Continuous manufacturing process for alpha-olefins
AssigneeE. I. Du Pont de Nemours and Company
InventorRinaldo S. Schiffino
Life of this patent
Estimating the term…
Abstract
A manufacturing process for α-olefins using certain iron containing ethylene oligomerization catalysts together with alkylaluminum cocatalysts, in which using a low ratio of Al:Fe in the process results in a lowered formation of undesired polyethylene waxes and polymer. This results in less fouling of the process lines and vessels in the manufacturing plant.
Claims12
A continuous process for the production of a linear α-olefin product, comprising the step of contacting, in a continuous reactor, process ingredients comprising an ethylene oligomerization catalyst composition, ethylene and a co-catalyst, wherein:
- (a) the ethylene oligomerization catalyst composition comprises an iron complex of a compound of the formula
- wherein:
- R1, R2 and R3 are each independently hydrogen, hydrocarbyl, substituted hydrocarbyl or an inert functional group, provided that any two of R1, R2 and R3 vicinal to one another taken together may form a ring;
- R4 and R5 are each independently hydrogen, hydrocarbyl, substituted hydrocarbyl or an inert functional group;
- R6 and R7 are each independently a substituted aryl having a first ring atom bound to the imino nitrogen, provided that:
- in R6, a second ring atom adjacent to said first ring atom is bound to a halogen, a primary carbon group, a secondary carbon group or a tertiary carbon group;
- and further provided that
- in R6, when said second ring atom is bound to a halogen or a primary carbon group, none, one or two of the other ring atoms in R6 and R7 adjacent to said first ring atom are bound to a halogen or a primary carbon group, with the remainder of the ring atoms adjacent to said first ring atom being bound to a hydrogen atom;
- or
- in R6, when said second ring atom is bound to a secondary carbon group, none, one or two of the other ring atoms in R6 and R7 adjacent to said first ring atom are bound to a halogen, a primary carbon group or a secondary carbon group, with the remainder of the ring atoms adjacent to said first ring atom being bound to a hydrogen atom;
- or
- in R6, when said second ring atom is bound to a tertiary carbon group, none or one of the other ring atoms in R6 and R7 adjacent to said first ring atom are bound to a tertiary carbon group, with the remainder of the ring atoms adjacent to said first ring atom being bound to a hydrogen atom;
- (b) the cocatalyst comprises an alkyl aluminum compound;
- and
- (c) the molar ratio of Al in the cocatalyst to Fe in the ethylene oligomerization catalyst is about 2000 or less.
An improved continuous process for the production of a linear α-olefin product, the production process comprising the step of contacting, in a continuous reactor, process ingredients comprising an ethylene oligomerization catalyst composition, ethylene and a cocatalyst, wherein:
- (a) the ethylene oligomerization catalyst composition comprises an iron complex of a compound of the formula
- wherein:
- R1, R2 and R3 are each independently hydrogen, hydrocarbyl, substituted hydrocarbyl or an inert functional group, provided that any two of R1, R2 and R3 vicinal to one another taken together may form a ring;
- R4 and R5 are each independently hydrogen, hydrocarbyl, substituted hydrocarbyl or an inert functional group;
- R6 and R7 are each independently a substituted aryl having a first ring atom bound to the imino nitrogen, provided that:
- in R6, a second ring atom adjacent to said first ring atom is bound to a halogen, a primary carbon group, a secondary carbon group or a tertiary carbon group;
- and further provided that
- in R6, when said second ring atom is bound to a halogen or a primary carbon group, none, one or two of the other ring atoms in R6 and R7 adjacent to said first ring atom are bound to a halogen or a primary carbon group, with the remainder of the ring atoms adjacent to said first ring atom being bound to a hydrogen atom;
- or
- in R6, when said second ring atom is bound to a secondary carbon group, none, one or two of the other ring atoms in R6 and R7 adjacent to said first ring atom are bound to a halogen, a primary carbon group or a secondary carbon group, with the remainder of the ring atoms adjacent to said first ring atom being bound to a hydrogen atom;
- or
- in R6, when said second ring atom is bound to a tertiary carbon group, none or one of the other ring atoms in R6 and R7 adjacent to said first ring atom are bound to a tertiary carbon group, with the remainder of the ring atoms adjacent to said first ring atom being bound to a hydrogen atom;
- and
- (b) the cocatalyst comprises an alkyl aluminum compound;
- wherein the improvement comprises reducing the formation of polyethylene waxes and polymers in the linear α-olefin product by contacting the process ingredients at a molar ratio of Al in the cocatalyst to Fe in the ethylene oligomerization catalyst of about 2000 or less.
Dependencies are inferred from the claim text.