A Comparative Study of AlCl₃ and FeCl₂-Modified TiCl₄/MgCl₂/THF Catalytic System in the Presence of Hydrogen for Ethylene Polymerization

Table 3

Catalytic activity of different doped Lewis acid catalysts in ethylene polymerization.

Catalyst	H2/C2H4 molar ratio	Activity; (kg PE/g)	Activity ratio without H2	Activity ratio with H2
None-THF	0	732	1.00	1.00
	0.08	645	—	0.88
	0.20	362	—	0.49
	0.30	313	—	0.43
Al-THF	0	854	1.17	1.00
	0.08	560	—	0.66
	0.20	279	—	0.33
	0.30	246	—	0.29
Fe-THF	0	1364	1.86	1.00
	0.08	452	—	0.33
	0.20	330	—	0.24
	0.30	375	—	0.28

Condition: polymerization was performed in 2 L autoclave, [Ti] = 0.008 mmol for all catalysts, Al/Ti molar ratio = 140, cocatalyst = TEA, polymerization time = 1 h, reaction temperature = 80°C, total pressure = 8 bars under 1 bar of nitrogen, and desired amount of H₂/C₂H₄ molar ratio = 0, 0.08, 0.20, and 0.30.