中孔洞碳材的合成、表面改質及重金屬吸附之研究

Synthesis, surface-modification of mesoporous carbon materials and their application on selective adsorption of heavy metal

劉世淼(Shih-Miao Liu)

指導教授 ： 鄭吉豐

中原大學/理學院/化學研究所/博士(2011年)

https://doi.org/10.6840/cycu201100121

摘要

本論文製備具有高表面積之規則排列中孔洞碳材，並以中孔洞碳材當作載體，透過表面改質方式將含不同O、N、S和NS雙功能複合之螯合物導入中孔洞碳材並對於重金屬吸附能力及選擇性進行探討。首先將先製備具有高表面積之中孔洞碳材當作載體，並以硝酸進行表面改質將含氧官能基導入中孔洞碳材，然後利用SOCl2將碳材表面含氧官能基氯化，將不同N數多胺類藉由表面改質方式導入中孔洞碳材，最後進行重金屬吸附能力及選擇性的探討。本論文除了使用不同含N數的多胺類螯合物二乙烯三胺、三乙烯四胺、四乙烯五胺、五乙烯六胺以外，並嘗試以高分子型多胺類聚乙烯亞胺進行表面改質，結果顯示中孔洞碳材經過表面改質後對於重金屬Hg2+吸附具有顯著的吸附能力和獨特的選擇性。此外，為了探討pH值對於重金屬Hg2+吸附的影響，嘗試改變pH值範圍1.5-6，多胺類表面改質中孔洞碳材至少要達到pH 4才能完全顯現出重金屬Hg2+的吸附能力，因此，pH值在重金屬Hg2+的吸附應用上扮演著舉足輕重的角色。在重金屬Hg2+最高吸附量能力方面，改變不同含N數多胺類表面改質中孔洞碳材最高吸附量可高達528mg/g，最後本論文嘗試將實驗數據以Langmuir和Freundlich兩種等溫吸附方程式和三種動力學模式Pseudo first-order rate equation、Pseudo second-order rate equation及intraparticle diffusion equation進行曲線擬合，探討Hg2+在改質後中孔洞碳材吸附平衡及動力學行為。

關鍵字

選擇性 ； 中孔洞碳材 ； 重金屬 ； 多胺類 ； 汞

並列摘要

Ordered mesoporous carbon material with high surface area containing nitrogen, sulphur or NS bifunctional composite functional groups was synthesized by sol-gel process to enhance the adsorption capacity and selectivity of heavy metals from aqueous environment. With modification of the product using different kinds of multi-amine ligands such as Diethylenetriamine, Triethylenetetraamine, Tetraethylenepentamine, Pentaethylenehexamine, and poly(ethyleneimine), the results showed that through modification of mesoporous carbon materials the adsorption capacity gave a significant and unique selectivity for heavy metal Hg2+ adsorption. In addition, correlation between pH and adsorption was investigated by treating the modified mesoporous carbon materials with varying the pH values from 1.5-6. The optimum adsorption capacity of modified mesoporous carbon for Hg2+ adsorption showed at pH 4, thus, pH value application on heavy metal Hg2+ adsorption plays an important role. Given the results on different ligands, poly(ethylene) gave the highest absorption of 528 mg/g which can be attributed to the number of nitrogen available that can be attracted to heavy metal Hg2+. It can be deduced that the maximum adsorption capacity of the mesoporous carbon materials would be determined by the number of available nitrogen. Furthermore, Langmuir and Freundlich isotherms were performed as well as the three kinetic models namely pseudo first-order rate equation, pseudo second-order rate equation and the intraparticle diffusion equations for curve fitting of Hg2+ in the modified mesoporous carbon material in the adsorption equilibrium and dynamics.

並列關鍵字

selectivity ； multi-amine ； mercury ； heavy metal ； mesoporous carbon

參考文獻

1. Cheng, P. Z.; Teng, H. Carbon 2003, 41, 2057.

2. Pradhan, B. K.; Sandle, N. K. Carbon 1999, 37, 1323.

8. Li, H.; Xi, H. A.; Zhu, S.; Wen, Z.; Wang, R.; Microporous Mesoporous Mater. 2006, 96, 357.

9. A. EDWIN VASU, Vol. 5, No.4, 2008, 814-819.

12. Krystyna Pyrzyńska and Michał Bystrzejewski, Colloids and Surfaces A: Physicochem. Eng. Aspects 2010, 362, 102–109.