Study On The Preparation And Application Of Chitosan Derivatives Magnetic Beads

With the rapid development of economy, industrial wastewater and domestic sewage dumped into the sea rising, many breeding waters polluted by heavy metals and other compounds, have seriously affected the ecological environmen of coastal waters, causing many contaminants increasing of oyster, seriously affected the oyster production and edible quality, marine shellfish living body of petroleum hydrocarbons, mercury and cadmium residues in the total level of the rise, which the rise of cadmium is significantly. At present, shellfish purification technology has been established in domestic and foreign, through purification, the sediment could be removed, the pathogenic microorganisms content could be reduced, but the removal of heavy metals in the Oyster no effective removal method. Chitosan has strong heavy metal chelation, but its solubility is limited to applications, the paper prepared chitosan derivatives with strong metal chelation and solubility, its use to the process of farming oyster, research cadmium change in oyster. Preparation of chitosan and its derivatives magnetic ball which more easily separation medium, study the adsorption kinetics and adsorption thermodynamics of heavy metal Cd2+, which be applied to the study of removing heavy metals in oyster highly polluted by heavy metals Cd. The following conclusions of this paper can be:(1) The best conditions of preparation of 2-3mm diameter magnetic ball were:3% concentration of chitosan or derivatives; Chitosan or derivatives Fe3O4 magnetic particles with mass ratio 1:1; cross-linking agent glutaraldehyde solution using 1.25%.(2) Analys the magnetic ball, the water content as high as 94.13%, the content of Fe3O4 was 48.87%. The amino content of chitosan is 5.83mmol/g; the carboxyl content of N, O-carboxymethyl chitosan is 4.65mmol/g, amino content of is 3.32 mmol/g; the functional groups content of N, O-carboxymethyl chitosan is highest. In the magnetic beads, the functional groups content of N, O-carboxymethyl chitosan magnetic ball is highest. Using infrared spectroscopy, X-ray diffraction and electron microscope scanner characterize the various substances. (3) Study the magnetic balls adsorption kinetics and adsorption thermodynamics of the Cd2+, found magnetic beads on the adsorption of Cd2+according with Lagergren equation adsorption model 2 and the Langmuir adsorption equation.(4) Established oyster contamination model. Oxygenating, putting bait and putting 0.05g/L of chitosan derivatives in the breeding process have a great role on the promotion of oyster cadmium discharges for the light pollution oyster. For heavy pollution oysters, the magnetic beads prepared in this study was used by removing cadmium from the body. The study found that pH value of oyster meat slurry is an important factor, carboxyl methyl-chitosan magnetic beads are the best adsorbent of heavy metal cadmium. There would be good removal effect of cadmium on oyster meat using carboxymethyl chitosan magnetic beads without adjustting pH value, it can be achieved removal rate reached 90%.Heavy metal Cd accumulation and exclusion in the oyster was stuied in this paper. It is very important for the development of appropriate management measures,to carry out monitoring sanitary quality of farmed oysters and the health farming technology of oyster, promoting the development of our shellfish purification technology, to reduce the heavy metals content in oyster flesh, which oyster products reaching the development, production of functional requirements, there by promoting the development and utilization of oyster, speed up the process of China's marine resources development.