Production of heavier hydrocarbons from light olefins in multistage catalytic reactors

A continuous multistage catlytic process for conversion of light olefins to distillate range hydrocarbons rich in C.sub.10 + aliphatics, comprising the steps of:

• maintaining a fluidized bed of medium pore acid zeolite catalyst particles in a primary reaction stage in a turbulent reactor bed maintained under reaction severity conditions effective to convert a primary ethene-containing olefinic feedstream by passing hot feedstock vapor upwardly through the fluidized catalyst bed at reaction severity conditions sufficient to convert ethene substantially to intermediate range olefins and aromatics in the C.sub.5 -C.sub.9 range;
• recovering primary stage effluent, including a liquid stream containing a major amount of aromatics-rich C.sub.5 + hydrocarbons;
• contacting a secondary olefinic feedstream comprising C.sub.3 -C.sub.4 olefins in a secondary catalytic reactor stage with a series of fixed catalyst bed reactors containing shape selective medium pore acid zeolite oligomerization catalyst at high pressure under distillate mode oligomerization conditions;
• mixing at least a portion of liquid primary stage effluent containing aromatic hydrocarbons with at least one hot inter-reactor stream containing partially upgraded olefins in the secondary stage, thereby quenching said inter-reactor stream;
• and
• coreacting said mixed stream containing partially upgraded olefins and intermediate primary stage hydrocarbons in at least one secondary stage reactor to provide distillate range hydrocarbon product.