A novel surfactant assisted transition metal pretreatment of chili post harvest residue for the production of bioethanol

Increase in consumption as well as depletion of fossil fuels and environmental concerns about the consequences of burning fossil fuels leads to search for alternative renewable fuels. Lignocellulosic biomasses are plenteous in nature and are rich in celluloses which can be converted to fermentable sugars for the production of bioethanol. Lignocellulosic biomass is composed of cellulose, hemicelluloses and lignin. Many physio-chemical, structural and compositional factors hinder the enzymatic digestibility of cellulose present in the lignocellulosic biomass. Pretreatment is to be carried out to make cellulose accessible for enzymatic saccharification by the removal of hemicelluloses and lignin. A common pretreatment strategy cannot be used for all feed stock since there is large variation in composition even between samples of same biomass from different sources. Chili post harvest residue is an underexploited lignocellulosic biomass and India has over a surplus availability of 0.5 million tons of this residue. Conversion of this feedstock to ethanol requires pretreatment to make it more accessible for the enzymes used in saccharification. Though several pretreatment regimens have been developed for addressing biomass recalcitrance, only very few seem to be promising as an industrial process. The aim of the study was to develop a novel surfactant- assisted transition metal pretreatment strategy to exploit the surplus available biomass in India- the chili post harvest residue for the production of bioethanol as well as to optimize various process parameters affecting pretreatment and hydrolysis.