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Improving bio-oil fractions through fractional condensation of pyrolysis vapors from Eucalyptus globulus biomass residues in a prototype auger reactor
Publication . Vilas-Boas, A.C.M.; Tarelho, L.; Marques, C.C.; Moura, J.M.O.; Santos, M.C.; Paradela, Filipe; Nunes, M.I.; Silvestre, A.J.D.
ABSTRACT: Bio-oil produced from the pyrolysis of lignocellulosic biomass has potential as a biofuel or chemical precursor. However, its valorization is hindered by its complex composition, high water concentration, and the presence of oxygenated compounds. Operational strategies are therefore required to improve its quality. This study evaluated the technical feasibility of fractional condensation as an alternative to conventional single-stage condensation of vapors produced from pyrolysis of residual Eucalyptus globulus biomass to collect bio-oil fractions with improved properties. The process was carried out using a prototype-scale auger reactor with continuous operation. The fractional condensation system comprised four sequential condensation stages operating at progressively lower temperatures: 140, 100, 80, and 0 degrees C. The collected bio-oil fractions were analyzed in terms of product yields, water separation efficiency, elemental composition, heating value, and the presence of volatile and semi-volatile compounds. The results demonstrated that fractional condensation achieved total bio-oil yields comparable to those obtained with the single-stage condensation system, while enabling the recovery of bio-oil fractions with lower water concentration, higher carbon concentration and increased heating value. Notably, the first condensation stage collected heavy fractions with water concentration between 3 % and 6 %wt., oxygen concentration between 17 % and 21 %wt., and carbon concentration between 69 % and 72 %wt., resulting in O/C molar ratios between 0.17 and 0.22, values close to those of biodiesel. These fractions exhibited lower heating values of up to 31 MJ/kg, surpassing those of conventional liquid biofuels such as biomethanol and bioethanol. These findings highlight the potential of fractional condensation of pyrolysis vapors from residual biomass from Eucalyptus globulus as an effective strategy to produce bio-oil with properties more suitable for direct energy use or as an intermediate feedstock for biofuels synthesis. Further research is recommended to optimize the condensation stages and assess the long-term stability of recovered fractions.
Proteolytic Bacillus sp. Isolation and Identification from Tannery Alkaline Baths
Publication . Lageiro, Maria Manuela; Simões, Fernanda; Alvarenga, Nuno; Delgado dos Reis, Alberto José
ABSTRACT: The application of microbial alkaline proteases holds significant potential for eco-sustainable industrial processes by reducing chemical usage and lowering the costs of effluent treatment. In the search for novel proteases with industrial relevance, several microbial strains were isolated from alkaline baths of the Portuguese tannery agroindustry. The most promising protease-producing strains were selected for identification and further study. Two isolates demonstrated the highest proteolytic activity, reaching 0.51 +/- 0.01 U mL-1 and 0.70 +/- 0.01 U mL-1 after 7.5 h of submerged cultivation in nutrient broth. Based on API biochemical tests, molecular biology techniques, and GC-FAME analysis of membrane lipids, the isolates were identified as Bacillus subtilis and incorporated into INIAV's collection of industrial microbial cultures as B. subtilis CCMI 1253 (BMR2) and B. subtilis CCMI 1254 (BMR1). The most promising protease producer, B. subtilis CCMI 1253 (BMR2), exhibited a maximum specific growth rate of 0.88 +/- 0.10 h-1. The proteases produced exhibited good extracellular proteolytic activity, with adaptability to industrial conditions, indicating their suitability for agroindustry applications such as leather making, detergent formulations and the treatment of effluents and protein residues. The results support the potential of microbial proteases as valuable tools in the bioeconomy and green chemistry.
Social Awareness as a Catalyst for Biochar Adoption in the Agricultural and Forestry Sectors
Publication . Janiszewska-Latterini, Dominika; Ortigueira, Joana; Lopes, Tiago; Gościańska-Łowińska, Julia; Augustyniak-Wysocka, Dobrochna; Leszczyszyn, Ewa; Nobre, Catarina
ABSTRACT: Biochar, a carbon-rich material produced from the pyrolysis of organic matter, has garnered attention for its potential agricultural and environmental benefits, including soil improvement, enhanced crop yields and climate change mitigation. Despite its promise, biochar adoption has been hindered by limited social awareness, particularly in industrialised countries. This review explores the factors influencing biochar's acceptance in agriculture and forestry, focusing on the social aspects that affect its integration. A systematic literature review was conducted to identify studies on social awareness and acceptance, revealing significant barriers such as a lack of knowledge among farmers, high production costs and insufficient infrastructure. In industrialised countries, while technical research on biochar has progressed, farmers often remain unfamiliar with its benefits, and resistance to adoption is common. Studies show that social factors such as age, education level and access to funding play a crucial role in biochar adoption. Furthermore, a lack of government incentives and unclear regulatory frameworks exacerbate the challenge. Conversely, studies from lower-income countries suggest that small-scale, cost-effective biochar production systems may hold promise. The review also identifies strategies to enhance biochar's social acceptance, including targeted education programs, financial incentives and clearer regulatory standards. Despite varying levels of social awareness, the literature suggests that with increased outreach, biochar could significantly contribute to sustainable agricultural practices globally. This review underscores the need for further research into the social dimensions of biochar adoption and the implementation of policies to foster its widespread use.
Miragaia longicollum MG 4863: New fossil and historical evidence from the most complete stegosaur from Europe
Publication . Costa Pinto, Francisco; Maidment, Susannah; Sequero, Cristina; Crespo, Vicente D.
ABSTRACT: Additional historical data regarding the original finding and excavation (circa 1958-1959) of the Miragaia longicollum stegosaur MG 4863 has been identified (including field notes and the complete field map), allowing a better understanding of its stratigraphic context. Additionally, osteological material that was previously partially encased in matrix was fully prepared and restored, including anterior and posterior caudal vertebrae, metacarpals, and five semi-complete dorsal vertebrae (the latter being the most significant addition, as these are the only skeletal elements shared by all type specimens of dacentrurine taxa). New anatomical information from these additional elements provides further evidence that M. longicollum is distinct from the closely related Late Jurassic stegosaur Dacentrurus armatus from England (demonstrated mainly by various caudal differences). The newly prepared material further completes what was already the best reference specimen among the Dacentrurinae clade, as well as Stegosauria in Europe during the Late Jurassic, increasing its value to better understand these contexts in future studies.
Foresighting Scenarios for Green Hydrogen in Portugal: Systematization of Potential Futures and Identification of Bottlenecks and Constraints
Publication . Vieira, Mário; Alves, Marco; Simoes, Sofia; Quental, Lídia; Catarino, Justina; Ribeiro Pinto, Paulo Jorge; Oliveira, Paula; Simões, Teresa
ABSTRACT: The use of green hydrogen has emerged as a promising avenue for facilitating the decarbonization of society. In this study, the potential futures of green hydrogen in Portugal, a key player in Europe's energy transition, are explored. Utilizing General Morphological Analysis combined with advanced clustering, the various political, social, and technological elements are analyzed to create a multifaceted view of the sector's future. This results in seven distinct scenario clusters, each offering unique insights into the challenges and opportunities for green hydrogen. The scenarios span a range of outcomes, from rapid growth fueled by strong policy support and technological advancements to more measured development due to economic or infrastructural hurdles. This study intends to provide stakeholders a deep understanding of the factors influencing green hydrogen's role in Portugal's push towards a sustainable energy landscape by 2030. These results provide a basis for the development of new projects and research directions, providing them with the necessary knowledge to make informed decisions. Moreover, this study will contribute to decision support by facilitating actions aimed at fostering the appropriate development of green hydrogen.