Removal behavior and mechanism of Co(II) on the surface of Fe–Mn binary oxide adsorbent

Efficient removal of 17α-ethinylestradiol (EE2) from water using freshly formed Fe–Mn binary oxide

“…The specic surface area of the synthetic materials were measured by nitrogen adsorption using the Brunauer-Emmett-Teller (BET) method with a Micromeritics ASAP 2000 surface area analyzer (Norcross, GA, USA). According to our previous study, 30 the surface area of the FMBO, manganese dioxide and iron oxide were 316.76 m 2 g À1 , 266.90 m 2 g À1 and 172.31 m 2 g À1 , respectively. A zeta (z) potential analyzer (Zetasizer 2000, Malvern, UK) was used to mensurate the pH zpc of Fe-Mn binary oxide particles (6.02), manganese dioxide (2.85) and iron oxide (7.45).…”

“…38 The surfaces of FMBO is positively charged when the pH was lower than the pH zpc value of FMBO (6.02) and negatively charged at pH > 6.02. 30 At pH < 5, FMBO showed a lower removal rate than the maximum, and it may be because the oxide particles were partly dissolved in strong acidic solution. Besides, the lower removal efficiency at pH < 5 may also partly related to the competition with H + which reduced the adsorption of EE2 on adsorbent.…”

“…A zeta (z) potential analyzer (Zetasizer 2000, Malvern, UK) was used to mensurate the pH zpc of Fe-Mn binary oxide particles (6.02), manganese dioxide (2.85) and iron oxide (7.45). 30 Fourier transform infrared spectroscopy (FTIR) spectra were obtained using a Nicolet 6700 Fourier Transform IR spectrophotometer Spectrum (Thermo, USA) to identify functional groups on the oxide surface before and aer removing EE2. FTIR spectra from 400 to 4000 cm À1 were obtained with 15 scans for each spectrum recorded at a resolution of 4 cm À1 .…”

“…57 These peaks disappeared aer removing EE2, and a new peak appeared at 1060 cm À1 , which was attributed to the C-O angular deformation on FMBO 58 as a result of the hydrogen bonding effect. Additionally, a peak due to the stretching vibration peak of M-O (Fe-O and Mn-O) blue shied from 484 to 567 cm À1 aer reaction with EE2, indicating the decrease of manganese oxide 30,50,59 that reduced to Mn 2+ in the solution. In conclusion, EE2 was adsorbed by the effect of hydrogen bonding.…”

Removal of Hg(ii) in aqueous solutions through physical and chemical adsorption principles

“…53 Binary oxides with surface charge and variable valence elements have higher surface activities than single oxides and can take advantage of both unique properties of them. 54 Ali et al studied the adsorption capacities of binary oxides and found that nanoparticles containing silver and zinc had better performance than singe silver or zinc oxide. 55 Fe, Mn, Zn and Ag oxides, for their high surface activity and modiability, are promised to be the new generation of environmental remediation materials.…”