Synthesis Of Iron Metal-Organic Coordination Polymer For Ethylene Oligomerization

Ethylene oligomerization has been dominated for ages by nonselective ones which yield a wide spectrum of linear?-olefins often following a Schulz-Flory distribution or a Poisson distribution.The light fraction of linear?-olefins(LAOs),particularly C4,C6,and C8,are employed as comonomers for the production of linear low-density polyethylene(LLDPE)copolymers.Continually increasing demand for these shortchain oligomers has led to great interest in selective ethylene oligomerization technologies.Ethylene oligomerization can also be used to produce gasoline fractions,and product gasoline can be an ideal gasoline blending component.One-dimensional,two-dimensional and three-dimensional iron-based metal organic coordination polymers(1/2/3D-Fe)were synthesized by a solvothermal method.They were heated under vacuum to obtain a series of 1/2/3D-Fe catalysts,which were then used for ethylene oligomerization.The effects of vacuum treatment temperatures,catalyst concentrations,ethylene pressure and reaction time on the catalytic activity and product selectivity of the 1/2/3D-Fe catalysts were investigated.The results showed that the ethylene oligomerization product of 1D-Fe catalyst was mainly C8 with the selectivity to C8 of 94.75%(the content of?-C8 was 19.18%),and the catalytic activity of 3.88×10~5 g/(mol?h).The products of 2D-Fe catalyst and 3D-Fe catalyst are mainly C4and C8.Under the same conditions,the activity of 2D-Fe catalyst was 3.29×10~4g/(mol?h)with the selectivity to C4 and C8 of 38.53%and 34.82%,and the activity of3D-Fe catalyst was 1.95×10~5 g/(mol?h)with the selectivity to C8 of 56.01%(the content of?-C8 was 13.26%).