Lignocellulose processing: a current challenge

Abstract

Lignocellulosic biomass, of which inedible crops are a renewable source, is expected to become one of the key renewable energy resources in the near future, to deal with global warming and the depletion of conventional fossil fuel resources. It also holds the key to supplying society's basic needs for the sustainable production of chemicals and fuels without impacting the human food supply. Despite this, the production of 2 nd generation biofuels and chemicals has not yet been commercialized. Therefore, the challenges involved in the production of lignocellulosic biomass derived fuels and chemicals must be addressed. The search for economic pretreatment methods has been recognized as one of the main hurdles for the processing of biomass to biofuels and chemicals. The conversion of all biomass components, lignin in particular, would greatly contribute to the economic viability of biomass based processes for 2 nd generation biofuels and chemicals. The highly organized crystalline structure of cellulose presents an obstacle to its hydrolysis. Hydrolysis of lignocellulose carbohydrates into fermentable sugars requires a number of different biomass degrading enzymes such as cellulases and hemicellulases. Still, a number of technical and scientific issues within pretreatment and hydrolysis remain to be solved. Depending on the raw material and pretreatment technology, the enzyme mixtures must be designed to degrade biomass carbohydrates. Rapid advances in enzyme, microbial and plant engineering would provide the necessary breakthroughs for the successful commercialization of biomass derived fuels and chemicals.

Valorization of Olive-Oil Industry Solid Waste: Statistical Optimization of Alkaline Extraction Conditions for Light-Coloured Hemicelluloses

“…Different extraction techniques have been performed and generally heat treatment is combined with alkali, acid or hydrogen peroxide (13). Biomass pretreatment is the most expensive step in bioprocesses representing about 20% of the total cost which limits the conversion of biomass into products (14,15). Therefore, optimization of pretreatment methods has a great economical importance in terms of industrial applications.…”

Can Microbially Derived Advanced Biofuels Ever Compete with Conventional Bioethanol? A Critical Review

“…Cheap sources of sugar are therefore a pre-requisite for the economic viability of any process (Singhvi et al 2014).…”

“…Sustainable production of different biofuel equivalents on a large scale invariably requires abundantly available and inexpensive lignocellulosic feedstocks, which have the added benefit that they do not compromise food security (Singhvi et al 2014). However, there are numerous technical challenges for obtaining commercially-relevant quantities of biomass and in achieving sufficient conversion efficiencies for lignocellulosic biomass to advanced biofuels (Galbe and Zacchi 2012;Huffer et al 2012;Singhvi et al 2014).…”

“…However, there are numerous technical challenges for obtaining commercially-relevant quantities of biomass and in achieving sufficient conversion efficiencies for lignocellulosic biomass to advanced biofuels (Galbe and Zacchi 2012;Huffer et al 2012;Singhvi et al 2014).…”

“…Much has been written on cellulosic biomass and its enormous potential for being a second generation feedstock (Perlack et al 2005). Beyond its wide-scale availability, it is the only alternate carbon source to fossil fuels that does not compromise food security (Singhvi et al 2014). Nonetheless, there are numerous challenges that must be addressed before advanced biofuels can be produced from lignocellulosic biomass.…”