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With the development of industrialization, a large number of heavy metals in a variety of ways to enter the water, the resulting heavy metal content in the water is increasing. Seaweed has metal enrichment, and therefore the seaweed larger security risks. The activity of trace metal elements, the organism toxicity and can be used more often than not depending on the total concentration thereof, but in its chemical forms exist, i.e. element active and its morphology closely related. Therefore, the determination of heavy metals in the presence of morphological significance. On the basis of previous studies, the paper mainly do the following aspects: 1. Kelp of Cd, Pb adsorption and Ca, Mg, Zn adsorption effect impact. Running of the Bulls, flat dish, mixed, the Rongfu four seaweed varieties as raw materials, study kelp heavy metal adsorption of heavy metals, Pb adsorption and metal Ca, Zn, Mg of add. Kelp on the difference in the amount of adsorption of each metal in the same metal ion concentration, which mixed species of Cd, Pb adsorption capacity is higher than the other three species. Within the measuring range, with the increase of the added amount of Cd, Pb, and the amount of the four seaweed on the adsorption of Cd, Pb also increased significantly. In seaweed metal adsorption experiments, the solution in the presence of various metal ions, different kelp adsorption capacity of the different metal, to co-exist, the mutual influence between. In seawater adding metal Cd, Pb and Ca, Zn, Mg, after the measurement of the three on the amount of adsorption of the target metal Cd, Pb, and its results are very different. The content of the added metal is different from the trend of changes in the amount of adsorption of the target metal is also different, and different varieties of seaweed, and the variation is not the same trend. 2. Seaweed adsorption kinetics of Cd, Pb. Seaweed and sargassum adsorption of Cd, Pb kinetic results indicate that macroalgae biosorption for fast adsorption process at the beginning of the end of the process in about 20min to 30min after adsorption slowly close to balance. Biosorption rate law is mainly determined by the physical and chemical nature of biosorption, etc. related to different chemicals with different biological surface structure and chemical composition and ions in solution state. Sargassum seaweed on metals Cd, Pb adsorption kinetics can use fake - two model fitting. Different algae and different treatment will affect the amount of adsorption and the adsorption rate of the algae and the adsorption capacity of the different metals, and the same kind of seaweed also different. Algae of different metal adsorption capacity of ion structure, that is related to the stability of the structure of the metal ions, the ability of chemical ligand complexing ability, competitiveness. In addition, the adsorption capacity of is also selective adsorption functional groups. Sargassum seaweed in the form of metal elements exist. Using different solvent extraction Sargassum, kelp, the lipophilic component, the water extraction component, an acid component is extracted, the alkali extract various components of the component and the slag 5, analysis of the different components of Ca, Mg, Zn, Cd and Pb content of five metal elements. The results showed that the five kinds of metal in the distribution of the respective components are completely different, within the limit of detection, the lipophilic component is not detected in five metal and the remaining portion containing different amounts of metal elements. The elements Ca: Ca content is higher than in the seaweed in the Sargasso content. Kelp in the Ca alkali and alcohol Shen, slag, retained fluid levels are very high, 65.08% of the total kelp Ca content of three parts; Sargasso three parts Ca addition, The acid component is extracted by alcohol precipitation alcohol liquid Ca content is slightly higher than the first three. Mg element: kelp Mg content is much lower than the Sargasso of Mg content. Mg kelp mainly present in the the reserved liquid components, accounting for 55.92%, the remaining components were relatively small. The Sargasso slag, alkali extraction and alcohol precipitation, dialysate, contain high Mg content of about 20% in the reserved liquid. Zn elements: Zn content below Sargasso Zn content in kelp. The Kelp Zn present in the water extract part, accounting for 51.3%. Sargasso of Zn, the reserved liquid content of the highest, followed by dialysis fluid slag, acid extracted the alcohol liquid part of the higher content of Zn content of about 20% in. Cd elements: kelp in Cd content is lower than that the Sargasso of Cd content. Cd content in kelp highest acid extraction component, which accounted for 36.10% of the total acid extraction and alcohol liquid part, followed by retention solution, there is a higher Cd. Sargasso Cd is primarily in the alcohol component is extracted, the total content of 52.72%, including higher levels of alcohol liquid part, accounting for 25.28%. Sargasso alkali extraction and alcohol solution and acid extraction and alcohol precipitation section also contains a higher content of Cd. The Pb elements: Kelp Pb content is lower than that the Sargasso of Pb content. Kelp in the Pb mainly alkali extraction component, accounting for 48.2%, the highest part of the content of alcohol precipitation; mainly in the Sargasso of Pb in water extraction component, the total content of 44.13%.
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