질산은이 함침된 클레이 흡착제에 대해 283 K, 298 K, 313 K, 333 K에서 에탄과 에틸렌의 순수성분 흡착량을 측정하였으며 298 K와 313 K에서 이성분 흡착평형을 측정하였다. 에틸렌은 일가 은이온과 π-착합체를 형성하기 때문에 질산은이 분산되지 않은 클레이에서 보다 흡착량이 증가하였으며 에탄은 오히려 감소하였다. 에탄의 순수성분 흡착평형은 Langmuir 평형식으로도 잘 나타낼 수 있었으며 에틸렌은 Freundlich 평형식이나 물리흡착과 π-착합체 형성을 고려하는 혼성모델로 흡착 평형량을 잘 나타낼 수 있었다. 에탄과 에틸렌 모두 흡착량의 증가에 따라 흡착열의 감소를 보였으며 특히 에틸렌의 경우 흡착량이 1.2 mmol/g 이상에서는 에탄의 흡착열과 거의 비슷한 수치를 나타내었다. 이성분 평형 실험 결과 에탄은 클레이 표면에서 뿐만 아니라 질산은에도 흡착하는 것으로 나타났지만 에탄은 질산은이 분산되지 않은 클레이 표면에서 에틸렌과 경쟁흡착하고 질산은 위에는 에틸렌만이 약한 화학흡착을 한다는 가정하에서 에탄과 에틸렌의 흡착평형량을 잘 예측할 수 있었다.

Adsorption isotherms of ethane and ethylene at 283 K, 298 K, 313 K, and 333 K, and binary adsorption equilibria at 298 K and 313 K were measured on an AgNO3/clay adsorbent. Since ethylene forms π-complex with mono valent silver ion, the amount adsorbed of ethylene on AgNO3/clay adsorbent was larger than that on bare clay adsorbent while the amount adsorbed of ethane was smaller. Pure component adsorption isotherms of ethane were fairly well fitted even with the Langmuir model and those of ethylene were well fitted with the Freundlich model or a model accounting for both physisorption and chemisorption. Heats of adsorption of ethane and ethylene decreased with the increase of the amount adsorbed. Remarkably, the heat of adsorption of ethylene was similar to that of ethane above 1.2 mmol/g. Though the binary adsorption equilibria showed that ethane was adsorbed not only on the bare clay surface but also on silver nitrate, amounts adsorbed of ethylene and ethane were well predicted under the assumption that ethane and ethylene are competitively adsorbed on the bare clay surface and only ethylene is chemically adsorbed on the silver nitrate.

π-Complexation Ethane Ethylene Adsorption Equilibrium AgNO3 Impregnated Clay

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