Front Matter

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212 Introduction to Renewable Biomaterials

(starch crops), could prove to be an ideally inexpensive and abundantly available source
of sugar for fermentation into transportation fuels. Cellulose crystallinity, accessible
surface area, protection by lignin, and sheathing by hemicelluloses all contribute to
the resistance of cellulose in biomass to hydrolysis. The biomass pretreatment and the
intrinsic structure of the biomass itself are primarily responsible for its subsequent
hydrolysis. The conditions employed in the chosen pretreatment method will affect
various substrate characteristics, which, in turn, govern the subsequent fermentation
of the released sugars. Therefore, pretreatment of biomass is an extremely important
step in the synthesis of biofuels from lignocellulosic biomass, and there is a critical
need to understand the fundamentals of various processes, which can help in making a
suitable choice depending on the structure of the biomass substrate and the hydrolysis
agent. A vast array of materials are suitable for the production of biofuels. It must
be emphasized that it is not always possible to transfer the results of pretreatment
from one type of material to another. Furthermore, one technology that is efficient for
a particular type of biomass material might not work for another material. Various
pretreatment processes for lignocellulosic biomass have their specific advantages and
disadvantages. The choice of the pretreatment technology used for a particular biomass
depends on its composition and the by-products produced as a result of pretreatment.
These factors significantly affect the costs associated with a pretreatment method.

References


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