## 5 Conclusions  
This study demonstrates the feasibility of producing biochar with favorable properties using renewable and sustainable biomass, employing a simple double-chamber reactor and utilizing biomass as a source of thermal energy. The results indicate that all three types of lignocellulosic biomass provide suitable parameters for energy utilization and the production of high-quality biochar, with the biomass of acacia particularly standing out among the three.  
The results of biochar produced via slow pyrolysis at temperatures between 400 and 500 \({}^{\circ}\)C demonstrate improvements over the values obtained from the original biomass. Biochar yields ranged between 30% and 40%, with a high fixed carbon content, showing the highest value at 77 \(\pm\) [2.51]% with acacia biomass. The H/C ratio of 0.03 in all three biochars, compared to 0.13 in the biomass, indicates suitable aromaticity and maturation. The main inorganic elements in the three biochars show an increase compared to the original biomass. The high presence of calcium (Ca) and potassium (K) evidence an advantage for use in soil.  
The high fixed carbon values enable the biochar utilization for soil remediation and enrichment, carbon sequestration, as filtering elements or another versatile application, as composing organic solid waste, decontaminating water and wastewater, serving as catalysts and activators, as well as in electrode materials and modifiers. The studied lignocellulosic biomass material, along with the selected working conditions and technologies, facilitated the production of high-quality biochar.  
Figure 13: Cationic analysis of biomass and biochar material.  
**Author Contributions:** O.G.-P.: conceptualization, methodology, validation, formal analysis, investigation, writing--original draft preparation, supervision. L.O.T.: conceptualization, methodology, validation, resources, writing--original draft preparation, funding acquisition, supervision. A.V.T.: methodology, formal analysis. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by Operational Group for the development of new products, practices, processes, and technologies in the agroforestry field, co-financed with the European Agricultural Fund for Rural Development (EAFRD) within the framework of the Rural Development Program (PDR) of Galicia 2014-2020.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The data are available to interested parties upon explicit request to the corresponding author. Data will be available within five years of the publication date.  
**Acknowledgments:** The authors thank all the organizations involved as well as the scientific colleagues who in some ways have contributed to this work. Special thanks to GO BioforePlus and GO Ecochar groups, involved in the national projects FEADER 202/031A and FEADER 2023/011B, respectively.  
**Conflicts of Interest:** The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.