Felipe Fernando Furlan

Biodiesel is a key fuel for a zero-carbon future. Enzymatic synthesis using renewable materials can make it even more environmentally friendly. However, high enzyme costs and limited reuse hinder its economic feasibility. This study assessed the techno-economic and environmental performance of different processes for ethyl ester biodiesel production. The scenarios evaluated include: transesterification of soybean degummed oil using free and immobilized Eversa Transform 2.0, chemical alkaline catalysis of soybean oil, and transesterification of waste oil using ET. The main metrics were net present value and global warming potential. Results showed that the free enzyme outperformed the immobilized enzyme economically. However, chemical catalysis had an NPV nearly double that of the best free enzyme option. Sensitivity analysis revealed that enzyme cost and reuse rate were critical to net present value. Transesterification of waste oil with enzyme reuse had the lowest GWP (4.21 g \mathrm{CO_{2eq}} /MJ), making it the most environmentally favorable scenario. While life cycle assessment indicated lower global warming potential for enzymatic catalysis, further study is needed on emissions from enzymes. Depending on the enzyme and reuse rate, chemical catalysis might result in lower overall emissions. Integration with the biorefinery makes large-scale enzymatic biodiesel production economically viable and with low \mathrm{CO_{2eq}} emissions.

This work addresses the technical–economic–environmental analysis of a 1G2G ethanol integrated process using immobilized recombinant Saccharomyces cerevisiae and crude sugarcane bagasse acid hydrolysate mixed with molasses. Three case studies were evaluated and compared with the traditional 1G plants. The minimal ethanol-selling price and the life cycle assessment using CML-IA midpoint indicators were chosen as the economic and environmental metrics, respectively. The values found for the ethanol-selling price ranged from 472.92 USD/m³ to 966.53 USD/m³ for the integrated case studies. Compared to the average sales value of 1G ethanol (673.48 USD/m³), the first and second case studies were interesting for their economic viability, while the third case study would require a 43.5% increase in the price of ethanol to achieve production profitability. In the environmental assessment, the integrated 2G ethanol processes of the first and third case studies allowed for the increase in ethanol production per ton of sugarcane processed without decreasing the environmental performance of the process. The third case study presented the lowest environmental impact indicators, except for global warming potential and photochemical oxidation categories, highlighting the importance of the development of biomass pretreatment strategies with lower carbon footprint. The strategy of integrating the 2G process into a 1G ethanol biorefinery offers interesting economic and environmental values, allows the use of hemicellulose, and contributes to the development of 2G processes in sugarcane biorefineries and to the sustainability of the processes.

Hyaluronic acid is a biopolymer that has gained attention from both researchers and the public since its discovery in 1934. In 2022, its global annual demand was 667 MT, with a market value of 9.4 billion dollars and an expected compound growth rate of 7.7% from 2024 and 2030. Such popularity lies in its many applications, which ranges from pharmaceutical to Tissue Engineering. Its molecular weight (MW) determines which application hyaluronic acid is better suited for: high MW (over 1 MDa) is used in medical applications such as osteoarthritis and ophthalmology, and low MW (less than 0.05 MDa) are suited for moisturizing cosmeceuticals. This makes hyaluronic acid molecular weight an important parameter for its production. The first industrial process was based on extraction from rooster combs. However, it shifted toward microbial production with Streptococcus zooepidemicus. Studies focus on improving its production and tailoring its molecular weight by accessing optimum temperature, pH, aeration, agitation, carbon, and nitrogen sources concentration and origin. his review aims to provide an overview of the current knowledge on the effects of metabolic and environmental factors in microbial hyaluronic acid production. The review shows that there has been extensive research in optimizing cultivation medium composition, temperature, pH, and aeration between 2018 and 2023, but further studies are required to optimize the metabolism of S. zooepidemicus towards maximum biopolymer production and molecular weight.

Succinic acid is an essential component of the chemical industry. Traditionally produced from fossil resources, its sustainable production using renewable resources faces challenges due to the complexities of cultivation and purification. This study assessed the environmental impacts of succinic acid production from sugarcane through a life cycle analysis and compared it with three other scenarios: using sorghum, apple pomace, and the traditional chemical route. Employing the ReCiPe midpoint methodology with a cradle-to-gate approach, the analysis highlighted significant environmental impacts linked to the agricultural stage in the sugarcane process. The use of pesticides, fertilizers, and energy demand resulted in elevated impacts compared to other stages of the process. The other scenarios also presented strong contributions in the purification stages. The production from sugarcane proved advantageous compared to other scenarios, minimizing impacts in 6 out of 10 categories. It is evident that the selection of the correct biomass is crucial for process sustainability, and the use of second-generation inputs can help reduce impacts in the agricultural stage. However, advancements in the fermentation stage are necessary, along with a reduction in the complexity of the purification steps. This study emphasizes the potential of renewable succinic acid production from sugarcane juice in the Brazilian scenario. Utilizing this process could reduce succinic acid’s environmental impacts by 70% to 99% compared to the petrochemical route. The process should be considered as a sustainable alternative to be included in the portfolio of biorefineries, enhancing factory profitability.

Xylooligosaccharides (XOS) are nondigestible compounds of great interest for food and pharmaceutical industries due to their beneficial prebiotic, antibacterial, antioxidant, and antitumor properties. The market size of XOS is increasing significantly, which makes its production from lignocellulosic biomass an interesting approach to the valorization of the hemicellulose fraction of biomass, which is currently underused. This review comprehensively discusses XOS production from lignocellulosic biomass, aiming at its application in integrated biorefineries. A bibliometric analysis is carried out highlighting the main players in the field. XOS production yields after different biomass pretreatment methods are critically discussed using Microsoft PowerBI^® (2.92.706.0) software, which involves screening important trends for decision-making. Enzymatic hydrolysis and the major XOS purification strategies are also explored. Finally, the integration of XOS production into biorefineries, with special attention to economic and environmental aspects, is assessed, providing important information for the implementation of biorefineries containing XOS in their portfolio.