Metal ions presenting in deinked pul p not only catalyze the decompositio n of sodium dithionite,but also induce color re version of pulp,thus bring down whiteness of pulp.

• 脱墨浆中的金属离子不仅催化分解连二亚硫酸钠(保险粉),而且导致纸浆返黄,降低纸浆白度。