Adsorption Behavior Of Cu(?) On New Magnetic Materials

Copper,with good physical and chemical properties,has been widely used in electroplating,fertilizer,dyes,metallurgy and other industries.However,the rapid development of these industries has resulted in the accumulation of Cu???,which does enormous damage to both the environment and local people's health.How to effectively remove heavy metal materials has become the priority to be settled down in today's environmental protection.Based on this problem,a new type of magnetic material was prepared and the adsorption behavior of copper was studied.The main research contents and experimental results are as follows:1.The magnetic polyaniline/graphene oxide?MPANI/GO?composites were synthesized by using aniline and GO.The adsorption of Cu???on the MPANI/GO composites were studied as a function of pH,contact time,ionic strength,foreign cation and anion ions.The results showed that the adsorption kinetic can be well described by the pseudo-second-order model.The Cu???adsorption was strongly dependent on pH,and independent of ionic strength,indicating that the adsorption of Cu???was mainly domonated by outer-sphere surface complexation at low pH,and by inner-sphere surface complexation and precipitation at high pH.The adsorption isotherms can be well described by the Langmuir model.The thermodynamic parameters calculated from temperature-dependent adsorption isotherms indicated that the adsorption process was endothermic and spontaneous.The results showed that the MPANI/GO composites were effective materials for the removal of Cu???from aqueous solutions and could be separated by using magnetic separation method in the practical applications.2.Fe₃O₄@ hexadecyl trimethoxysilane@ chitosan?Fe₃O₄@C16@CTS?composites were synthesized by hexadecyl trimethoxysilane,chitosan and Fe₃O₄.The adsorption of Cu???on the Fe₃O₄@C16@CTS composites were studied as a function of pH,contact time,ionic strength,foreign cation and anion ions.The results showed that the Fe₃O₄@C16@CTS composites had a higher adsorption capacity and the adsorption kinetic can be well described by the pseudo-second-order model.The Fe₃O₄@C16@CTS composites was strongly dependent on pH and independent of ionic strength,indicating that the adsorption of Cu???was mainly domonated by outer-sphere surface complexation at low pH,and by inner-sphere surface complexation and precipitation at high pH.The adsorption isotherm was well described by the Langmuir model,with a maximum adsorption capacity of 261.78 mg/g at pH = 5.8 ± 0.1 and T = 298 K.The results showed that the Fe₃O₄@C16@CTS composites were potential materials for the removal of Cu???from aqueous solutions and could be separated by a simple magnetic separation method in wastewater treatment.Both of the adsorbents showed good adsorption properties for copper adsorption.On the one hand,the adsorption capacity of Fe₃O₄@C16@CTS composites composites was higher than that of MPANI/GO composites.On the other hand,CTS is cheaper than GO.Therefore,Fe₃O₄@C16@CTS composites with lower price and a higher adsorption capacity will have broader prospects for application.