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Bio-energy from lignocellulosic biomass is cleaner, sustainable, and one of the renewable energy sources that could help meet some of our energy demand. Unlike fossil fuels, it can be grown and used repeatedly and its use can replace the fossil fuels. In addition to this, these materials are easily available either in the form of agricultural waste or forest residues and are economically viable. The current study focuses on physico-chemical characterisation of three commonly available lignocellulosic biomasses of north-east India such as Castor (Ricinus communis), Jatropha (Jatropha curcas), and Miscanthus (Miscanthus sinensis) for second generation biofuels production. Ultimate analysis (CHNSO), thermogravimetric analysis, X-ray diffraction, Fourier transformation infrared (FTIR), and oxygen bomb calorimeter techniques were used to characterise the above mentioned three lignocellulose biomasses. It was found that the cellulose content of three biomasses varied from 40% to 44%, hemicellulose content from 8% to 14%, and lignin content varied from 21% to 30%. Chemical structure of lignocellulose is studied through FTIR. The crystallinity index of Castor and Jatropha is similar, i.e., ~69%, where as crystallinity index of Miscanthus was 72%. Due to the presence of higher carbon and cellulose content along with less moisture (10%-12%), ash (5%-10%), sulphur (0.1%-0.8%), and extractives (12%-20%) make them a very good source for production of alcoholic fuels through a biochemical route. [ABSTRACT FROM AUTHOR]

Thermogravimetric analysis of three lignocellulosic biomass such as Miscanthus grass, Castor stem, and Jatropha stem under high purity nitrogen atmosphere were carried out over a temperature range of 25 °C-900 °C at three different heating rates of 10, 15, 20 °C min-1. The profiles generated from thermal decomposition process signified that except dehydration there were three main stages of degradation occurred associated with three main components (hemicellulose, cellulose, lignin). The temperature peaks at maximum weight loss rate obtained from Differential thermogravimetric thermograms changed with increasing heating rate. The activation energy and pre-exponential factor were calculated by applying two model-free methods and compared. The kinetic parameters obtained from Kissinger and Ozawa methods were in good agreement with the experimental results. The value of kinetic parameters explained the thermal stability of the biomass. The thermal analysis could not infer the composition and chemical structure of lignocellulosic biomass; hence FTIR spectroscopic analysis has been carried out. [ABSTRACT FROM AUTHOR]

This work reports the kinetics and pyrolysis characteristics of three waste biomass, viz., pinewood sawdust, sal wood sawdust, and Areca Nut husk powders. Pyrolysis was conducted with five different heating rates of 5 °C min−1–25 °C min−1 under an inert atmosphere. The burnout temperatures and physicochemical properties of the three biomass were reported in this work. The results indicated that heating rates widely affected the burnout temperatures during combustion. When heating rates increased, the burnout temperatures shifted towards the higher temperature region. It was observed that kinetic parameters and degradation rates were functions of heating rate and temperature. However, activation energy varied with the change in heating rates. The activation energy, pre-exponential factor, and derivative of thermogravimetric analysis (TGA) (DTG) characteristics were affected by the rise in heating rates. At higher heating rates, DTG peaks shifted to the higher temperature region, but it does not affect the conversion of biomass. TGA and DTG analysis indicated that all the three biomass undergone three degradation stages, and differential scanning calorimetric analysis confirmed the endothermic and exothermic pathways of these biomass. Fourier transform infrared spectroscopy analysis revealed the presence of various functional groups in the biomass. [ABSTRACT FROM AUTHOR]

This work presents the thermochemical characterization of some nonconventional oil containing seeds. The non-edible and less-edible oil seeds such as Mahua (Madhuca indica), Karanja (Pongamia pinnata), Niger (Hyoscyamus L. Niger), and Linseed (Linum usitatissimum) were characterized on the basis of their degradation profile, oil percentage, cellulose, hemicelluloses, lignin, and mineral content. TGA analysis confirmed that the active pyrolytic zone for all the seeds lies in the temperature range between 150 and 450 °C. It was observed that these seeds contain maximum percent of oil/extractives such as Mahua: 57.16%, Karanja: 53.19%, Niger: 39.75%, and Linseed: 33.55%. The result indicated that these seeds contains higher amount of celluloses than that of hemicelluloses and lignin. The elemental analysis confirmed that these types of biomasses are suitable for pyrolysis due to the presence of less sulphur, less moisture, and higher volatile matter content. The suitability as a feed for fuel production was observed from the relation between O/C and H/C ratio from the Van Krevelen diagram. [ABSTRACT FROM AUTHOR]