The Synthesis And Study Of The Red Mud Settling Properties Of Hydroxamic Acids Flocculants Containing Methyl And Phenyl

In recent years, hydroxamic acid polymer flocculant has been widely used in red mud settlement rather than polymeric flocculant, because of its excellent effect caused widespread concern in the community. Hydroxamic acid can produce complexing effect with iron, copper and other ions in the red mud slurry, which has contributed to speed up the red mud sedimentation and clear up the supernatant fluid. However, the flocculant from home and abroad has a low settling rate, then improving its structure and enhancing its settling speed have became research focus in this paper. This paper introduced the strong hydrophobic aromatic group to the hydroxamic acid polymer structure and synthesized three kind of hydroxamic acid flocculant concluding hydrophobic aromatic group. The effects that the methyl styrene, methyl styrene and styrene have to the red mud settling performance were discussed.Firstly, polymerizate is synthesized by two synthetic routes, and the results showed aggregation is not easy to happen in the synthetic route 2 because of the effect of the hydroxamic acid. The acrylamide is used at the main monomer and the methyl styrene (OMS), of methyl styrene (PMS) and styrene (St) is used at the functional monomer in the synthetic route 1. The copolymerization happens under the appropriate temperature and oxidation-reduction initiator system, then the P (AM-OMS) of hydroxamic acid type polymer (M1), P (AM-PMS) of hydroxamic acid type polymer (M2) and P (AM-St) of hydroxamic acid type polymer (M3) with different hydrophobic properties were obtained by modified reaction under the alkaline solution with hydroxylamine hydrochloride. The total monomer concentration and ratio, reaction temperature, initiator concentration, stirring speed, reaction time, the influence of the masking agent on the polymerization reaction have been researched, and the synthesis condition has been optimized.Secondly, the products were characterized by using FT-IR, UV and color reaction of Fe3+, and its heat resistance was determined by TG.Finally, the red mud settling performance of hydroxamic acid flocculant with methyl phenyl has been researched though stuying the effects of relative molecular weight, the content of hydrophobic monomer and usage of the three flocculants on the settling properties of red mud of China’s alumina plant in Henan branch. The hydroxamic acid flocculant containing o-methyl phenyl, p-methyl phenyl and phenyl has been studied on the settling properties such as setting velocity, compressed degree of liquid-solid ratio and the clarification of clear liquid. The results which stuying on using three different molecular weight flocculants in red mud setting test show that M2 flocculant is better than HEDP-1800 used in plants on the sedimentation, and M1 is better than others on the clarification of clear liquid, it also has broad prospect of application and good market value.