Page 35 - PR 2014 2016 03 Applications of Ionizing Radiations

Applications of Ionizing Radiations | Progress Report 77

Energy Production with high molecular weight (alpha) presented

a total reduction. It is important to point out
Radiation effect on structure and that the changes observed in the cellulose
composition of sugarcane bagasse suggest some effects on the lignin structure,
since the cellulose is protected by lignin and
The structural and chemical modifications hemicelluloses. The obtained results show
produced by ionizing radiation in the sugar- that radiation interacts initially on the sur-
cane bagasse are very important matter to face of hemicelluloses liberating the arabi-
be included in the second generation energy nose, and then acts on the xylose polymers.
production and it depends on the combination The main byproduct liberated is acetic acid
of pretreatment technologies to transform originated from the deacetylation of hemi-
these modifications into bioethanol pro- celluloses; the removal of this acetyl group
duction growth. The industrial application enhances the accessibility of the enzyme to
of electron beam accelerator on the second the cellulose and can increase the enzymatic
generation process is a challenging task and hydrolysis. This sequence of radiation inter-
very feasible since the equipment could take action probably happens due to the location
part in the first generation installation. The of xylose in the backbone of arabinoxylan,
radiation processing promotes an increase in while arabinose is located in the branches
the soluble portion that is related to hemicel- of the macromolecules where the glycosidic
lulose and cellulose cleavage, and cellulose bonds are easier to hydrolyze.

Ash Solubles Beta cellulose Alpha celulose Lignin Hemicellulose

100

80
Compositional Fraction (%) 60

40

20

0
Untreated 5 kGy 10 kGy 20 kGy 50 kGy 70 kGy 100 kGy 150 kGy

Figure 54. Compositional fraction of sugarcane bagasse untreated and irradiated in different absorbed doses.