Development of ceramic grade red iron oxide pigment from waste iron source

Ceramic grade red iron oxide (alpha-Fe2O3) nanoparticles pigments have been synthesized from waste condensed milk containers which contain a prominent amount of iron (93.2%). The synthesis method comprised of two steps: in the first step ferrous sulfate was prepared following an acid leaching method; while the second step was oxidation and calcination of ferrous sulfate to pro-duce desired alpha-Fe2O3 in nano form. The structure, functional groups, chemical state, morphology, particle size, surface area, elemental, thermal analysis and magnetic properties of the samples were investigated using XRD, FTIR, XPS, SEM, BET, EDS, TG-DT and VSM respectively. Pure hematite (alpha-Fe2O3) phase was confirmed by XRD and the average crystal sizes were in the range 34-126 nm have been performed by Debye-Scherer's formula, which are consistent with the results as achieved from SEM images. Agglomerated irregular spherical nanoparticles (45-149 nm) were found in SEM image. The surface chemistry and the chemical state (Fe3+) of the he-matite nanoparticles was also confirmed by XPS. The mesoporous nature of the nanoparticles with high surface area were measured by BET and it has been revealed that the BET specific surface area (33.55 m2/g) was marginally higher than the commercial one. The magnetic nature of the nanoparticles was portrayed by VSM and the nanoparticles showed the ferromagnetic behavior. Moreover, particle size distributions and zeta potential values have been also measured by DLS.

Automated summary

Ceramic grade red iron oxide (alpha-Fe2O3) nanoparticles pigments were synthesized from waste condensed milk containers with high iron content (93.2%). The synthesis process included preparation of ferrous sulfate through acid leaching, followed by oxidation and calcination to obtain nano alpha-Fe2O3. The samples were characterized using various techniques to investigate their structure, functional groups, chemical state, morphology, particle size, surface area, elemental composition, thermal properties, and magnetic behavior.