Synthesis Of Sodium Oleate Polymeric Surfactants And Its Application On Wasterpaper Deinking

Using waste paper to make pulp and paper has been aroused the widespread attention around the world,because it has many advantages in low relative cost,saving raw fiber resources,simplifying the process of papermaking,reducing environmental pollution and concribute to environmental protention,Waste paper deinking agent is the most important chemical assistant in the process.At present,there are few varieties of domestic deinking agents,the most of deinking agent are compound with low molecular surfactants or imports,however,this deinking agents has some defects.for example,to much foam in the process of waster paper deinking,ink performance capture is bad,ink deposition resistance founction is poor,paper whiteness is low in the deinking and so on,so it can not meet the requirements of commercially available small molecule surfactants.Therefor,to research and development the efficient new type deinking agent is one of the key work to improve the level of waste paper deinking.In this paper,The tow novel type NaOL-AA and NaOL-AA-SMAS surfactant with high molecular copolymer were synthesized by aqueous solution polymerization method.sodium oleate(NaOL)is the main raw material.The reaction conditions and the performance of deinking agent were studied.The main contents and results of the study are summarized as follows:(1)Anionic copolymer of anionic surfactant NaOL-AA was synthesized with aqueous solution free radical polymerization using sodium oleate(NaOL)and acrylic acid(AA)as starting materials.Compared with the the deinking effect of the prepared products by the flotion deinking with waste joural paper,and evalued the effect by whiteness and the residual ink concentration,the optimum proportion and reaction conditions were investigated.Afterwards,the comparison of dinking efficiency between the self-prapared and the mixed deinking agents was carried out.The surface residual ink and degree of crosslinking of regenerated fiber were characterized by scaning electronmicroscope(SEM).Then,The chemical structure of the products were characterized by FT-IR,and the surface physical properties were determined.The results showed that the optimal conditions for the synthesis process are as follows: n(NaOL)∶n(AA)=1∶3;reaction temperature 85℃;reaction time 6h;dosage of initiating agent w(ammonium persulfate,APS),2% of the mass of total reactants;and polymer pH=8-9.the whiteness of the deinked waste paper could achieve 67.6% and the residual ink on the waste paper drops to 53.0mm2·m-2.When the blended product at the mole ratio of m(NaOL-AA)∶m(FMEE)=1∶2,the whiteness of the deinked pulp increased by 2.2% ISO.The SEM photos showed that the surface of fiber was smoother and the effective residual ink concentration was lower.GPC showed that the mean molecular weight Mn was 3380 and the polydispersit Mw/Mn was 1.26.Physical performance test results showed that the surface tension of synthetic product was25.35mN·m-1,the CMC value was 0.164g·L-1,the bubbly stability was 82.1%,and separation water time method measured emulsifying power was 452 s.(2)Anionic copolymer of anionic surfactant NaOL-AA-SMAS was synthesized with aqueous solution free radical polymerization using sodium oleate(NaOL),acrylic acid(AA)and sodium allylsulfonate(SMAS)as starting materials.Compared with the the deinking effect of the prepared products by the flotion deinking with waste joural paper,and evalued the effect by whiteness and the residual ink concentration,the optimum proportion and reaction conditions were investigated.Afterwards,the comparison of dinking efficiency between the self-prapared and the mixed deinking agents was carried out.The surface residual ink and degree of crosslinking of regenerated fiber were characterized by scaning electron microscope(SEM).Then,The chemical structure of the products were characterized by FT-IR,and the surface physical properties were determined.The results proved that the optimal synthesis process is as follows: n(NaOL)∶n(SMAS)∶ n(AA)=1 ∶ 1 ∶ 3,reaction temperature 85 ℃,reaction time 5h,w(APS)=2.5%(the mass of reactants),which has the optimal deinking effect.When the mixed deinking agent of m(NaOL-AA-SMAS)∶m(AEO-9)=2∶1,the brightness of the deinked waste paper could reach to 71.9% and the residual ink concentration is only 42.3 mm2·m-2.The SEM photos showed that the surface of fiber was smoother and the effective residual ink concentration was lower.GPCshowed that the mean molecular weight Mn was 7180 and the polydispersit Mw/Mn was 1.02.Physical performance test results showed that the surface tension of synthetic product was 24.32mN·m-1,the CMC value was0.149g·L-1,the bubbly stability was 90.2%,and separation water time method measured emulsifying power was 513 s.(3)The experiment was build on the NaOL-AA as deinking agent,and evalued the effect by whiteness and the residual ink concentration,the method of using flotion deinking on journal paper.reseached the different temperature and time,different deinking method to influence of deinking effect,optimization of process conditions.The reasult showed that the surfactant dosage of NaOL-AA was 0.2%,NaOH was 1%,Na2SiO3 was 3%,the pulping temperature was 60℃ at 30 min,the curing temperature was 55℃ at 30 min,the floation temperature was 45℃ at8 min.under this condition,the whiteness could be up to 68.7%ISO,which improved 1.1%ISO than unoptimized.