Browsing by Author "Santos, Jorge"

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Forest by-Product Valorization: Pilot-Scale Pinus radiata and Eucalyptus globulus Bark Mixture Extraction
    (2023) Santos, Jorge; Escobar-Avello, Danilo; Fuentealba, Cecilia; Cabrera-Barjas, Gustavo; Gonzalez-Alvarez, Julia; Martins, Jorge M.; Carvalho, Luisa H.
    One of the most important by-products generated in the forestry industry is the bark obtained during the debarking process. Pine (Pinus radiata D. Don) and eucalyptus (Eucalyptus globulus L.) are the main important tree species exploited in the Chilean forestry industry. The bark of P. radiata D. Don is an interesting source of extracts, rich in condensed tannins, with potential uses in biopolymer and bioadhesive preparation. Conversely, the E. globulus bark extracts are rich in hydrolyzable tannins with few applications. Nevertheless, the forest industry generates a high volume of these by-products, simultaneously. Then, it is interesting to determine a suitable process for the joint valorization of both forest by-products at a large scale. In this work, alkaline extraction (NaOH and Na2SO3) was performed at a pilot scale of a mixture of E. globulus and P. radiata barks prepared at different ratios (0%-100%). The effect of bark mixture composition on the resulting extract's properties was evaluated. All extracts were characterized according to their chemical composition by FTIR-ATR, MALDI-TOF, and molecular weight distribution (GPC). In addition, the Stiasny number was tested to determine the potential use of extracts in bioadhesive formulation. The self-condensation reaction of resulting extracts was studied using Dynamic Mechanical Analysis (DMA) and Automated Bond Evaluation System (ABES) techniques. Results show a good interaction between condensed and hydrolyzable tannins from both species' barks. It also demonstrated the potential application of the obtained extracts, for a bark ratio of 50:50, in the formulation of bioadhesives for particleboard manufacture. The obtained product showed a similar performance to that of the bioadhesive formulated with the extract obtained using only P. radiata bark.
  • No Thumbnail Available
    Item
    Grape Canes (Vitis vinifera L.) Applications on Packaging and Particleboard Industry: New Bioadhesive Based on Grape Extracts and Citric Acid
    (2022) Santos, Jorge; Pereira, Joao; Escobar-Avello, Danilo; Ferreira, Irene; Vieira, Carlos; Magalhaes, Fernao D.; Martins, Jorge Manuel; Carvalho, Luisa H.
    The main by-product generated in the wine industry are the grape canes, derived from the pruning process. In order to increase the valorisation possibilities of this highly polyphenolic lignocellulosic material, this work focuses on its applicability in the materials industry. As a first step, we demonstrate the viability of using grape cane particles as raw material for particleboard production, combined with a melamine formaldehyde urea (MFU) binder. In addition, looking for the application of these particleboards in the food packaging industry, particleboards based on grape canes were also produced using a new bioadhesive, obtained from the grape cane extract and citric acid. The self-condensation reaction of the grape cane extracts, and the curing reaction with citric acid, were studied by FTIR-ATR and ABES showing the feasibility of this new bioadhesive formulation. Looking for a zero-waste process, the effect of the type of raw material (fresh grape cane, solid by-product of the extraction) and of the extract used on the properties of particleboard were also studied. Citric acid was demonstrated to be a good crosslinking agent for grape cane extract. This work shows that it is possible to produce a new lignocellulosic product based only on grape cane particles using a binder based on grape cane extracts and citric acid. The implemented methodology allowed producing particleboards with applicability in the food-packaging industry, minimizing the waste generated in the process.
  • No Thumbnail Available
    Item
    High-value compounds obtained from grape canes (Vitis vinifera L.) by steam pressure alkali extraction
    (2022) Santos, Jorge; Escobar-Avello, Danilo; Magalhaes, Pedro; Martins, Jorge Manuel; Gonzalez-alvarez, Julia; Carvalho, Luisa Hora de
    The main by-product generated by the wine industry is the grape canes derived from the pruning process. The aim of the current work was the valorisation of this highly poly phenolic lignocellulosic material, by alkali extraction methodology avoiding alcoholic solvents use. In lignocellulosic by-products valorisation, it is important to take into account the variability of the raw material. In the case of vine pruning this may be due to the different varieties used, the geographical area, the climate, or the processing. It is, however, important to develop a global strategy for valorisation, from a biorefinery and circular economy point of view. In this work, the grape canes were characterised, before and after the extraction process, by Fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR) spectroscopy. Changes in cellulose crystallinity, hemicellulose content and structural conformation of proteins, due to the alkali thermal extraction process were identified and evaluated. For the first time, a steam pressure alkali extraction method was used on this material. The products were characterised by FTIR-ATR and Matrix Assisted Laser Desorption Ionisation-Time of Flight (MALDI-TOF) mass spectrometry. The presence of high-value compounds such as stilbene oligomers and condensed tannins was demonstrated in the extracts. The work shows the viability of the steam pressure alkali extraction, a simple and environmentally friendly method, for grape cane valorisation. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.
  • No Thumbnail Available
    Item
    Pretreated Eucalyptus globulus and Pinus radiata Barks: Potential Substrates to Improve Seed Germination for a Sustainable Horticulture
    (2023) Escobar-Avello, Danilo; Ferrer, Victor; Bravo-Arrepol, Gaston; Reyes-Contreras, Pablo; Elissetche, Juan P.; Santos, Jorge; Fuentealba, Cecilia; Cabrera-Barjas, Gustavo
    Commercial forest plantations in Chile are dominated by pine (Pinus radiata) and eucalyptus (Eucalyptus globulus). Tree bark is the main by-product of the forestry industry and has low value, but great potential for use as an agricultural substrate. However, the direct use of bark fibers may cause plant phytotoxicity due to the presence of polyphenolic and other compounds. This study aims to evaluate the physicochemical properties of E. globulus and P. radiata bark after water extraction treatments. The phytotoxicity of the resulting extracted bark alone and that mixed with commercial substrates (coconut fiber, moss, peat, and composted pine) at different ratios (25 to 75 wt%) were assessed using the Munoo-Liisa vitality index (MLVI) test. For all treatments, the seed germination and growth of radish (Raphanus sativus) and Chinese cabbage (Brassica rapa) species were evaluated and compared to a commercial growing medium (peat) as a control. The optimal mixture for seed growth was determined to be 75% extracted E. globulus bark fiber and 25% commercial substrates such as peat (P), coconut fiber (C), moss (M), and composted pine (CP), as indicated by the MLVI and germination results. Two phytostimulant products, chitosan and alginate-encapsulated fulvic acid, were added to the best substrate mixture, with the purpose of improving their performance. Encapsulated fulvic acid at 0.1% w/v was effective in promoting plant growth, while chitosan at all of the concentrations studied was effective only for mixture 75E-25CP. The mixture of E. globulus fiber and commercial substrates, containing a high proportion of water-extracted fiber (75%), shows the potential to be used in the growth of horticultural crops and in the plant nursery industry.
  • No Thumbnail Available
    Item
    Valorization of Uruguayan Pinus elliottii Bark by Developing Sustainable Adhesives
    (2023) Serrentino, Paola; Santos, Jorge; Fuentealba, Cecilia; Hernandez-Mena, Laidy; Mary, Alvaro; Ibanez, Claudia Marcela
    Pinus elliottii Engelm bark is a byproduct of Uruguay's milling industry. As a circular economy strategy, it is burned in broilers for energy production. Aiming to increase the added value of the bark, this work analyzes the extraction of its tannins to use them in the development of formaldehyde-free adhesives, while evaluating whether it retains its calorific power for further energy production. The best extraction conditions (methanol at 65 & DEG;C for 2 h) were identified at a laboratory level after which they were scaled up to 50 L, which did not affect extraction yield. The Stiasny number remained above 65%, meaning the extractive was suitable for its use in adhesive formulations. The characterization of the extractives was completed with molecular weight distribution, FTIR-ATR, ABES and DSC. Finally, two formaldehyde-free adhesive formulations were developed using hexamine and glyoxal as hardeners. Their behaviors were compared through rheological analysis, DSC and ABES. It was determined that the adhesive formulations with hexamine at pHs of 8 and 10 are suitable for their use in the timber industry. It was noted that they react the best at a pressing temperature of 160 & DEG;C. After the extraction, the calorific power of the P. elliottii Engelm bark decreased by only 13%, thus remaining useful for energy production.