After delignification, pulp was filtered and washed with distilled
water until neutral pH was reached. Bleaching was realized in two
stages; the first consisted in plunging NaOH treated fibers in 0.2M
NaClO2 solution with 1:30 w/v ratio at 75 ◦C for 2 h, and the second
consisted in submerging the fibers in a 3MH2O2 solution with
1:10 ratio and pH 11 using magnesium sulfate (0.2 wt%) to protect
the fibers and pentetic acid (0.5 wt%) as chelant.