含鐵廢酸資源化製備奈米氧化鐵及氧化鐵/矽砂吸附重金屬之複合材料研究

Preparation of nano iron oxide from recycled waste pickle acid and its heavy metal adsorption study by the coating on silica sand

陳韋翰(Wei-Han Chen)

指導教授 ： 王竹方

國立清華大學/原子科學院/生醫工程與環境科學系/碩士(2012年)

摘要

本研究將含鐵廢酸資源化製備成奈米氧化鐵矽砂複合材料，應用在重金屬與放射性核種之吸附研究。研究過程中嘗試利用交流熱電漿技術製備磁性不同之γ相氧化鐵(γ–Fe2O3)和α相氧化鐵(α–Fe2O3)。在熱電漿作用過程中，γ–Fe2O3會逐漸轉換成α–Fe2O3，因此可由順磁性大小之改變分辨樣品中γ–Fe2O3和α–Fe2O3的比例。使用異相懸浮法製備之氧化鐵覆膜矽砂(IOCS)，被用來吸附廢水樣品中重金屬(鉻(VI), 鉛(II), 鎳(II), 鋅(II), 鎘(II), 鈷(II), 鍶(II)與銫(I))等金屬離子，研究發現IOCS對於重金屬鉻(VI), 鉛(II), 鎳(II), 鋅(II), 鎘(II), 鈷(II)具有較佳的吸附效果，而對於鍶及銫元素的吸附能力則較弱。吸附後之IOCS利用電漿熔融技術玻璃化。

關鍵字

資源化 ； 氧化鐵 ； 電漿 ； 玻璃化

並列摘要

In the study, the iron containing waste acid was applied to recycle nano iron oxide materials in preparing a Fe/Si absorbent for the adsorption study. The recycled iron oxide material is compatible to reagent grade. It has similar paramagnetic properties and purity. Recently, Magnetic nanoparticles have attracted a great deal of attention due to their versatile applications as in advanced functional materials on high-density recording media, biomedical, magnetic fluids, catalysts and adsorbents etc. Iron oxide nanoparticles have many merits compared to other nanoparticles such as less toxicity, bio compatible and more chemically stable. Hence, it is worthy to address our investigation toward the characteristics of these nanoparticles. Conventionally, iron oxide nanoparticles have been prepared by aqueous solution method, which involved the oxidation and reduction reaction of ferrous and ferric ions. However more and more preparation methodologies have been developed for nanoparticle synthesis. Among those, some are thermal plasma reactions. In this studies, a fast track AC thermal plasma methodology is involved in the synthesis of γ–Fe2O3 and α–Fe2O3 from ferrous waste acid.

During the thermal plasma treatment, the crystallite of γ–Fe2O3 will transform to α–Fe2O3 by the evident of paramagnetic strength disappearance. Therefore we have developed a unique technique to distinguish the ratio of γ–Fe2O3 and α–Fe2O3 in its mixture. Preparation and characterization of silica coated with iron oxides are described in the study. A heterogeneous reaction is employed to coat γ–Fe2O3 and α–Fe2O3 on silica sands (IOCS). The adsorption of heavy metal ions (Cr(VI), Pb(II), Ni(II), Zn(II), Cd(II)) and radionuclides (Co(II), Sr(II), Cs(I)) through modified IOCS is examined. The adsorption result for heavy metals group is strong. As for radionuclide adsorption study, only cobalt has strong adsorption on IOCS surface. Strontium and Cesium are weakly adsorbed on IOCS surface. The plasma vitrefication experiments toward radionuclide adsorbed by IOCS explained the feasibility of radioactivity fixation.

參考文獻

3. A. Mersmann, M. A., Chem. Eng. Technol 1994, 17, 1-9.

4. A. F. Wells, Annu. Rep. Chem. Soc. 1946, 43, 62.

7. T. Ozdemir, C. O., Chem. Eng. Commun 2006, 193, 548-563.

10. K. Moustakas, D. F., J. Hazard. Mater. 2005, 123, 120-126.

11. (a) G. Soucy, R. B., High Temp. Mater. Processes 1998, 2, 195-206; (b) H.S. Park, C. G. K., J. Ind. Eng. Chem. 2006, 12, 216-223.