Prepation of the superparamagnetic iron oxide nanoparticles modified with polyamidoamin dendrimers and using them in adsorption of some heavy metals and dyestuffs

In this study, two new adsorbents based on superparamagnetic iron oxide nanoparticle were synthesized and they were employed for the removal of some heavy metals and dyes from aqueous solution. First, Fe3O4 nanoparticles were prepared for the synthesis of adsorbents. Then, Fe3O4 was coated with silica and aminopropyltriethoxysilane to ensure the stability of the nanoparticles. After coating, the nanoparticles were modified with polyamidoamine dendrimer and ammonium purpurate to obtain the first adsorbent. Modification with polyamidoamine dendrimer and ammonium purpurate was repeated for the second time and a second adsorbent was obtained. The synthesis of the adsorbents has been proved by the characterization processes after each step. Both adsorbents were used to remove Pb (II), Ni (II), Co (II) and Cr (III) heavy metals and Alizarin Yellow and Eriochrom Black T dyestuffs from aqueous solution. The effects of contact time, temperature, pH, adsorbent amount and initial concentration to the adsorption were investigated and adsorption datas were evaluated to Langmuir and Freundlich adsorption isotherms. Langmuir and Freundlich constants were calculated. In addition, kinetical datas obtained as a result of experimental studies were applied to Pseudo first and second order kinetic equations and rate constants of adsorptions were calculated. According to the results of the study, adsorbents were effective in removing both heavy metals and dyestuffs. Following the completion of adsorption processes, the antibacterial effect of nanoparticles synthesized in the thesis study was also investigated. Antibacterial effects were determined by dilution method using 9 different bacterias. It has proven that the nanoparticles synthesized in this study have also anti-bacterial effects against some bacterias. Keywords: Iron Oxide Nanoparticles, PAMAM, Adsorption, Murexide, Heavy Metal, Dyestuff, Dendrimer, Antimicrobial effect.