Immobilization of Ag nanoparticles on porous carbon prepared via carbonization of red water using Caesalpinia gilliesii flower extract

In recent years, carbon materials have obtained from carbonization or pyrolysis of agricultural waste products followed by chemical activation using dehydrating agentsand physical activation in the presence of such as air, steam or carbon dioxide as oxidizing gases [1]. Because of singular structure, improved accessibility of active sites for reactants and appropriate electronic conductivity of carbon structures, these materials have been used as catalyst, support and adsorbents for gases or metal species.Immobilization of metal nanoparticles on the surface of inorganic supports decreases agglomeration of nanoparticles which leads to more stability and higher reactivity ofsupported nanoparticles [2]. In this work, a carcinogenic waste product in the industrial unit of 2,4,6-trinitrotluene (TNT) production was converted to a stable support. The facile preparation of porous carbon and its Fe3O4 nanocomposite were performed by carbonization of red water and co-precipitation technique, respectively. Then, the flower extract of C. gilliesii was used for reduction of Ag+ ions and stabilization of the preparead Ag nanoparticles on the surface of porous carbon and C/Fe3O4 nanocomposite. The asprepared carbon nanocomposites were characterized by different methods and showed good activity in the reduction of methyl orange and 4-nitrophenol as toxic organic compounds.