Study On The Synthesis Of DADMAC-co-AM And Their Flocculation To White Water In Paper Making

With the development of paper making industry, being short of resource, the pressure of environmental protection, comprehensive treatment of white water is getting more and more attention in the world. Recycle of useful suspended solids such as cellulose and loadings and so on is significant in reducing production cost and improving white water reuse rate and environmental protection. DADMAC-AM copolymers were synthesized and their flocculation in white water treatment of paper making were studied in this work. The article first discussed the synthesis theory, the purification of monomers, synthesis way, constitution control, the affection of initiator concentration and ratio of monomers to the synthesis of copolymer. Then their flocculation effects in three simulated waster waters are reviewed. We studied the relation of molecular weights with flocculation effects and how cationicity affects their flocculation. The results showed that the copolymers exhibited significant flocculation effect in the treatment of the water containing kaolin and fine. Small amounts of addition of the copolymer can reduce decoloration and deturbidity greatly. Among them the copolymer with molecular weight of two million works best. The largest percentages of decoloration and deturbidity were as high as 96.6% and 98.2%, respectively. The retention of the fine and kaolin was 96.8% and 72.6%, respectively. The higher is the cationicity, the lower optimum addition dosage of the copolymer and better flocculation effects can be viewed.