| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 40842 | Applied Catalysis A: General | 2012 | 4 Pages |
Specific surface area based on the BET method in N2 adsorption has historically posed poor correlation with olefin polymerization activity of heterogeneous Ziegler-Natta (ZN) catalysts. We have investigated the validity of the BET surface area for ZN catalysts based on the αS-plot method, where non-porous core–shell MgO/MgCl2/TiCl4 catalysts were used as a reference material. The αS-plots for typical industrial ZN catalysts clarified the presence of two classes of micropores and resultant difficulty to isolate a multilayer adsorption region for the BET method. The results cast doubt on the application of the BET method to evaluate the surface area of heterogeneous ZN catalysts.
Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (243 K)Download as PowerPoint slideHighlights► Validation of the BET surface area of Ziegler-Natta catalysts based on the αS-plot method. ► Non-porous core–shell MgO/MgCl2/TiCl4 catalysts were used as reference. ► Micropore filling heavily overlaps with a multilayer adsorption region for the BET analysis. ► The BET surface area is questionable for typical Ziegler-Natta catalysts.
