The Synthesis And Application Of Polyacrylamide Flocculant Containing N-hydroxymethyl And Aromatic Hydrocarbon Group

Red mud settlement plays an important role in the process of alumina production.The efficiency of flocculants on settlement is particularly critical.In order to improve the settling rate of red mud,reduce the compressed liquid/solid ratio of underflow and improve the clarification performance of overflow,a suitable settling tank and an efficient flocculant should be selected.In this thesis,three kinds of polyacrylamide flocculants containing N-hydroxymethyl and aromatic hydrocarbon group were prepared and optimized,to find out a new flocculant with good performance on red mud settlement.In this thesis,three kinds of flocculants(P(AM-HAM-St),P(AM-HAM-PMS)and P(AM-HAM-AMS))were prepared by inverse emulsion polymerization.Acrylamide(AM)was selected as main monomer,and N-(hydroxymethyl)acrylamide(HAM)was selected as functional monomer.Styrene(St),p-methylstyrene(PMS)and a-menthylstyrenethe(AMS)were selected as hydrophobic monomer respectively.Deionized water was selected as solvent and paraffin liquid was selected as oil phase,NaHSO3-K2S2O8 was selected as initiator and the mix of Span-80 and Tween-80 was selected as emulsifier.The effects of concentration and ratio of monomer,temperature,concentration of initiator,stirring speed,time,HLB and oil ratio on polymerization were investigated.The main conditions were optimized by the use of orthogonal design.The structure of three products was characterized by IR,UV and TG.The results showed that all the structure of three products meet the requirements of experimental design.And the products showed good thermal stability respectively.The settling performance of the three products was investigated on the red mud fluid from Henan Branch of China Aluminum.The results showed that P(AM-HAM-PMS)is the best on the red mud settlement.A comparision of P(AM-HAM-PMS)with Nalco 9779 and H 0503 was made,which are used in factory currently.The results showed that P(AM-HAM-PMS)is better than Nalco 9779 and H 0503 on settling rate,compressed liquid/solid ratio and clarification performance of overflow.In all,P(AM-HAM-PMS)has broad application prospects.