10 −12  mol m −1  s −1  Pa −1 for the neat PHBV up to 15.1 ± 2.6 × 10 −12  mol m −1  s −1  Pa −1 for PHBV-CF (30%). This supports a promising use of SF/CF fractions in sustainable biocomposites packaging for respiring food products, the PF-based formulations being more appropriate for non-respiring and water sensitive products. Our results demonstrated that the conditioning of lignocellulosic biomass by dry fractionation is important for the control of bio-based fillers properties and the resulting functionalities of biocomposites. Besides, the PP-based composites developed in this study allow reducing costs and dependence to fossil resources, while PHBV-based biocomposites also have the advantage of being fully bio-based and biodegradable. [ABSTRACT FROM AUTHOR]

Biorefinery was used to transform two organic wastes, i.e. urban park & garden green waste and porcine plasma (PPP), into raw materials for biocomposite production. The effect of the nature, size and content of the filler on the final performance of biocomposites was assessed. Two fractions stemming from an urban park and garden green waste, i.e. a representative fraction of the total waste (RF) and a branches-rich fraction (B), were considered as fillers of a PPP bioplastic. PPP-RF/B biocomposites were obtained by compression-moulding and then characterised by tensile tests, dynamic mechanical analysis, water uptake, and water vapour permeability. Using a filler size around 28 µm at 30 wt%, the Young's Modulus of samples including B fraction was double the value of that including RF, due to the presence of grass in the overall urban waste. Moreover, a greater strengthening was perceived when using larger particle sizes (around 140 µm) of the B fraction, highlighting the importance of the grinding stage. The loss tangent evolution with temperature from dynamic mechanical tests denoted an antiplasticizing effect of the urban biowastes, which should be considered in future applications as a certain exudation degree would be expected. Regarding barrier properties, water permeability increased at higher filler contents (i.e., 30 wt%), while oxygen permeability decreased. Generally, composites from plasma and urban biowaste could be considered in future applications (e.g., packaging), as they showed great reinforcement and stability during water immersion, apart from a darker tonality and decreased oxygen permeability. [Display omitted] • Lignocellulosic urban biowastes reinforce porcine plasma plastic materials. • An antiplasticization effect of lignocellulosic fillers happens on plasma plastics. • Water vapour permeability increases when fillers are included in plasma plastics. • Oxygen permeability decreases when fillers are included in plasma plastics. [ABSTRACT FROM AUTHOR]

In order to isolate polyphenols from Douglas fir outer bark, this latter was mechanically fractionated by means of knife and ball millings. The sieving of the resulting powder gave rise to a set of fractions with different particle sizes and shapes. The particles ranging from 0.56 to 0.16 mm size were mainly composed of tannins (46%) while, taxifolin was located in the coarser fraction (83%) with particles size above 1 mm. The isolated phenolic compounds are suitable of upgrading to higher value products. [ABSTRACT FROM AUTHOR]

Highlights: [•] Provide mathematical model for palm kernel oil fractionation feasibility assessment. [•] One stage fractionation yield 36.60% PKS IV7 or 24.15% PKS IV5. [•] Two stages fractionation yield 24.15% PKS IV5 and 10.51% PKS IV7. [•] Palm kernel stearin premium is correlated to palm kernel olein discount. [•] Double fractionation profitability is dependent on palm kernel olein discount. [ABSTRACT FROM AUTHOR]

The effect of dry fractionation on pulping and pulp properties of reed canary grass was studied for two alkaline pulping processes. Multivariate data analysis was used to evaluate the influence of dry fractionation, alkali charge and cooking time on pulp yield, screening reject, drainage, fibre length distribution, kappa number and residual alkali in black liquor for kraft and soda-anthraquinone pulping of the grass. Of the factors included in the design, dry fractionation had the greatest influence on all the responses. Dry fractionation gave a pulp with higher yield, lower screening reject, lower kappa number, better drainage and reduced fines for both pulping processes. [Copyright &y& Elsevier]