Synthesis And Application Of Aqueous Two-phase AM-DMC-DMAA Co-polymer Flocculation

Polyacrylamide industry is developed in the1950s, the United States in1952with ammonia company first has carried on the research of polyacrylamideindustrial production, after two years into mass production. After the1962,several research in our country(such as jilin institute of chemical industrycompany)developed by polyacrylamide have been put into production, theproduct mainly is the cationic polyacrylamide, polyacrylamide imide group andnonionic polyacrylamide. Hot spots of research and development mainlyconcentrated in the synthesis of high molecular weight polyacrylamide.Polyacrylamide is a kind of important water-soluble polymer, its good watersolubility, adjustable, ionic type and molecular weight, are widely used in theflocculation, thickening, drag reduction, gel, bonding, scale, and other fields,polyacrylamide with homogeneous aqueous solution polymerization method, itsadvantages are simple technology, but as the reaction progresses, a dramaticincrease in viscosity of polymerization make to the system can’t to flow, lead to adifficult mixing, heat of reaction is difficult to eliminate, inverse suspension,inverse emulsion and precipitation polymerization to some extent, can alleviatethe viscosity of polymerization system problems, but is restricted by need to usea large number of organic solvents. Aqueous solution polymerization overcomesthe polyacrylamide in traditional polymerization reaction system in the processof the viscosity, heat of reaction is difficult to pass, the product is more difficultto dissolve the problems, with the pollution to the environment is small, fastdissolved, the viscosity of the reaction system reduce the advantages of itsproducts as well as the preparation technology has important significance to theresearch, we carried out a certain amount of research.Polymer aqueous system is composed of two incompatible polymer aqueoussolution, its application in bioactive substances and protein separation has beennearly half a century, French scholars will polyethylene oxide, poly2-vinyl pyridine chloride and ethylene oxide-2-vinyl pyridine chloride copolymer thisthree kinds of water activity, polymer solution mixed get a stable, low viscosityof dispersion system.Draw lessons from these thoughts, dissolve a water-soluble monomer inanother kind of water-soluble polymer in aqueous solution, this experiment inconventional joined another monomer in the reaction system of N, N-dimethylacrylamide (DMAA), and joined the inorganic salt, so that the synthesized morestable, flocculation effect more good product.Cationic high polymer flocculants of water-soluble polymer is a kind oflinear polymer, in people’s life and industrial sewage treatment and other aspectshave been widely used. Now our manufacturer of polyacrylamide (PAM) mostpart of the production of anionic polyacrylamide powder, while the number ofproduction of cationic polyacrylamide is very few, and most of the production isunder100t/a. For many years, our country’s domestic of PAM on the quality,quantity and variety are far cannot satisfy the production of our domestic needs.So imports about forty thousand tons. At present, in the United States, theemulsion polymer flocculant on the market demand has reached about75%, inJapan, the market demand of polymer emulsion type flocculant has accounted forabout10%. Visible, emulsion polymer flocculant of significant performanceadvantages, such as have been recognized. So we can predict future emulsionpolymer demand will come more and more each year. Cationic flocculant cannot only by charge neutralization can make pellet flocculation alternately, andcan be controlled by chains of polymer in the electrostatic force and hydrogenbond and van der Waals forces through active groups and colloidal particlesunder the action of the subtle between suspension bridge adsorption process, soas to make the colloidal particles flocculate, but also can be reflected and thenegatively charged solutes, generate insoluble salt. Cationic flocculant forinorganic and organic matter has very good flocculation and the effect ofpurification, and use the pH range is wide, toxicity is small, dosage is very few,these are the characteristics of the flocculants research and development. Thisexperiment, we will study the preparation of cationic polyacrylamide flocculantof method, and discussed under the influence of various factors, the flocculationperformance of the change and intrinsic viscosity. Using aqueous two-phase polymerization, with acrylamide (AM)、N,N-dimethylacrylamide(DMAA) and methyl acryloyl trimethylammoniumchloride (DMC) as comonomer, REDOX initiator preparation the molecularweight, stable performance of cationic polyacrylamide (CPAM) monomeremulsion. The initiator quantity added to, monomer ratio and concentration,reaction temperature, reaction time, dispersing agent, inorganic salt dosage onthe influences of characteristic viscosity of polymer product，according to thesynthetic product performance test and structure characterization, and studied itsoil sludge flocculation effect.(1) The results show that the optimization of synthesis condition is: totalmonomer concentration33%, AM、 DMC and DMAA quality ratio for2~4:0.8~1.2:0.15~0.25, REDOX dose for monomer0.2%~0.5%(antioxidant:reducing agent=1), dispersing agent and total monomer quality ratio is0.8,inorganic salt accounts for monomer0.5%~2%, the temperature is45℃, reaction4~6h. Results show that the product of the synthesis of oil sludge also has thevery good flocculation effect.(2) By FTIR and UV spectrophotometer, ubbelohde viscometer, such as todetermine the structure of synthetic polymer in AM, DMAA and DMC structureunit; Through to the monomer conversion rate is calculated, the experimentmeasured the monomer conversion was94.9%; Through to the polymer intrinsicviscosity test, the experiment measured the relative molecular mass of copolymerabout463million; Based on the determination of cationic degree, the experimentmeasured the degree of cation polymer tendency for3.5mmol/g; By usingultraviolet spectrophotometer, experiments show that the polymerizationproducts in a certain concentration, the flocculation effect is good.(3) Through the addition of inorganic salt in the polymerization processtype and dosage of the effect on the stability of the polymerization productstesting, the results show that we need to further improve the salt resistance ofpolymers.(4) Based on the viscoelastic polymerization products line test, preparationof the experiment show that the product has good viscoelasticity.(5) Through to the oilfield sludge flocculation experiment, the results showthat the ratio of AM and DMC with DMAA quality for2~4:0.8~1.2:0.15~0.25, the oxidation of reducing agent content is0.2%~0.5%of monomer(oxidant/reductant=1), the total mass of the dispersant and monomer ratio0.8,inorganic salt accounts for0.5%~2%of monomers, temperature of45℃,4~6hreaction, synthesis of the product of the oilfield sludge has good flocculationeffect.(6) Through to the papermaking sludge flocculation experiment, the resultsshow that the temperature of45℃, the reaction time is4~6h, ratio of AM andDMC with DMAA quality for2~4:0.8~1.2:0.15~0.25product of papermakingwastewater treatment has the best concentration.