The IR spectrum for the sugar cane ash (Fig. 3) presents less
number of peaks with respect to the other wastes, in particular, gave
further evidence of the content of quartz (SiO2) in the residue. The
peaks located around 1000 and 800 cm1 (symmetric stretching of
SiAOASi) and the band in the range 770 cm1 (asymmetric stretching
of SiAOASi), typical of silicate network (McMillan, 1984;
Barbieri et al., 2003) confirms the presence of quartz in the ash.