School of Chemical Engineering of Sichuan University, Chengdu, 610065, PR China; Engineering Research Center of Comprehensive Utilization and Clean Processing of Phosphorus Resources, Ministry of Education, Chengdu, 610065, PR China.
School of Chemical Engineering of Sichuan University, Chengdu, 610065, PR China; College of Chemistry and Chemical Engineering, Yibin University, Yibin, 644000, PR China.
Ecotoxicol Environ Saf. 2020 Sep 1;200:110744. doi: 10.1016/j.ecoenv.2020.110744. Epub 2020 May 24.
Hematite nanoparticles (α-FeO NPs) were successfully synthesized by a low-cost solvent-free reaction using Ferrous sulfate waste (FeSO·7HO) and pyrite (FeS) as raw materials and employed for the decolorization of Methyl Orange by the photo-Fenton system. The properties of α-FeO NPs before and after photo-Fenton reaction were characterized by X-ray powder diffraction (XRD), Field emission scanning electron microscopy (FESEM), Fourier transform infrared (FT-IR) spectrum and X-ray photoelectron spectroscopy (XPS), and the optical properties of α-FeO NPs were analyzed by UV-vis diffuse reflectance spectra (UV-vis DRS) and Photoluminescence (PL) spectra. The analytic results showed that the as-formed samples having an average diameter of ~50 nm exhibit pure phase hematite with sphere structure. Besides, little differences were found by comparing the characterization data of the particles before and after the photo-Fenton reaction, indicating that the photo-Fenton reaction was carried out in solution rather than on the surface of α-FeO NPs. A 2 central composite design (CCD) coupled with response surface methodology (RSM) was applied to evaluate and optimize the important variables. A significant quadratic model (P-value<0.0001, R = 0.9664) was derived using an analysis of variance (ANOVA), which was adequate to perform the process variables optimization. The optimal process conditions were performed to be 395 nm of the light wavelength, pH 3.0, 5 mmol/L HO and 1 g/L α-FeO, and the decolorization efficiency of methyl orange was 99.55% at 4 min.
赤铁矿纳米粒子（α-FeO NPs）通过使用硫酸亚铁废料（FeSO·7HO）和黄铁矿（FeS）作为原料的无溶剂反应，成功地合成了，并用在光芬顿体系中对甲基橙进行脱色。α-FeO NPs 在光芬顿反应前后的性能用 X 射线粉末衍射（XRD）、场发射扫描电子显微镜（FESEM）、傅里叶变换红外（FT-IR）光谱和 X 射线光电子能谱（XPS）进行了表征，并通过紫外-可见漫反射光谱（UV-vis DRS）和光致发光（PL）光谱分析了α-FeO NPs 的光学性质。分析结果表明，形成的样品具有平均直径约为 50nm 的纯相赤铁矿，具有球形结构。此外，通过比较光芬顿反应前后颗粒的表征数据，发现几乎没有差异，这表明光芬顿反应是在溶液中而不是在α-FeO NPs 表面进行的。采用中心复合设计（CCD）与响应面法（RSM）相结合，对重要变量进行评价和优化。通过方差分析（ANOVA）得出了一个显著的二次模型（P 值<0.0001，R=0.9664），该模型足以进行过程变量的优化。优化后的工艺条件为：波长 395nm、pH 3.0、5mmol/L HO 和 1g/L α-FeO，在 4min 内对甲基橙的脱色效率达到 99.55%。
