The furniture industry produces a large amount of wood waste every year, without proper
disposal. Due to the great abundance and the impact generated by the inadequate disposal of
these residues, this study aimed to give an adequate destination to wood residues through the
extraction of lactic acid for subsequent conversion into biopolymer. Residues from
muiracatiara (Astronium lecointei) and cedar (Cedrela odorata) species were used, comparing
them in terms of their chemical characterization and conversion into lactic acid, identifying
the best source for transformation into biopolymers. In lignocellulosic biomass are found the
major components: cellulose, hemicellulose and lignin, with cellulose and hemicellulose
being the target of this study. The residue of these species was mechanically processed by
shear and later submitted to chemical pulping and acid hydrolysis processes to transform its
lignocellulosic biomass to the glucose fraction. This glucose then underwent lactic
fermentation via Lactobacillus casei and Saccharomyces cerevisiae in order to produce lactic
acid. Lactic acid formation was evaluated for 3 periods, 24, 48 and 72 hours. This chemical
compound then underwent the polymerization process by direct polycondensation (PD),
through the addition of sulfuric acid to produce the biopolymers. The obtained crystals were
subjected to infrared and XRD analyses. Through this study, amorphous biopolymers were
obtained, but with good quality characteristics for hydroxyapatite. Regarding the lactic acid
yield, it showed similar amounts for the 24 and 48 hours times, with better peaks at 48 hours,
and a lower yield at the 72 hours, as for the lactic acid obtained from S. cerevisae and from L.
casei; there was no significant difference between the different species studied. For
commercialization, the polymers still need to go through purification and refinement
processes with a view to their application in orthotics, such as dental grafts.
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