Ag-based π-complexation adsorbent for paraffin/olefin separation

With the massive requisition of light olefins in dedicated areas of petrochemical industry, adsorption separation approaches are developed to meet the requirements. The literature studying long-chain olefins/alkanes is scarce, and the actual adsorption capacity of liquid-phase is rarely studied. In this paper, the adsorption process of Ag-10× zeolite for long-chain alkanes/olefins was systematically studied, the preparation conditions and operating conditions of the zeolite were investigated. The samples were characterized by XRD, BET and XPS. The results show that silver ions were uniformly dispersed on the surface of the zeolite. The actual adsorption capacity of the modified zeolite was determined in intermittent experiments by liquid phase concentration difference and pore volume correction. The experimental data were fitted and the results showed that the Langmuir isotherm equation was more appropriate for adsorption, indicating that the adsorbent surface was homogeneous. The quasi-secondary kinetic chemical equation was consistent with the adsorption of olefins by the modified 10× zeolite, indicating that the process was a chemisorption process. Experimental results shows that Ag-10× zeolite is an excellent adsorbent for separating long-chain olefins/alkanes mixed systems.