Abstract Global reliance on fossil fuels has created urgent economic and environmental challenges, yet large‐scale use of algal biomass remains limited by production costs. Industrial scaling is constrained by inefficient harvesting and the technical challenges of processing recalcitrant cell walls. This review proposes that Chlorella vulgaris ‐based biorefineries can become economically viable through integrated multiproduct valorization aligned with circular economy principles. A synthesis of literature, patents, and techno‐economic studies – supported by bibliometric analyses of the Web of Science and WIPO PATENTSCOPE – highlights multidisciplinary trends spanning biology, engineering, and market dynamics. Academic research primarily focuses on biofuels, whereas patent trends emphasize nutraceutical and cosmetic applications. This divergence reveals opportunities for hybrid cascade‐extraction approaches that integrate biotechnology, artificial intelligence‐assisted process optimization, and the valorization of residue into biochar. High‐value co‐products, such as lutein and astaxanthin, support projected profit margins of 40% to 45%, a 3.5‐ to 4.5‐fold increase over biodiesel‐only routes, while potentially offsetting up to 4.1 million t CO 2 annually. Future development could include metabolic engineering (e.g., CRISPR/Cas9) to enhance yields, pilot‐scale demonstrations in semi‐arid regions using brackish water and industrial CO 2 streams, and measures to address regulatory, investor, and certification challenges. Ultimately, C. vulgaris ‐based biorefineries can foster circular bioeconomies, recover nutrients from waste, and leverage the expanding global market, positioning the species as a versatile and profitable platform for sustainable technological transitions.

Abstract This study integrates kinetic modeling in AQUASIM with SuperPro Designer® simulation to investigate the techno‐economics of bioethanol production from microalgae. For the first time, kinetic models supported by SuperPro Designer® were developed for bioethanol production from enzymatic hydrolysis products of mixed microalgae. Comparative techno‐economic evaluations were conducted on dry and wet processing routes for microalgae. Key economic indicators (net present value, internal rate of return [IRR], payback time) and variable sensitivities were investigated. The agreement of experimental and simulation results using SuperPro Designer® showed the highest reducing sugar yield with cellulase (50 °C, pH 5), alpha‐amylase (70 °C, pH 6), at the optimal initial concentration of 50 g L −1 . Simultaneous enzyme addition accelerates hydrolysis and improves process economics. The techno‐economic analysis revealed that the wet biomass strategy, by removing harvesting, drying, and milling steps, reduced both CAPEX and OPEX by $1000 per batch. This modification also reduced the production cycle from 209.1 to 154.3 h. Sensitivity analysis found that ±5% changes in bioethanol price and ±10% shifts in annual throughput caused corresponding variations in IRR and payback time. Despite these changes, the wet biomass strategy consistently maintains an IRR above the economic threshold (10%). These findings underscore the superior economic viability of the wet biomass strategy for industrial bioethanol production.

Abstract The growing reliance on edible oils for biodiesel production raises concerns regarding feedstock availability and cost volatility. Palm stearin (PS), a by‐product of palm oil fractionation with reduced demand in food applications, offers an attractive alternative feedstock for biodiesel production. In this study, biodiesel was produced from PS using a continuous deglycerolization reactor (CDR), which removes glycerol during transesterification. The optimal process condition was a methanol–oil molar ratio of 5:1, a potassium methoxide (KOCH 3 ) catalyst loading of 1.2 wt%, a mixing speed of 250 rpm and a glycerol removal rate of 0.25 L h −1 . Under these conditions, the CDR produced high‐quality biodiesel with an ester content of 97.23 wt% and a yield of 98 wt%. An economic assessment indicated a positive net present value, an internal rate of return above 8% per year, and a payback period of 1.12 years. Sensitivity analysis showed that economic performance is influenced by production cost and biodiesel selling price, with a break‐even selling price of US$0.99 L −1 . The combination of reduced methanol consumption and the use of lower‐cost PS support the economic viability of the proposed process.

Abstract Post‐harvest agricultural residues in Latin America are commonly underutilized, leading to greenhouse gas emissions and lost opportunities for bio‐based value creation. This study tests the hypothesis that decentralized, farmer‐scale pyrolysis technologies can deliver comparable agronomic benefits while exhibiting distinct techno‐economic and climate performance under field conditions. Two biochar production technologies, top‐lit up‐draft (TLUD) and Kon‐Tiki kilns were evaluated using corn cob residues as soil‐amending bioproducts at a 1%(w/w) application rate. Both biochars were non‐phytotoxic, exhibiting radish germination rates above 90% and no inhibition of radicle elongation. The TLUD biochar developed 21% higher microporosity than Kon‐Tiki, indicating enhanced surface functionality for soil–plant interactions. Field application significantly improved soil properties relative to the control, increasing pH by 1.9 units, electrical conductivity by 1.8‐fold, organic matter by 1.3‐fold, and cation exchange capacity by 1.6‐fold. These changes resulted in higher plant nutrient uptake, with foliar potassium and phosphorus concentrations increasing by 1.3‐ and 1.7‐fold, respectively. The TLUD‐derived biochar consistently outperformed Kon‐Tiki in nutrient delivery, consistent with its higher surface area and fixed‐carbon content. Integrating agronomic outcomes with net CO 2 e‐based techno‐economic performance reveals trade‐offs between biochar quality, nutrient delivery, capital requirements, and climate benefits that cannot be inferred from laboratory‐scale experiments. Techno‐economic analysis showed that both technologies generate positive net CO 2 e benefits in situ , with TLUD requiring lower initial investment (>900€ less than Kon‐Tiki), while both systems converge in profitability after the first production cycle. These findings demonstrate that integrated field‐scale assessment is essential to identify decentralized biochar systems that are agronomically effective, economically viable, and climate relevant.

Abstract The present work sought to broaden the repertoire of proteolytic biocatalyst formulations by producing, purifying, characterizing, and identifying suitable immobilization carriers for an extracellular protease from the filamentous fungi Periconia byssoides . Enzyme production was carried out through submerged fermentation using two different growth media. The peptone‐containing medium proved to be the most suitable for producing extracellular protease. The crude enzyme was partially purified by 70% ethanol precipitation to enable subsequent biochemical characterization and formulation studies. A Doehlert‐type design of experiments was used to determine the optimal pH and temperature of the enzyme, resulting in a pH of 6.4 and a temperature of 70 °C. To evaluate the influence of salts on enzyme activity, various salts were tested at concentrations of 0.1 and 0.01 m . At 0.1 m , CaCl 2 , MgCl 2 and NH 4 Cl inactivated the enzyme. At 0.01 m , BaCl 2 increased the catalytic activity by 6% whereas CaCl 2 and NH 4 Cl inactivated the enzyme. The kinetic parameters of the enzyme were estimated using the Michaelis–Menten equation, with casein as the substrate, at various concentrations. K m and V max were determined to be 0.23 mg mL −1 and 1.26 U mg −1 protein, respectively. A preliminary screening to identify the most efficient carrier for protease immobilization was performed using eight commercial carriers: silica gel, celite 545, chitosan, MAT 540, CPC 27709, Purolite Lifetech ECR8806F, ECR8204F, and ECR1090F. Among these, MAT 540 exhibited 49.93% immobilization yield and 90% protein retention. Overall, this work not only characterizes an extracellular P. byssoides protease but also identifies a promising carrier for its immobilization, supporting the development of an active and stable biocatalyst for future biotechnological applications.

Abstract The increasing global demand for sustainable fuels has heightened interest in lignocellulosic biomass conversion to ethanol. This study presents a technoeconomic and life cycle assessment (LCA) of novel one‐pot ethanol production from sugarcane bagasse using microwave‐assisted ternary deep eutectic solvent (DES) (choline chloride:ethylene glycol:nickel chloride hexahydrate in a molar ratio of 1:2:0.016) pretreatment. The process included microwave‐assisted DES pretreatment, enzyme hydrolysis and fermentation in a one‐pot multistep approach, followed by downstream separation and purification. A combination of process modeling from experimental data and Aspen Plus simulation for downstream separation was applied to the analysis of a plant with a capacity to produce 100 t of ethanol per day. The plant was assumed to be annexed to a sugar mill. OpenLCA 2.0 was used to construct the LCA model to analyze and quantify the environmental impact associated with producing 1 kg of ethanol as the functional unit. Further, to increase the robustness and reliability of the process, different scenarios and sensitivity analyses were studied. The base case considered was 10% solid loading at pretreatment and no recycling of pretreatment solvent, which resulted in a production cost of 1098 USD per t with a payback period of 5 years. The sensitivity analysis identified process improvement opportunities where increasing solid loading and DES loading could significantly reduce production cost by 30% and global warming potential, by 91%. Economic assessment revealed that increasing plant capacity would significantly reduce the production cost per t of ethanol, highlighting the benefits of scaleup in improving financial viability. These results underscore the value of integrated process optimization in enhancing bioethanol production while mitigating the associated environmental burden.

Abstract The prolonged start‐up period of high‐rate anaerobic anaerobic reactors represents a critical techno‐economic bottleneck, and this study demonstrates that targeted bioadditive conditioning offers an effective strategy to accelerate granulation while simultaneously enhancing methane yields at laboratory and pilot scales in two 2 L lab‐scale upflow anaerobic sludge blanket reactors (R1: multivalent cation addition, R2: chitosan addition) and subsequently, a 20 L pilot‐scale reactor, respectively. Laboratory‐scale experiments demonstrated that chitosan‐based conditioning shortened granulation time by approximately 15 days compared with conventional operation, whereas multivalent cations primarily improved microbial diversity and structural stability. When these strategies were combined and evaluated in a 20 L pilot‐scale reactor, biomass concentration increased by 126% and methane content reached 74.5% within 52 days, indicating accelerated commissioning and earlier energy recovery. The confirmation of this hypothesis is economically relevant, as reduced start‐up periods directly translate into faster cash‐flow generation, lower financial risk during early operation, and improved feasibility of capital‐intensive anaerobic treatment facilities. Beyond process intensification, the results reveal an overlooked interdisciplinary connection between polymer‐assisted microbial aggregation, granule‐scale ecology, and reactor‐scale techno‐economic performance. Metagenomic analysis revealed that chitosan favored the dominance of extracellular polymeric substance‐producing genera such as Methanobacterium and Clostridium , while multivalent ions supported greater microbial diversity. Overall, this work provides a scalable and cost‐effective framework for improving anaerobic digester start‐up performance, offering clear industrial relevance and a basis for future integration with digital twin‐based optimization and investment decision‐support tools. Last but not least, this study highlights the synergistic impact of bioadditives and reactor scale on anaerobic sludge granulation and system performance.

Abstract The cladodes, or ‘leaves’, of a cactus, Opuntia ficus‐indica , are a traditional human food in central Mexico, with an annual production of 900 000 tons. Approximately 5% of the crop is lost during manual harvesting. This research deals with the fermentation of O. ficus‐indica and subsequent methane production. A semicontinuous fermenter was operated at 35 °C with solid retention times (SRTs) of 15, 10, and 5 days. The fermentation products were identified through gas chromatography. The digestates from the different fermentations were used to determine the specific methane production (SMP). As the primary product of fermentation (accounting for 50% of total metabolites), ethanol was identified during the first 14 days, followed by acetic acid. Ethanolic fermentation was caused by naturally occurring yeast. Butyric acid was predominant for a 5 day SRT. During fermentation, carbohydrate removal ranged from 73 to 86%. Solid retention time is crucial in O. ficus‐indica pre‐fermentation since under‐ or over‐fermentation can reduce specific methane production compared with unfermented O. ficus‐indica . The highest SMP was observed in the digestates from the 10 day SRT, at 928 NmL g VS −1 , followed by unfermented O. ficus‐indica , at 866 NmL g VS −1 . Lower SMP was achieved with SRTs of 5 and 15 days, at 580 and 525 NmL g VS −1 , respectively. Endogenous methane production increased with initial substrate concentration.

Abstract Lantana camara is noxious weed that has affected habitats across the world and is named among the top 10 most invasive species. Native to the Americas, the plant thrives under tropical conditions and has invaded forest and urban areas, affecting plant and animal life. Efforts to control the spread of L. camara have not been successful. In this study, we have converted L. camara stems into biocomposites using the stems as reinforcement and polypropylene as the matrix. Composites were prepared through compression molding at 170°C with an intention to use the biocomposites as replacement for plywood. Composites were made with varying ratios (up to 90% (w/w) L. camara stems) of the reinforcement and matrix and changes in mechanical properties, thermal and acoustic resistance and morphology were studied. Addition of 70% (w/w) stems provided highest tensile strength of 11.4 MPa and modulus of 531 MPa, considerably higher than most biocomposites containing biobased materials. Increasing ratio of the stems in the composites supressed sound absorption at varying frequencies and also decreased thermal conductivity to different extents depending on the amount of L. camara in the composites. Properties of the L. camara composites obtained in this research are suitable for civil (false roofing), automotive (interior panels, headliners) and other applications including replacement of plywood based products, packaging materials etc. Lantana stems offer an inexpensive, sustainable resource for biocomposites and at the same time could be a prudent approach to manage the obnoxious weed.