利用碳氣凝膠紙對硝酸根離子進行電容去離子之研究

The removal of nitrate via the capacitive deionization using carbon aerogel electrodes

李岳青(Yueh-Ching Li)

指導教授 ： 秦靜如

國立中央大學/工學院/環境工程研究所/碩士(2015年)

摘要

水資源問題在最近幾年已經漸漸的受到世界各地的關注，其中在人類生活會影響到的水質問題中，水中含氮物質像是硝酸根離子、亞硝酸根離子、氨氮等物質的減量或去除也將會是個重要的課題；本研究是透過以碳氣凝膠紙當作電極，並利用電容去離子機制去除硝酸根離子，並透過不同外加電壓以及不同的初始硝酸根離子濃度，瞭解外加電壓與離子濃度對碳氣凝膠紙的電容去離子系統有何影響。結果顯示，當初始硝酸根離子濃度為100 ppm且外加電壓從0.8 V上升到1.2 V時，硝酸根離子的電容去離子量（電容吸附和還原與脫附量的總合）從2.30 mg/g上升到5.18 mg/g，這是來自電容吸附量隨電壓提高而提高（0.43 mg/g上升到4.58 mg/g），而硝酸根離子還原與脫附量則沒有明顯變化。當初始硝酸根離子濃度從10 ppm提高到200 ppm且外加電壓為1.1 V或1.2 V時，電容吸附量從1.34 mg/g上升到4.48 mg/g，但當初始硝酸根離子濃度提高為500 ppm時，電容吸附量僅剩下2.62 mg/g。以本系統而言，在低初始濃度（10 ppm）時，去除硝酸根離子的效率可達50.53%。本系統的碳氣凝膠紙經過四次反覆充放電後，第四次的電容吸附量還能有第一次的90.9%左右。

關鍵字

碳氣凝膠紙 ； 電容去離子 ； 電容吸附 ； 硝酸根離子

並列摘要

Reduction or removal of nitrate, nitrite, and ammonia in the water are important issues. This study focused on the removal of nitrate via the capacitive deionization using carbon aerogel electrodes. The influences of voltages and initial nitrate concentrations on the removal of nitrate and speciation of nitrogen are investigated. The results showed that the removal amount of nitrate increases from 2.30 mg/g to 5.18 mg/g when the applied voltage increased from 0.8 V to 1.2 V with the initial nitrate concentration of 100 ppm. These removal of nitrate may be contributed from the capacitance adsorption and the reduction of nitrate. The amount of nitrate removed by capacitance adsorption increased from 0.43 mg/g to 4.58 mg/g when the applied voltage increased from 0.8V to 1.2 V. At the meantime, the reduction and desorption nitrate did not affected by applying different voltage. The amount of nitrate removed by capacitance adsorption increased from 1.34 mg/g to 4.48 mg/g when the nitrate concentration increased from 10 ppm to 200 ppm, but decreased to 2.62 mg/g when nitrate concentration increased to 500 ppm. At low nitrate concentration (10 ppm), the removal efficiency reached 50.53%. And the capacitive adsorption ability was about 90.9% after four cycles.

並列關鍵字

Capacitance adsorption ； carbon aerogel ； CDI ； nitrate

參考文獻

鄭喬薇, "碳氣凝膠電容吸附水中重金屬", 國立中央大學環境工程研究所碩士論文, (2007).

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