| Polymer materials,which were loved by all walks of life as their excellent properties. Although polymer materials have brought convenient for human’s life,they brought serious environmental problems as the great expanded of their consumption. Generally speaking, polymer was a kind of stabitiy and degradation resistance organic. They could lead to poor biodegradability, affecting the survival of microorganisms in water, and bringing great difficulties for the governmance of pollutants either.lt was difficult to achieve an ideal removel effect through conventional microbial as the characteristic of hard degradation.Therefore it was of great significance for looking for a kind of green low carbon, high efficiency and energy saving technology for modern environmental protection industry.The thesis intended to utilize nano-knife materials with the assisted of high-speed mechanical stirring as the method to the experimental and theoretical studies of simulated wastewater containing polymers,such as Carboxymethyl cellulose (CMC),Gelation and Polyvinyl alcohol(PVA).Discussing the main factors for the physical decomposing on these polymers in detail. And the feasibility of nano-knife materials sheared decomposing polymer materials by some analysis methods has been investigated. The main contents are as follows:(1) Using high-speed mechanical force assisted nano knife materials shearing Carboxymethyl cellulose,and analysising its viscosity by changing the shearing time and the dosage of quartz sand. The results showed that the viscosity has been reducted within 5 min from 8.9 mPa.s to 3.6 mPa.s when the aqueous solution with CMC concentration of 1g/L,quartz sand mass 3 g, and the decomposing efficiency were 59.6%. High exclusion chromatography analyzing showed that the samples after shearing appear several smaller peaks compared with the original sample.The changes of molecular weight and molecular weight distribution mean that quartz sands sheared carboxymethyl cellulose into different molecular weight, and the concentration of these substances increased with the increasing of quartz sands and shearing time. FT-IR characterization of the CMC samples before and after shearing showed that the reason why viscosity,molecular weight and molecular weight distribution had changed, which were possible the breaking off of the glucoside bond (C1-O-C4).(2) Viscosity of Gelatin solution decreased with the increasing of quartz sands and shearing time.The solution viscosity were decreased from 11.2 mPa.s to 6.2 mPa.s and decomposing rate were 51.18% when Quartz sands were 15 g, shear time were 4 min.Quartz sands were 3.75 g, shearing time increased from 1 min to 16 min, viscosity of gelatin decreaseed from 11.2 mPa.s to 6.7 mPa.s,the decomposing rate were 47.24%. Changing the initial concentration of gelatin, the viscosity of the solution did not changed obviously.(3) The high-speed mechanical shearing assisted mode research found that the initial concentration was the key factor affecting them cut PVA chain, and low concentration showed better decomposing than that of high concentration.But these didn’t produce a obviously reduction in PVA concentration with the increasing of the shear time and the dosage of quartz sand,the highest degradation rate were only 24.95%. The ultrasound-assisted mode showed a lower effect than that of high-speed assisted, quartz sands which were dispersed into solution exhibited 10% of PVA removal rate.This technology has a potential prospect by utilizing nano-knife materials decomposing polymer pollutants.The treatment technology depended entirely on physical force,making it in green ang low costing.And it is of great significance to realize sustainable development. |
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