Effect of organosolv and soda pulping processes on the metals content of non-woody pulps

In this work the effect of different pulping processes (ethyleneglycol, diethyleneglycol, ethanolamine and soda) of tow abounded raw materials (empty fruit bunches – EFB and rice straw) on the ash, silicates and metals (Fe, Zn, Cu, Pb, Mn, Ni and Cd) content of the obtained pulps have been studied. Results showed that pulps obtained by diethyleneglycol pulping process presented lower metals content (756 μg/g and 501 μg/g for EFB and rice straw pulp, respectively) than soda pulps (984 μg/g and 889 μg/g). Ethanolamine pulps presented values of holocellulose (74% and 77% for EFB and rice straw pulp, respectively), α-cellulose (74% and 69%), kappa number (18.7 and 18.5) and viscosity (612 and 906 ml/g) similar to those of soda pulp, and lower lignin contents (11% and 12%).