Methods for producing 1-hexene

A method of producing 1-hexene by ethylene oligomerization, the method comprising:

• flowing a first solvent system into a reactor unit that is in reaction mode, the first solvent system adapted to improve selectivity of 1-hexene in the oligomerizing of the ethylene;
• flowing ethylene into the reactor unit, the reactor unit containing a catalyst and a first portion of a second solvent system, the second solvent system being different from the first solvent system;
• contacting the ethylene with the catalyst;
• oligomerizing the ethylene to produce 1-hexene, in the reactor unit;
• flowing a reactor unit effluent from the reactor unit, the reactor unit effluent comprising the 1-hexene and the first and second solvent systems;
• optionally, switching the reactor unit from reaction mode to washing mode;
• and
• optionally flowing a second portion of the second solvent system into the reactor unit in washing mode, the second solvent system adapted to dissolve by-products in the reactor unit, the by-products comprising oligomers, polymers and waxes having 20 to 500 carbon atoms.