# Biochar from Agro-Forest Residue: Application Perspective Based on Decision Support Analysis
## 1 Introduction
The estimated activation energy (\(E\)) of the devolatilization stage is 78.15 kJ/mol. The same authors confirmed that the maximum gas yield is obtained at 500 \({}^{\circ}\)C, while the maximum oil yield is at 400 \({}^{\circ}\)C.  
Currently, biochar is of particular interest to a wide range of research fields and economic sectors [23; 24]. The properties of biochars are investigated for soil improvement [25; 26; 27]. According to [28; 29], biochar application is a promising and effective method for remediation of various contaminations including heavy metals in soil. The application of biochar as catalyst for biodiesel production is proposed by [30; 31]. Investigations of biochar obtained from pyrolyzed almond shells show encouraging results in producing sustainable and cost-effective electrodes for bioelectrochemical systems, as they perform comparably to carbon felt electrodes [32]. Similar are the findings of [PERSON] et al. [33] who examine walnut shell biochar. The material was used to prepare the microbial fuel cell (MFC) electrode. The authors conclude that the investigated biochar is a promising MFC electrode material. However, the specific properties of the derived biochar strictly depend on the feedstock used, the chosen conversion technology, and the operating conditions [34]. The products' characteristics are evaluated using different analytical methods and procedures [35], thus, providing valuable data allowing to determine the possible aspect of biochar utilization [36]. According to [PERSON] et al. [37] and [PERSON] [38], very important advantages of biochar combustion are the reduced emissions of air pollutants and the opportunity for increased fuel diversification. Biomass pyrolysis or carbonization normally reduces the volatile matter by between 30 and 60%, depending on the applied conditions. This considerably influences combustion emissions. [PERSON] and [PERSON]. [39] burned pulverized biochar in a Drop Tube Furnace (DTF) and observed a significant reduction in particulate matter's emissions in comparison to feedstock combustion. Current research is focused on detailed characterization and kinetic analyses of biomass combustion [22; 40; 41; 42; 43]. Increasing interest in biochar combustion was also identified [44; 45]. Biomass is associated as a potential renewable source of energy merely due to its wide availability. However, not only may energy conversion processes be the best or the most efficient use for any kind of biomasses, but added-value processes may also be a potential option. In this sense, decision support methods become important to unlock the unrevealed potential of bioenergy as stated by the European Green Deal initiative of the European Commission [46]. In this paper, the properties of the obtained biochar produced from agro-forest feedstock were analyzed, aiming to select the best potential application--b biofuel, catalyst, for CO\({}_{2}\) sequestration and soil amendment or supercapacitor development--since those are known to be potentially efficient applications [47; 48; 49; 50]. Decision analysis has been used in order to assess the best application according to the properties of the obtained biochar. The use of a multi-criteria decision approach demonstrates its strength in the selection of the most efficient biomass/biochar along with the conversion routes of biorefinery value chains, considering the detailed proprieties of biomass and a life cycle impact perspective [51]. Decision methods were also focused on finding the best option to produce electricity, considering the pathway life cycle emissions and energy efficiency [52]. In another investigation on energy conversion, with an accent on biofuel, decision techniques [53] were applied to analyze the technology maturity, conversion efficiency, costs, emissions, and land requirement. However, none of the mentioned studies considered the biomass properties, biomass carbonization, and different product characterization as well as obtaining their application perspective based on a multi-criteria decision approach.