Department of Chemical Engineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247 667, India.
Environ Sci Pollut Res Int. 2019 Apr;26(11):10631-10640. doi: 10.1007/s11356-019-04528-0. Epub 2019 Feb 15.
This research work aims to develop a biomaterial entrapped with iron nanoparticles by green synthesis method in which biomass act as both reducing and capping agent. Iron nanoparticles embedded in Citrus limetta peels were characterised using ICP-MS for determination of metal loading, XRD, XPS for crystallinity and oxidation states, TEM followed by FESEM-EDS for particle size and morphology. Sizes of nanoparticles were found to be in the range of 4-70 nm. Batch experiments were conducted to study the effect of different parameters such as contact time, amount of biomaterial and volume of chromium(VI) solution for 2500 mg L of Cr(VI). Complete reduction was attained for a contact time of 5 min with 1.5 g of biomaterial for initial concentration of 2500 mg L. The experimental results inferred that 1 g of biomaterial completely reduced 33 mg of hexavalent Cr to trivalent Cr. XRD and XPS revealed that iron nanoparticles are in amorphous form while XPS confirms Fe state. The transition of Fe to Fe/Fe during the treatment with chromium solution confirms the reduction of Cr to Cr.
本研究旨在通过绿色合成方法制备一种负载铁纳米粒子的生物材料，其中生物质同时作为还原剂和稳定剂。用 ICP-MS 测定金属负载量、XRD、XPS 测定结晶度和氧化态、TEM 结合 FESEM-EDS 测定粒径和形貌对负载于柑橘皮中的铁纳米粒子进行了表征。纳米粒子的尺寸范围为 4-70nm。进行了批实验以研究不同参数的影响，如接触时间、生物材料的用量和 2500mg/L Cr(VI)溶液的体积。对于初始浓度为 2500mg/L 的 Cr(VI)，接触时间为 5min 时即可达到完全还原。实验结果表明，1g 生物材料可将 33mg 六价 Cr 完全还原为三价 Cr。XRD 和 XPS 表明铁纳米粒子呈非晶态，而 XPS 则证实了 Fe 的存在。在与铬溶液处理过程中，Fe 向 Fe/Fe 的转变证实了 Cr 的还原。
