EFFECT OF TITANIUM CONTENT ON ZIEGLER-NATTA CATALYST PERFORMANCE

In this study, the effect of titanium content through using Lewis acid in the removal of Lewis base (EtOH and THF) in MgCl2 structure was investigated. The catalytic activity of synthesized catalysts was tested in ethylene polymerization. For MgCl2/EtOH system, the type of Lewis acid such as alkylaluminum chloride (DEAC, EADC and its mixture) was used. It was found that titanium content was increased with an increase of DEAC/MgCl2 molar ratio. However, the suitable molar ratio of MgCl2/DEAC exhibited the highest catalytic activity. In comparison between the use of DEAC and EADC, it was found that using of DEAC showed higher catalytic activity than the use of EADC. In addition, the suitable molar ratio of DEAC/EADC mixture also showed the high catalytic activity. The removal of ethanol using alkylaluminum chloride caused an increase in surface area and a decrease in the crystallinity of MgCl2. This led to the suitable interaction of TiCl4 and MgCl2. For MgCl2/THF system, the type of Lewis acid such as metal chloride (AlCl3, CaCl2, FeCl2 and ZnCl2) was selected. The results showed that the modification of AlCl3 + FeCl2 provided the highest activity because it had an efficiency to remove higher amount of THF, which can be confirmed by XRD and FT-IR. However, the titanium content was not increased by the removal of THF.