Ethylene production by steam cracking of normal paraffins

A hydrocarbon conversion process for producing ethylene which process comprises:

• (a) passing a process feed stream comprising C5 to C11 hydrocarbons including C5 to C11 normal paraffins and C5 to C11 non-normal paraffins into an adsorption zone of a simulated moving bed adsorptive separation zone operated at adsorption conditions, and selectively retaining normal paraffins on a quantity of a selective adsorbent located in the adsorption zone to yield a raffinate stream comprising non-normal C5 to C11 hydrocarbons and C12 hydrocarbon desorbent;
• (b) passing C12 hydrocarbon desorbent into a desorption zone, operated at desorption conditions, of the adsorptive separation zone as at least part of a desorbent stream, and removing normal paraffins from adsorbent present in the desorption zone to yield an extract stream comprising C5 to C11 normal paraffins and desorbent;
• (c) separating the extract stream in an extract fractionation zone into a second process stream comprising desorbent and a third process stream comprising C5 to C11 non-normal paraffins;
• and
• (d) passing at least a portion of the third stream into a cracking zone and producing ethylene.

A process for preparing the feedstreams to a catalytic reforming zone and to a steam cracking unit producing ethylene, which process comprises:

• (a) passing a process feed stream comprising C5 to C9 hydrocarbons including C5 to C9 normal paraffins into a simulated moving bed adsorption zone of an adsorptive separation zone operated at an A/Fn from about 0.90 to 0.92 and selectively retaining normal paraffins on an adsorbent located in the adsorption zone to yield a raffinate stream comprising C5 to C9 non-normal hydrocarbons;
• (b) passing desorbent selected from the group C12 hydrocarbons into a desorption zone in the adsorptive separation zone as at least part of a desorbent stream and removing normal paraffins from adsorbent present in the desorption zone to yield an extract stream comprising C5 to C9 normal paraffins and desorbent;
• (c) separating the extract stream in a extract fractionation zone into a second process stream comprising desorbent and a third process stream comprising C5 to C9 normal paraffins;
• (d) passing the third process stream into a cracking zone and producing ethylene;
• (e) separating at least a portion of the raffinate stream in a raffinate fractionation zone into a fourth process stream comprising desorbent and a fifth process stream comprising C5 to C9 non-normal hydrocarbons;
• and
• (f) passing the fifth process stream into a catalytic reforming zone operated at reforming conditions.