沸石咪唑酯骨架-8 (ZIF-8)應用於電容去離子(CDI)系統

Zeolite-like imidazole framework material (ZIF-8) applied in capacitive deionization (CDI) system

辜鎮遠(Chen-Yuan Ku)

指導教授 ： 彭晴玉

淡江大學/工學院/水資源及環境工程學系碩士班/碩士(2023年)

https://doi.org/10.6846/TKU.2023.00052

摘要

電容去離子(Capacitive Deionization, CDI)是利用施加電壓，使離子定向移動的技術，具有低耗能、產水率高、無二次污染等優點。常用於CDI系統的電極材料包括:活性碳、奈米碳管、石墨烯等，而沸石咪唑酯骨架材料(Zeolitic Imidazolate Framework, ZIF)則是近幾年新興的電極材料。本研究選擇ZIF-8應用於CDI系統，首先探討不同鋅源(硝酸鋅或醋酸鋅)對ZIF-8合成及應用於CDI系統的成效；接著以高溫碳化(400-800 oC) ZIF-8，並探究高溫碳化之ZIF-8應用於CDI系統之可行性。
使用硝酸鋅合成的ZIF-8 (ZN-ZIF-8)具有明確的顆粒狀，將5% ZN-ZIF-8與GAC混合，可由GAC原本的比電容值41.83 F/g提高至46.23 F/g，GAC+5% ZN-ZIF-8 CDI表現與GAC電極相比，Na+去除率提升5.3%，Na+電吸附量可由原始GAC之56.31 μmole Na+/g 提高至99.69 μmole Na+/g。
以5-20% ZN-ZIF-8與GAC混合，GAC+15% ZN-ZIF-8的比電容值可達49.26 F/g，CDI表現與GAC電極相比，GAC+10% ZN-ZIF-8 之Na+去除率提升了7.83%，電吸附量是從43.01 μmole Na+/g 提高至121.12 μmole Na+/g。
高溫碳化(400、500、600、700、800 oC) ZIF-8的研究中，ZIF-8_800的比電容值可達66.73 F/g，ZIF-8_700有最佳的CDI表現，電吸附量由120.15 μmole Na+/g 提高至136.44 μmole Na+/g。
ZIF-8應用於CDI系統深具潛力，可以添加適當比例的ZIF-8與GAC混合或是高溫碳化之ZIF-8製成CDI電極，可有效提升Na+與Cl-之去除。

關鍵字

電容去離子 ； 沸石咪唑酯骨架材料 ； ZIF-8 ； 高溫碳化 ； 硝酸鋅

並列摘要

Capacitive deionization (Capacitive Deionization, CDI) is a technology that applies voltage to move ions in a CDI reactor. It has the advantages of low energy consumption, high water production rate, and no secondary pollution. Electrode materials commonly used in CDI systems include activated carbon, carbon nanotubes, graphene, etc. Zeolitic Imidazolate Framework (ZIF) is an emerging electrode material in recent years. In this study, ZIF-8 was selected as electrode material to be applied in the CDI system. Firstly, the effects of different zinc sources (zinc nitrate or zinc acetate) on the synthesis of ZIF-8 and its application in the CDI system were investigated; Secondly, explore the feasibility of applying high temperature carbonized ZIF-8 to CDI system.
ZIF-8 synthesized with zinc nitrate (ZN-ZIF-8) has distinct granular shape. Mixing 5% ZN-ZIF-8 with GAC can increase the specific capacitance value of GAC from 41.83 F/g to 46.23 F/g. GAC+5% ZN-ZIF-8 had better performance compared with GAC electrode applied in CDI; the Na+ removal efficiency increased by 5.3%, and the electrosorption capacity increased from 56.31 μmole Na+/g to 99.69 μmole Na+/g .
GAC mixed with 5-20% ZN-ZIF-8, the specific capacitance value of GAC+15% ZN-ZIF-8 can reach 49.26 F/g. GAC+10% ZN-ZIF-8 achieved better performance than that with GAC electrode, which the Na+ removal efficiency increased by 7.83%, and the electrosorption capacity increased from 43.01 μmole Na+/g to 121.12 μmole Na+/g.
In the study of high temperature carbonization (400, 500, 600, 700, 800 oC) of ZIF-8, the specific capacitance value of ZIF-8_700 can reach 66.73 F/g. ZIF-8_800 had the best CDI performance and the electrosorption capacity was from 120.15 μmole Na+/g to 136.44 μmole Na+/g.
ZIF-8 has great potential in CDI system. GAC mixed with ZIF-8 in an appropriate proportion or high-temperature carbonized ZIF-8 as CDI electrode can effectively improve the removal of Na+ and Cl-.

並列關鍵字

capacitive deionization ； Zeolitic Imidazolate Framework ； ZIF-8 ； carbonization ； zinc nitrate

參考文獻

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