| Recently, with the rapid development of economic construction, water pollution caused by industrialization becomes increasingly serious. Due to heavy metal ions general have greater toxicity, high mobility and low toxic concentration, and they are not biodegradable, some heavy metals and fluorion can turn to be more harmful compounds by microbial action.The enrichment of heavy metal ions in the body mainly through drinking water or the food chain, worsly, it may cause death. Therefore, the water pollution of heavy metal ions becomes one of the most serious environment problems. The environmental protection workers are trying to find a scientific and effective method to remove the heavy metal ions from water.Among the water purification processing technology of micro pollutants, adsorption is a simple, promising method and has been widely applied. In this paper, the adsorption properties and adsorption mechanism of several kinds of marine biological materials or their composite materials in the water was studied.Different drying methods were used to prepare chitosan beads and fibers. We found that the freeze dried chitosan fiber (F-CSX) has higher adsorption capacity than other adsorbents. The results obtained from the equilibrium isotherms adsorption studies of Cu(II) ions by being analyzed in two adsorption models, namely, Langmuir, Freundlich isotherm equations, the maximum adsorption capacity of F-CSX as obtained from Langmuir isotherm equation was found to be 64.52mg/g. Thermodynamic study indicated that the adsorption process was an endothermic reaction.The adsorption of Cu2+ by Alginate/porous silicon composite material and pure porous silicon powders were studied. The adsorption results showed that the adsorption capability of copper by Alginate/porous silicon composite material is superior to that of pure porous silicon powders, and the adsorption rate is significantly larger than the powders.A new environment-friendly adsorption material was prepared by oxidation of Enteromorpha using KMnO4(KMnO4-EP) in laboratory, The adsorption results showed that the adsorption capacity of KMnO4-EP was much higher than nature Enteromorpha. The maximum adsorption capacity of KMnO4-EP as obtained from Langmuir isotherm equation was found to be 108.70mg/g at temperature of 60℃. Thermodynamic study indicated that the adsorption process was an endothermic reaction. A batch adsorption system was applied to investigate the adsorption of fluoride from aqueous solution by graphene. The experimental results showed that the fluoride adsorption capacity of graphene is excellent and can reach 18.01 mg/g at initial fluoride concentration of 25mg/L and at temperature of 25℃. The kinetic studies showed that the adsorption process was very fast and 97.71% removal of fluoride has been achieved within 3 min at initial fluoride concentration of 25mg/L and at temperature of 25℃. The isotherm analysis indicated that the adsorption data can be represented by both Freundlich and Langmuir isotherm models. Thermodynamic studies revealed that the adsorption reaction was a spontaneous and endothermic process. |
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