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Conflict of Interest: In relation to this article, we declare that there is no conflict of interest.

Publication history: Received January 22, 2002
Accepted April 15, 2002

This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/bync/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Adsorptive Ethylene Recovery from LDPE Off-Gas

Soonhaeng Cho Sangsup Han^† Jongnam Kim Jongho Park Hyunku Rhee¹

Separation Process Research Center (SPRC), Korea Institute of Energy Research (KIER), 71-2, Jang-Dong, Yusong-Gu, Daejeon 305-343, Korea ¹School of Chem. Eng., Seoul National Univ., San 56-1, Shilim-Dong, Kwanak-Gu, Seoul 151-742, Korea

sshan@kier.re.kr

Korean Journal of Chemical Engineering, September 2002, 19(5), 821-826(6), 10.1007/BF02706975

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Abstract

The objective of this study was to verify experimentally the recovery of high-purity ethylene from LDPE off-gas by a vacuum swing adsorption process. Adsorbent for this purpose was prepared by the impregnation of AgNO3 on Montmorillonite clay. The prepared adsorbent with an original substrate-shaped form shows high adsorption selectivities of light olefins to the corresponding paraffins. A 4-bed vacuum swing adsorption process using the above adsorbent, in which steps comprise adsorption (feeding), cocurrent rinse with ethylene product, countercurrent desorption_x000D_ (production) of ethylene by vacuum pump, pressurization-1 with paraffin stream, pressurization-2 with the rinse off-gas from the other bed and pressurization-3 with paraffin stream, was experimentally applied to recover ethylene from LDPE off-gas. Ethylene product purity of 99.95% could be obtained with the recovery of over 93%. The ethylene productivity of prepared adsorbent was 1.98 mol/kg·hr.

Keywords

π-Complexation Ethylene Olefin Selective Adsorbent LDPE Off-gas Vacuum Swing Adsorption Process

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