Pressure swing adsorption process for chlorine plant offgas

A pressure swing adsorption process for the recovery and removal of chlorine from a chlorine plant offgas stream comprising hydrogen, air, and chlorine, said process comprising:

• a) passing said chlorine plant offgas stream at a chlorine plant pressure to a first compressor to raise said pressure to a first condensation pressure and provide a compressed chlorine plant offgas stream;
• b) cooling and condensing said compressed chlorine plant offgas stream to provide a first liquid chlorine product stream and a first reduced chlorine offgas stream comprising hydrogen and having a concentration of chlorine which is lower than that of said chlorine plant offgas stream;
• c) passing said first reduced chlorine offgas stream to a pressure swing adsorption zone at adsorption conditions including an adsorption pressure, said pressure swing adsorption zone comprising a first adsorption bed of at least two adsorption beds each of said adsorption beds having a first adsorbent layer containing a weak adsorbent selective for the adsorption of chlorine and at least a second adsorbent layer containing a strong adsorbent selective for the adsorption of chlorine to provide a vent gas stream comprising hydrogen and a tail gas stream comprising chlorine;
• d) compressing, cooling, and condensing said tail gas stream to provide a second liquid chlorine product stream and a second reduced chlorine offgas stream;
• and,
• e) passing said second reduced chlorine offgas stream to said pressure swing adsorption zone to be admixed with said chlorine plant offgas stream.