Crucial role of alkali metal ions and Si/Al ratio in selective adsorption of 1-octene using faujasite zeolites
- Authors
- Park, Hui Seon; Cho, Dong-Woo; Kim, Kwangsoo; Kim, Byung-Hyun; Park, Jongkee; Yoo, Chung-Yul; Jung, Taesung
- Issue Date
- Jun-2023
- Publisher
- Pergamon Press Ltd.
- Keywords
- Adsorptive separation; Alkali metal ions; Ion exchange; Linear alpha-olefin; Low-silica zeolites
- Citation
- Separation and Purification Technology, v.314, pp 1 - 13
- Pages
- 13
- Indexed
- SCIE
SCOPUS
- Journal Title
- Separation and Purification Technology
- Volume
- 314
- Start Page
- 1
- End Page
- 13
- URI
- https://scholarworks.bwise.kr/erica/handle/2021.sw.erica/115228
- DOI
- 10.1016/j.seppur.2023.123531
- ISSN
- 1383-5866
1873-3794
- Abstract
- Linear α-olefins (LAOs) are conventionally purified from paraffins via energy-intensive superfractionation. Adsorptive separation with zeolite-based adsorbents is a promising alternative to distillation for olefin/paraffin purification. However, very few zeolites with different Si/Al ratios and metal ion types have been tested to separate LAOs in the liquid phase. In this study, we investigated the ability of various alkali metal ion-exchanged faujasites with different Si/Al ratios to separate 1-octene/n-octane mixtures. We prepared low-silica X (LSX), X, and Y zeolites loaded with Li+, Na+, K+, and Rb+ via ion exchange in an aqueous solution. The 1-octene adsorption capacities and selectivities were analyzed via liquid-phase batch adsorption experiments. Among LSX, X, and Y exchanged with the Na+ and Li+, LSX which had the lowest Si/Al ratios exhibited the highest selectivity. The 1-octene selectivities for LSX were in the following order: Rb+ ≈ K+ < Na+ < Li+. LiLSX demonstrated the greatest separation efficiency among the zeolites owing to the presence of the largest number of cation sites and the highest charge density of Li+. The affinity constants calculated from the Langmuir-type adsorption isotherms and enthalpies of adsorption suggest that cation–π interactions between the C = C bond in olefins and metal ions influence selective adsorption. Density functional theory calculations support this theory of intermolecular interactions. Furthermore, a series of adsorption and desorption breakthrough experiments using a column packed with LiLSX validated its applicability for separating 1-octene and n-octane. We believe these adsorbents can be modified further and widely applied in the purification of higher olefins from chemical and biochemical products. © 2023 Elsevier B.V.
- Files in This Item
-
Go to Link
- Appears in
Collections - COLLEGE OF SCIENCE AND CONVERGENCE TECHNOLOGY > DEPARTMENT OF CHEMICAL AND MOLECULAR ENGINEERING > 1. Journal Articles
![qrcode](https://api.qrserver.com/v1/create-qr-code/?size=55x55&data=https://scholarworks.bwise.kr/erica/handle/2021.sw.erica/115228)
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.