Study of thermal behavior of deoiled karanja seed cake biomass: thermogravimetric analysis and pyrolysis kinetics

Karanja is a medium sized evergreen tree which has minor economic importance in India. The nonedible seed kernel contains 27-30% oil that is used for biodiesel production, leaving the remaining nonedible seed cake as a waste product. The aim of the present work was to obtain kinetic parameters in relation to technological parameters in nonedible seed cake biomass pyrolysis conversion process to bio-oil and biochar. Effects of heating rate on karanja seed cake slow pyrolysis behavior and kinetic parameters were investigated at heating rates of 5, 10, and 20°C/min using thermogravimetric analysis (TGA). Thermogravimetric experiments showed the onset and offset temperatures of the devolatilization step shifted toward the high-temperature range, and the activation energy values increased with increasing heating rate. In the present study, isoconversional method was applied for the pyrolysis of karanja seed cake biomass by TGA and the activation energies (118-124 kJ/mol) and the pre-exponential factors obtained using progressive conversion. Proximate-ultimate analyses, energy value, surface structure, and Fourier transform infrared spectra of the biomass processed under conditions were reported. The pyrolysis resulted in upgradation of the energy value of seed cake biomass from 18.1 to 24.5 MJ/kg; importantly with high carbon and low oxygen contents. The approach represents a novel method for the upgrading of karanja seed cake that has significant commercial potential

A Review on 1st and 2nd Generation Bioethanol Production-Recent Progress

Today's society is based on the use of fossil resources for transportation fuels. The result of unlimited consumption of fossil fuels is a severe depletion of the natural reserves and damage to the environment. Depleting fossil reserves and increasing demand for energy together with environmental concerns have motivated researchers towards the development of alternative fuels which are eco-friendly, renewable and economical. Bioethanol is one such dominant global renewable transport biofuel which can readily substitute fossil fuels. Conventionally, bioethanol has been produced from sucrose and starch rich feedstocks (edible agricultural crops and products) known as 1st generation bioethanol; however this substrate conflicts with food and feed production. As an alternative to 1st generation bioethanol, currently there is much focus on advancing a cellulosic bioethanol concept that utilizes lignocellulosic residues from agricultural crops and residues (such as bagasse, straw, stover, stems, leaves and deoiled seed residues). Efficient conversion of lignocellulosic biomass into bioethanol remains an area of active research in terms of pretreatment of the biomass to fractionate its constituents (cellulose, hemicellulose and lignin), breakdown of cellulose and hemicellulose into hexose and pentose sugars and co-fermentation of the sugars to ethanol. The present review discusses research progress in bioethanol production from sucrose, starch and cellulosic feedstocks. Development of efficient technology to convert lignocellulosic biomass into fermentable sugars and optimization of enzymatic hydrolysis using on-site/ in-house enzyme preparation are the key areas of development in lignocellulosic bioethanol production. Moreover, finding efficient fermenting microorganisms which can utilize pentose and hexose sugars in their metabolism to produce ethanol together with minimum foam and glycerol formation is also an important parameter in fermentation. Research has been focus