الفهرس 
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Abstract
The presence of heavy metals in waste water causes a threat to the lives of humans and aquatic environment. Different techniques have been used for the removal of heavy metals from polluted water stream, examples include: chemical precipitation, oxidation and reduction, ion exchange, adsorption and biosorption. Using biosorbents such as yeast, microorganisms, seaweeds, shells of crustaceans and crabs have been gaining special interest. This interest was due to their ability to remove heavy metals from waste water efficiently and to their low cost compared to activated carbon and alumina. In the present work, biosorption using various biosorbents such as (shrimp shells, treated shrimp shells, treated mussel shells and mussels shells) was investigated. The latter biosorbent has not been used before. All the aforementioned biosorbents were investigated for their ability to remove Cu(lI) ions from aqueous by batch experiments. Different variables were studied for their effect on the degree of removal of Cu(lI) ions such as: the initial concentration of copper sulphate pentahydrate, the particle size of the ’different biosorbents, the type of biosorbent, and the temperature during biosorption and the pH of the salt solution. After examining the effects of the previous variables, the normal adsorption isotherms, Freundlich, and Langmuir isotherms were plotted for each variable and the results were interpreted. It was found from the results that the biosorption in the majority of cases was multilayered as shown by the isotherms. In addition, it was found in general• that the Freundlich isotherm is obeyed while the Langmuir is not obeyed expect in some cases. It was found that the rate of adsorption varied inversely with the particle size, which mean that the small particle size gave better results. Treated mussels shells were the best in general for removing Cu(lI) from aqueous solution except in some cases. High temperatures, gave worse results than room temperature, which meant that biosorption is inversely proportional to the solution temperature and that the process is exothermic which presented a saving in energy. Higher concentrations gave lower percent extraction than lower concentrations. Finally lowering the pH of the copper sulphate pentahydrate solution gave worse results than the higher pH which mean that basic media is less favorable than acidic media.