A process for producing propylene is provided which includes directing an ethylene stream from an ethylene reaction zone to a propylene reaction zone; directing a butene stream to the propylene reaction zone; reacting the ethylene stream with the butene stream in the propylene reaction zone to produce a propylene reaction stream; and subjecting the propylene reaction stream to a recovery operation to recover propylene. A processes is also provided for producing an alkylaromatic by directing an ethylene stream from a propylene reaction zone to an alkylaromatic reaction zone; directing an aromatic stream to the alkylaromatic reaction zone; reacting the ethylene stream with the aromatic stream in the alkylaromatic reaction zone to produce an alkylaromatic reaction stream; and subjecting the alkylaromatic reaction stream to a recovery operation to recover alkylaromatics. A process for producing propylene and an alkylaromatic is also provided.