Biodiesel can be produced from vegetable oils, animal fats, frying oils, and from microorganism-synthesized oils. These sources render biodiesel an easily biodegradable fuel. The aim of this work was to perform an advanced bibliometric analysis of primary studies relating to biodiesel production worldwide by identifying the key countries and regions that have shown a strong engagement in this area, and by understanding the dynamics of their collaboration and research outputs. Additionally, an assessment of the main primary feedstocks employed in this research was carried out, along with an analysis of the current and future trends that are expected to define new paths and methodologies to be used in the manufacture of biodegradable and renewable fuels. A total of 4586 academic outputs were selected, including peer-reviewed research articles, conference papers, and literature reviews related to biodiesel production, in the time period spanning from 2010 to 2021. Articles that focused on feedstocks for the production of biodiesel were also included, with a search that returned 330 papers. Lastly, 60 articles relating to biodiesel production via sewage were specifically included to allow for an analysis of this source as a promising feedstock in the future of the biofuel market. Via the geocoding and the document analyses performed, we concluded that China, Malaysia, and India are the largest writers of articles in this area, revealing a great interest in biofuels in Asia. Additionally, it was noted that environmental concerns have caused authors to conduct research on feedstocks that can address the sustainability challenges in the production of biodiesel.

A theoretical and experimental study was carried out on the biocatalytic production of babassu biodiesel through enzymatic hydroesterification. The complete hydrolysis of babassu oil was carried out using a 1:1 mass solution at 40 °C for 4 h using 0.4% of lipase from Thermomyces lanuginosus (TLL). Then, with the use of Eversa^® Transform 2.0 lipase in the esterification step, a statistical design was used, varying the temperature (25–55 °C), the molar ratio between free fatty acids (FFAs) and methanol (1:1 to 1:9), the percentage of biocatalyst (0.1% to 0.9%), and the reaction time (1–5 h) using the Taguchi method. The ideal reaction levels obtained after the statistical treatment were 5 h of reaction at 40 °C at a molar ratio of 1:5 (FFAs/methanol) using 0.9% of the biocatalyst. These optimal conditions were validated by chromatographic analysis; following the EN 14103 standard, the sample showed an ester concentration of 95.76%. A theoretical study was carried out to evaluate the stability of Eversa with FFAs. It was observed in the molecular docking results that the ligands interacted directly with the catalytic site. Through molecular dynamics studies, it was verified that there were no significant conformational changes in the studied complexes. Theoretical and experimental results show the feasibility of this process.

Lignocellulosic biomasses are used in several applications, such as energy production, materials, and biofuels. These applications result in increased consumption and waste generation of these materials. However, alternative uses are being developed to solve the problem of waste generated in the industry. Thus, research is carried out to ensure the use of these biomasses as enzymatic support. These surveys can be accompanied using the advanced bibliometric analysis tool that can help determine the biomasses used and other perspectives on the subject. With this, the present work aims to carry out an advanced bibliometric analysis approaching the main studies related to the use of lignocellulosic biomass as an enzymatic support. This study will be carried out by highlighting the main countries/regions that carry out productions, research areas that involve the theme, and future trends in these areas. It was observed that there is a cooperation between China, USA, and India, where China holds 28.07% of publications in this area, being the country with the greatest impact in the area. Finally, it is possible to define that the use of these new supports is a trend in the field of biotechnology.

In this study, the energy potential of five types of biomass waste from cultures of banana (Musa spp.), cashew (Anacardium occidentale L.), babassu coconut (Orbignya speciosa), mango (Mangifera indica), and several flowers from the central hinterland of Ceará, Brazil was evaluated, to investigate their applicability as potential sources of alternative energy, for example, Briquettes. Many countries have been looking for new types of energy that are sustainable and clean, and biomass energy has been attracted attention in the last years because, is a renewable resource that, can be transformed in gaseous, liquid, and solid fuel. However, there are still many points that need investigation, for example, physicochemical properties and analytical characterization, energy efficiency, and cost. Therefore, the evaluation of the energy potential of biomass derived from a specific region is necessary. The thermal and oxidative behavior of the samples were evaluated by thermogravimetric (TG-DTG) analysis in atmospheres of nitrogen (N2) and synthetic air. For biomass characterization, the following analyses were done: immediate chemical analysis and high calorific value. The results showed that all the samples of biomass residues displayed high calorific values (>11 MJ/kg) and the immediate analysis showed that these residues displayed acceptable reactivities with a high volatile content (>70%). Average percentages were calculated for each parameter, and the following relationships were obtained for the different samples of biomass waste: Moisture (M): Mnitrogen > Mair; Volatile Matter (VM): VMair > VMnitrogen, and Ash Content (AC): ACair > ACnitrogen. The differences in the temperatures and decomposition rates of cellulose and hemicellulose enabled the investigation of the influence of oxidative and inert gas (synthetic air and nitrogen) upon the characteristics of waste decay, as well as inferences regarding the use of the thermogravimetric techniques in the study of the decomposition of different biomasses, for possible application as energy sources, as a quick, effective, and accurate tool.