Ultimate Analysis

For ultimate analysis, the total carbon and hydrogen in agro-wastes usually vary from 40–50% (*w*/*w*) and 4–6% (*w*/*w*). Overall, this analysis involves determining total carbon, hydrogen, nitrogen, and sulphur content in the agro-waste sample. The total oxygen can be calculated by subtracting the total amount of nitrogen, hydrogen, carbon, and sulphur from the known weight of the sample. Hence, this analysis can be carried out using a CHNS analyzer on a dry basis.

Similarly, compositional analysis can be performed using the "Van Soest" method, classified as the National renewable energy or Technical Association of pulp and paper industry method. Most agro-wastes are composed of cellulose, hemicellulose, and lignin; albeit, with a varying degree of composition in different waste samples. The degradation temperature of cellulose is around 240–360 ◦C, leading to the production of liquid products after conversion. Hemicellulose, which surrounds the cellulose, comprises a short and heterogeneous branched chain of polymers. It also links cellulose with lignin. Lignin is the most complex and aromatic compound of higher molecular weight polymer with the crosslink made up of phenolic groups [16]. Other inorganic elements present in the biomass include Na, K, Mg, Cl, etc., and some components such as proteins, resins, gums, etc.
