活性炭素纖維 電極에 의한 중금속 이온의 電氣的 吸·脫着 特性 = (The) Electrosorption Characteristics of Heavy Metal Ions from Aqueous Solution by Activated Carbon Fiber Electrode

다국어 초록 (Multilingual Abstract)

The study on the electrosorption of cobalt ions oil an activated carbon fiber(ACF) felt electrode was performed to remove the cobalt ions from the radioactive liquid wastes resulting from chemical or electrochemical decontamination and to concentrate the cobalt ions adsorbed in the fresh solution. Cyclic voltammetry was investigated on a rotating-disk electrode(RDE) the determine the region of potentials within which only double-layer charging should occur. The application of an electric potental to the ACF felt effects its adsorption capacity for cobalt ions in an aqueous solution. The adsorption capacity decreases in anodic polarization while the amount adsorbed apparently increases cathrolic polarization. The ACF felt electrode regenerated by electrodesorption resulting from reversing the current and potential shows virgin capacity. Therefore the electrosorption on the ACF felt electrode can be used to remove the cobalt ions.
The high concentration of electrolytes increased the adsorbed and deserted amount of cobalt ions because the high concentration of electrolyte increases the conductivity of the solution and lowers the ohmic voltage drop. The adsorption percentage of cobalt ions removed from the solution was 100%, and desorption percentage from the electrode was 95% in a 0.1N NaCl electrolyte solution. However, in a 0.01N NaCl electrolyte solution the adsorption percentage was 75% and the desorption percentage was only 57% at maximum. The amount of cobalt ions desorbed was increased by using the fresh solution, because the electrolyte concentration was higher than that of the non-fresh solution, A current of -5mA/+5mA is more effective than -0.5mA/+0.5mA in adsorption and desorption, and a potential of +0.7V is more effective than a potential of +0.5V in desorption. Low intial pH increase desorption percentage, because excess H^+ ions were easily exchanged with adsorbed Co^2+ ions on the ACF felt electrode by producing a sufficient concentration of H^+ ions. Thus, the condition of lower pH was very effective in dissolving cobalt ions from the ACF felt electrode. In singular systems, Co(II) could be easily removed at all negative potentials, but adsorption of Cs(I) from the solution exhibited an adsorption percentage under 15% within the applied potential range, which adsorption of Sr(II) exhibited a significant potential dependence.
In binary systems, a Cs-Co system could be easily separated at all applied negative potentiasl, while a Co-Sr system could be separated at less negative potential. A Sr-Cs system could be separated at more negative potential. In ternary system, a Co-Sr-Cs system could only be separated at 0V, in which removal differences of individual components were very high.
The electrosorption process using an ACF felt electrode was confirmed to be effective in the removal of Co(II), and an ACF felt electrode could be continuously used in the purification of liquid waste.
The selective separation of Co(II), Sr(II), Cs(II) in binary, ternary systems could be obtained.
The electrosorption process as a new technology without producing secondary wastes, appears to be a promising separation technique in liquid waste treatment.

목차 (Table of Contents)

• 목차
• I. 서론 = 1
• II. 이론적 배경 = 13
• 2.1 전기흡착 = 13
• 2.1.1 흡착 = 13
• 2.1.2 흡착평형 = 14
• 2.1.3 전기적 흡,탈착 = 18
• 2.2 전기화학측정법 = 26
• 2.2.1 전기이중충 = 26
• 2.2.2 기준전극 = 33
• 2.2.3 작업전극 = 37
• 2.2.4 순환전압전류법 = 47
• 2.2.5 다공성 전극이론 = 55
• III. 실험 = 58
• 3.1 실험 재료 = 58
• 3.1.1 흡착제 = 58
• 3.1.2 활성탄소섬유전극 = 58
• 3.1.3 시약 = 59
• 3.2 실험 및 특성분석 = 59
• 3.2.1 활성탄소섬유 전극의 특성 = 59
• 3.2.2 전기흡,탈착 = 62
• IV. 결과 및 고찰 = 66
• 4.1 활성탄소섬유의 구조적,화학적 특성 = 66
• 4.1.1 활성탄소섬유의 구조적 특성 = 66
• 4.1.2 활성탄소섬유의 화학적 특성 = 68
• 4.2 순환전압전류법(대류전압전류법) = 71
• 4.3 전기 흡,탈착 = 80
• 4.3.1 회분식 전기흡착 거동 = 80
• 4.3.2 탈착거동 및 전극재생 특성 = 85
• 4.3.3 흡,탈착공정의 특성 = 93
• 4.4 전기흡착 분리기술 = 109
• V. 결론 = 116
• REFERENCES = 119
• APPENDIX = 128
• ABSTRACT = 140