무기성 상전이 물질의 활성탄 세공 내 담지 기술 개발

국문 초록 (Abstract)

목적: 최근 에너지 관련 연구는 대체에너지 개발에서 나아가, 생산된 에너지의 효율적 관리 기술 개발로 변화하고 있다. 이에 대해 에너지 저장 및 방출 기능을 가진 상전이 물질을 에너지 매체로 사용하는 연구가 꾸준히 진행되고 있다. 본 연구에서는 활성탄을 상전이 물질의 충진매체로 사용하여 보다 효율적인 열저장매체를 개발하고자 하며 동시에 활성탄 세공 내에 상전이 물질을 효율적으로 충진시키는 방법을 개발하고자 한다.
방법: 본 실험에 사용한 활성탄은 목탄계 분말 활성탄(250-350 mesh)과 입상활성탄을 이용하였으며 실험에 사용한 무기성 상전이 물질로는 Manganese nitrate hexahydrate을 사용하였다. 상전이 물질의 세공내 충진 방법은 가압방식과 희석방식을 이용하였으며 개발 소재의 열 흡수/방출 능력은 10-50℃ 범위 내의 온도에서 관찰하였다.
결과 및 토의: 가압식 및 희석식 충진 방법에 따른 상전이 물질의 활성탄 충진 여부는 SEM, TEM-EDX 및 bulk density 분석을 통해 확인하였다. 가압식 방법으로 상전이 물질을 충진 하였을 경우 Manganese nitrate hexahydrate의 물질 특성이 그대로 반영되어 각각의 상전이 온도에서 열의 흡수와 방출이 발생되어 온도변화가 지연되는 구간을 보였다. 희석 방식을 이용한 상전이 물질 충진연구에서 최적 용매 선정 실험결과 에탄올을 용매로 사용하였을 경우 상전이 물질 담지 후에도 열 흡수/방출이 뚜렷하게 관찰되었다. 최적 희석 배율 선정 실험을 통해 부유하는 활성탄이 가장 최소량에 되게 하면서 에탄올의 비율이 낮은 희석 비(1:1)를 도출하였다. 용매 제거 실험결과 85℃ 온도에서 기화하여 에탄올을 제거하였을 때의 조건이 최적으로 나타났으며, 온도변화에 따른 열 흡수/방출 특성을 평가한 결과 열 흡수/방출 현상이 관찰됨을 확인하였다.
결론: 1) 가압방식 및 희석방식 모두 무기성 상전이 물질이 활성탄 내부에 고정시킬 수 있는 상전이 충진 방식이며 담지 이후에도 열 흡수/방출 특성이 유지된다.
2) 희석방식 사용 시, 에탄올이 용매로써 적합하며 최적 희석비율은 1:1임을 확인하였다.
3) 희석용매 제거 방법에 있어 기화방식이 가장 적합함을 확인하였다.

다국어 초록 (Multilingual Abstract)

Objectives : Recently, energy-related research has shifted from developing alternative energy to the efficient management technology of the produced energy. As an alternative, research on phase change materials (PCMs) capable of absorbing and releasing heat as an energy medium has been conducted. This study developed a more efficient heat storage medium using activated carbon as a medium for the phase change material. At the same time, we developed a method for efficiently impregnating the phase change material into the activated carbon pores.
Methods : The activated carbon used in this experiment was charcoal powder activated carbon (250-350 mesh) and granular activated carbon. The inorganic phase change materials used in the experiment was manganese nitrate hexahydrate. The method for impregnating the phase change material was pressurization method and dilution method. The heat absorption / emission capacity of the developed material was examined within the range of 10℃ to 50℃.
Results and Discussion : The Scanning electron microscope (SEM) and Transmission electron microscopy energy-dispersive X-ray spectroscopy (TEM-EDX) analysis showed that the phase change material was filled in the pore of activated carbon. When the phase change material is filled by the pressurized method, the material properties of manganese nitrate hexahydrate are reflected, resulting in absorption and release of heat at each phase change temperature. As a result of experiments for the selection of the optimum solvent in the phase change material filling study using the dilution method, when ethanol was used as the solvent, the heat absorption was clearly observed even after the phase change material was loaded. As a result of selecting the optimal dilution ratio, the ratio of ethanol was determined to be 1:1 as the dilution ratio with the lowest amount of floating activated carbon. The optimal solvent removal method experimental results show that the heat absorption/release section occurred when the ethanol was removed by evaporation at 85℃ temperature.
Conclusions : 1) Both the pressurization method and the dilution method are filling methods in which inorganic phase change materials can be immobilized inside activated carbon, and heat absorption and release characteristics are maintained even after loading.
2) The heat absorption release was maintained for ethanol and the optimal dilution ratio was 1:1.
3) In case of the dilute solvent removal method, the heat absorption/release capacity was maintained when the solvent was removed using only the vaporization method.

목차 (Table of Contents)

• 1. 서론
• 2. 실험방법
• 3. 결과 및 고찰
• 4. 결론
• References

참고문헌 (Reference)

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