Process for production of propylene and ethylbenzene from dilute ethylene streams

A process for producing propylene and an alkylaromatic, comprising:

• a) reacting a feedstock in an ethylene reaction zone to produce a first ethylene stream from thermal cracking of hydrocarbons in the presence of steam;
• b) directing the first ethylene stream to a propylene reaction zone;
• c) directing a butene stream to the propylene reaction zone;
• d) reacting the first ethylene stream with the butene stream in the propylene reaction zone to produce a propylene reaction stream;
• e) subjecting the propylene reaction stream to a first recovery operation to recover the propylene and a second ethylene stream comprising above 60 mole percent ethylene to about 90 mole percent ethylene;
• f) directing the second ethylene stream to an alkylaromatic reaction zone without recycling of any of the second ethylene stream to the propylene reaction zone;
• g) directing an aromatic stream to the alkylaromatic reaction zone;
• h) reacting the second ethylene stream with the aromatic stream in the alkylaromatic reaction zone to produce an alkylaromatic reaction stream;
• and
• i) subjecting the alkylaromatic reaction stream to a second recovery operation to recover the alkylaromatic.