Effect of cationic polymer on deinking efficiency of Mixed Office Waste

Some cationic polymers as flocculants to optimize the deinking process of Mixed Office Waste (MOW) were studied in this paper. The results showed that with the adding of condign dosage of CPAM (0.05%), the brightness of the deinked pulp could be increased 5.2 units and the residual ink particle content of the deinked pulp was reduced by 66.77%; with dosage of PAC (0.8%), the brightness could be increased by 4.5 units and the residual ink particle content was reduced by 65.41%; with dosage of CS (1.0%), the brightness could be increased by 4.2 units and the residual ink particle content was reduced by 64.65% under the following deinking conditions: dosage of deinking additive 0.5%, NaOH 2.0%, Na2SiO3 2.0%, EDTA 1.5%, H2O2 1.0%, pretreatment temperature 80 degrees C and time 50 min. Among three cationic polymers, the order of influence on the deinking result was CPAM>PAC>CS. The experiment also indicated that there was a good functional correlation between the quality indexes of the deinked pulp and the main colloidal characteristic parameters. When the zeta potential, transmissivity increased and contact angle, absorbance of deinking system decreased, the deinked pulp quality would become better.