Synthesi s of NiO nanoparticles by precipitation method a nd their application as an effective adsorbent in the removal of Cr(VI) from aqueous solutions

Chrom ium is wid ely used in industrial applications such as metallurgy, battery, paper and paint manufacturi ng. Chromium exists in the environment both as trivalent [Cr(III)] and hexavalent [Cr(VI)] forms. H owever, th e hexavalent form is ۵۰ ۰ times more toxic tha n the trivalent form. A number of technologie s have been used for removal of h eavy metals from aqueous solutions, such as coagulation/flocculation, membrane filtration, o xidation, re verse osmosis, ion exc hange and adsorption processes [۱ ]. In the rec ent years t here has been an increasing interest in the synt hesis of nanosized crystalline metal oxides beca use of their large surface areas, unusual adsorptive properties, surface defects and fast diffusi vities. NiO is one of these metal ox ides and ex hibits adsorption capac ity for sev eral ions. Therefore the NiO nanoparticles may be used to control the mobility of metal ions in the environment [۲,۳]. In th is work NiO nanoparticles have been synthesized by precipitation method and charac terized by XRD and TEM techniques. The efficiency of this nanoparticlese have been studied in the removal of Cr(V I) from aqueous solutio ns.

کلیدواژه ها:

Adsorption ، Cr(V I) ، NiO nanoparticles ، P recipitation