Yale University, Department of Chemical and Environmental Engineering, Mason Lab, 9 Hillhouse Ave, New Haven, CT 06511, United States.
University of Connecticut, Department of Civil and Environmental Engineering, Castleman Building, 261 Glenbrook Road, Storrs, CT 06269, United States.
J Hazard Mater. 2016 Jun 5;310:117-24. doi: 10.1016/j.jhazmat.2016.01.078. Epub 2016 Feb 8.
Nano metal oxides are of interest for aqueous selenium (Se) remediation, and as such, nano-hematite (nα-Fe2O3) was examined for use as a Se adsorbent. The effect of surface area on adsorption was also studied. nα-Fe2O3 particles were synthesized from Fe(NO3)3 and FeCl3 via forced hydrolysis. The resulting particles have similar sizes, morphologies, aggregate size, pore size, and PZC. The nα-Fe2O3 from FeCl3 (nα-Fe2O3-C) differs from the nα-Fe2O3 from Fe(NO3)3 (nα-Fe2O3-N) with a ∼25±2m(2)/g greater surface area. Selenite Se(IV) adsorption capacity on nα-Fe2O3 has a qmax ∼17mg/g for the freeze-dried and re-suspended nα-Fe2O3. The Δqmax for nα-Fe2O3 from Fe(NO3)3 and FeCl3 that remained in suspension was 4.6mg/g. For selenate Se(VI), the freeze-dried and re-suspended particles realize a Δqmax= 1.5mg/g for nα-Fe2O3 from Fe(NO3)3 and FeCl3. The nα-Fe2O3 from Fe(NO3)3 and FeCl3 that remained in suspension demonstrated Se(VI) Δqmax=5.4mg/g. In situ ATR-FTIR isotherm measurements completed for Se(VI) at a pH 6 suggest that Se(VI) forms primarily outer-sphere complexes with nα-Fe2O3 synthesized from both salts.
纳米金属氧化物因其在水相中修复硒（Se）的应用而受到关注，因此，纳米赤铁矿（nα-Fe2O3）被用作 Se 吸附剂进行了研究。还研究了表面积对吸附的影响。nα-Fe2O3 颗粒是通过强制水解从 Fe(NO3)3 和 FeCl3 合成的。得到的颗粒具有相似的粒径、形貌、团聚体大小、孔径和 PZC。nα-Fe2O3-C 与 nα-Fe2O3-N 相比，表面积大了约 25±2m(2)/g，nα-Fe2O3-N 来自 Fe(NO3)3，nα-Fe2O3-C 来自 FeCl3。冻干后再悬浮的 nα-Fe2O3 的 Se(IV)吸附容量达到 17mg/g。nα-Fe2O3 来自 Fe(NO3)3 和 FeCl3 的悬浮液的 Δqmax 为 4.6mg/g。对于 Se(VI)，冻干后再悬浮的颗粒在 nα-Fe2O3 上实现了 Δqmax= 1.5mg/g，nα-Fe2O3 来自 Fe(NO3)3 和 FeCl3。悬浮液中的 nα-Fe2O3 来自 Fe(NO3)3 和 FeCl3 的 Se(VI) Δqmax 为 5.4mg/g。在 pH 6 下完成的 Se(VI)原位 ATR-FTIR 等温线测量表明，Se(VI)主要与两种盐合成的 nα-Fe2O3 形成外球络合物。
