SOUTHERN JOURNAL OF SCIENCES

Demand for diversified biodiesel feedstocks is high and increasing, but few are viable for large-scale production, and many of those selected compete with other sectors of the chemical industry. To improve energy and environmental sustainability, fatty acids from waste oils that are improperly disposed of and pollute the environment can be used for transesterification reactions. However, they need treatment to achieve high conversion rates. In this context, the aim of this work was to perform and analyze the treatment of residual frying oil with the evaporation and entrainment process, aiming at its use as raw material to obtain biodiesel (methyl esters) by a transesterification reaction. The physicochemical properties of the residual oil after treatment were characterized by moisture content, pH and the acidity, saponification, iodine, and peroxide index. The conversion rate of the residual oil to methyl esters was determined by 1H NMR analysis. After the treatment, the method of analysis of variance showed that the oil obtained a significant reduction of the saponification, iodine, peroxide and acidity indexes, being the acidity reduced from 9.36 to 7.85 mg KOH g-1. The moisture content of 0.733% and elevation of pH to 8.0. The conversion rate of fatty acid biodiesel of residual oil was 79.3 %, lower value of standards norms (ASTM, 2005; EN, 2008; ANP, 2014), showing that the assigned methodology for frying residual oil is inefficient in biodiesel production.

Due to their diverse properties, plastic materials are used in numerous sectors. It is possible to produce different articles and plastic objects with reduced costs, being more accessible to the population. Conventional plastics are obtained from petroleum-derived raw materials, a non-renewable resource in which their extraction and refining process cause major environmental impacts. The production of plastic reaches a level of approximately one hundred and forty million tons per year, and the disposal of these materials is increasing, generating a high rate of waste and leading to an increase of pollution since the decomposition of these materials lasts about five hundred years old. Conventional plastics can be replaced by bioplastics, a material obtained from renewable raw materials such as potatoes, cassava, maize, and which, when disposed of under favorable conditions, decomposes faster, as during its degradation process at least one step occurs. Through the metabolism of organisms present in the environment. Starch has been widely used in the production of biodegradable packaging, so the objective of this work was to produce a biodegradable bioplastic from the potato starch. Potato starch, glycerin, hydrogen peroxide, distilled water, and commercial agar were used to produce the bioplastic. Bench-scale bioplastics had good organoleptic characteristics, similar in appearance to a conventional plastic obtained from petroleum. The thickness, moisture content, and solubility of the bioplastics were analyzed, as well as their fruit preservation capacity. The samples produced were rigid and with good resistance.

Background: Scientific conferences play a vital role in knowledge exchange and collaboration across disciplines. Building on the success of its 2022 inaugural event, the Second Southern Science Conference (SSCON 2024) aimed to expand international scientific collaboration while addressing contemporary challenges in sustainability and research methodology. Aims: To evaluate the effectiveness of a hybrid conference format in facilitating global scientific collaboration and to showcase cutting-edge research across multiple disciplines, with particular emphasis on sustainability and technological innovation in Latin America. Methods: The conference implemented a hybrid format combining in-person and virtual attendance. Over three days, 38 lectures were presented by renowned researchers, covering key topics including materials science, environmental sustainability, chemical processes, and regional development. Participation metrics and collaboration patterns were analyzed to assess the conference's impact. Results: The conference achieved significant participation with 242 contributing authors from 13 countries across four continents. Notable research presentations included advances in laser surface modification techniques, geotechnology applications in biofuel production, sustainable silica synthesis from biomass, and green valorization of tropical seeds. The conference produced 66 approved papers, with most involving 2-5 collaborators. Discussion: The hybrid format proved effective in removing geographical barriers and promoting global engagement. The strong representation from Latin American institutions highlighted the region's growing influence in international scientific discourse. Key research presentations demonstrated innovative approaches to sustainability challenges, particularly in waste utilization and environmental technology. Conclusion: SSCON 2024 successfully evolved from its predecessor, demonstrating the effectiveness of hybrid conferencing in fostering international scientific collaboration. The conference established itself as a vital platform for knowledge exchange, particularly in sustainability and technological innovation, while identifying areas for future improvement such as extended submission timelines and permanent management structures.