Sharif Digital Repository

Polyvinylpyrrolidone coated nano zero valent iron-copper (PVP-nZVI-Cu) bimetallic nanoparticles were successfully synthesized for dechlorination of trichloroethylene (TCE) into non-toxic byproducts in the presence of persulfate oxidant. The average size of PVP-nZVI-Cu nanoparticles (3-25 nm) was smaller than PVP-nZVI (25-60 nm) and nZVI (50-90 nm) particles due to PVP role in the prevention of iron aggregation and agglomerations. The synthesized PVP-nZVI-Cu nanoparticles were used as an efficient persulfate (PS) activator to generate reactive oxygen species (ROSs) for the degradation of TCE. The complete removal of TCE (99.6%) was achieved in the presence of 0.4 g/L of PVP-nZVI-Cu... 

A series of superabsorbent composites were synthesized through graft copolymerization of acrylic acid (AA) onto carboxymethyl cellulose (CMC) in the presence of celite powder using N,N'-methylenebisacrylamide (MBA) as a cross-linking agent and ammonium persulphate (APS) as an initiator. The chemical structure and thermal properties of the composite hydrogels were characterized by FTIR spectroscopy and TGA methods, respectively. Morphology of the samples was examined by scanning electron microscopy (SEM). In free-state, the swelling conditions and hence the related data are not real, because in all their applications the swelling particles of superabsorbent must absorb aqueous solutions while... 

A novel catalyst of sulfidated iron-nickel supported on biochar (S-FeNi@BC) was synthesized to activate persulfate (PS) for the removal of trichloroethylene (TCE). A number of techniques including XRD, SEM, TEM, FTIR, BET and EDS were employed to characterize S-FeNi@BC. The influence of sulfur to iron ratio (S/F) on TCE removal was investigated by batch experiments and a higher TCE removal (98.4%) was achieved at 0.22/1 ratio of S/F in the PS/S-FeNi@BC oxidation system. A dominant role in iron species conversion was noticed by the addition of sulfur in FeNi@BC system. Significant enhancement in recycling of the dissolved and surface Fe(II) was confirmed which contributed to the generation of...