Study on the retention mechanisms of high molecular weight cationic polyacrylamide

Colloid titration and Zeta potential analysis were applied to measure the charge arid Zeta potential of paper furnish under the conditions of only adding CPAM and adding both CPAM and polyaluminum chloride (PAC). The results show that if only CPAM is added, the Zeta potential of the furnish changes little but CTR changes obviously. If the CPAM is added after the PAC, the dissolved charge of the furnish changes little while the Zeta potential changes more. That illustrates that the function of PAC and CPAM in the furnish system is different. PAC could eliminate the anionic trash but could not significantly increase the Zeta potential, which benefits the bridging flocculation of CPAM and reduces the consumption of CPAM.