# Analysis of the Sugarane Biomass Use to Produce Green Hydrogen: Brazilian Case Study
## 5 Environmental Impacts and Sustainable Solutions
### Second-Generation Ethanol as a Sustainable Pathway for Green Hydrogen
#### 5.2.2 Production of Green Hydrogen Parallel to Bioethanol  
Green hydrogen can also be produced from lignocellulosic biomass through fermentation combined with integration into other energy generation systems. A key step in this approach involves the chemical pretreatment of sugarcane bagasse, which is a conventional method for breaking down lignocellulosic into its mono- and oligomeric units. These units can subsequently be bioconverted into ethanol. Commonly used agents for this pretreatment include dilute acids, alkaline solutions, organosolv reagents, and ionic liquids [68]. These pretreatment methods play a critical role in optimizing the conversion process, making it a promising pathway for sustainable hydrogen production. Lignocellulosic biomass is an abundant and cost-effective renewable resource that holds significant promise for biohydrogen production [80]. Predominantly derived from sugarcane bagasse and straw, these materials are rich in cellulose, hemicellulose, and lignin, with smaller amounts of extractives and ash [82]. This composition underscores its potential as a sustainable substrate for hydrogen production, paving the way for innovative bioenergy solutions. Lignin, a compound obtained from the delignification of lignocellulosic biomass, also plays a critical role in biohydrogen production. A study published in the _International Journal of Hydrogen Energy_ demonstrated that biohydrogen yield can be enhanced through the incorporation of lignin-mediated iron nanoparticles (FeNPs) into the fermentation medium. The study revealed that these magnetic nanoparticles significantly improved microbial activity, fostering more efficient pathways for hydrogen production compared to non-magnetic nanoparticles [83]. These findings highlight the transformative potential of nanotechnology in optimizing the biohydrogen production processes. Despite technological advancements, challenges remain in scaling up biohydrogen production from lignocellulosic biomass. According to research in the Science of The Total Environment, pretreatment methods are often inefficient and costly, leading to by-products that inhibit microbial growth and reduce hydrogen yield. For industrial viability, it is essential to redirect carbon flow towards hydrogen production while minimizing the synthesis of inhibitory by-products [84]. For biohydrogen production to be feasible, it is crucial to redirect the carbon flow toward hydrogen generation, thereby minimizing the formation of inhibitory by-products. A recent development in the application of lignocellulosic biomass involves nanoparticles with enzymatic mimetic properties, known as nanozymes. These nanozymes are increasingly being explored as enzyme substitutes across various fields, including agriculture and biofuel production [85]. According to a study published in Bioresource Technology, it is possible to develop a sustainable process for hydrogen production through the implementation of nanotechnology in combination with the consolidated bioprocessing approach from lignocellulosic biomass [86]. In this study, it was found that the combination of nanomaterials and consolidated bioprocessing approaches for hydrogen production would definitively prove commercial viability, which is an urgent need today. Another innovative approach involves the co-production of green hydrogen and bioethanol from sugarcane bagasse within a circular biorefinery framework. An article in _The Chemical Engineering Journal_ presented an integrated strategy to fully utilize raw materials for producing biohydrogen and bioethanol alongside organic agriculture. Through experiments conducted in three phases, the study demonstrated the viability of biohydrogen production using pure xylose and raw materials sourced from agricultural fields [87]. By converting xylose into biohydrogen, the process maximizes resource recovery from biomass, minimizing waste and optimizing the biorefinery system [88].