Hydrogen and carbon monoxide production by hydrocarbon steam reforming and pressure swing adsorption purification

摘要

The present invention is directed to a method for producing hydrogen and carbon monoxide from a feed mixture comprising hydrogen, carbon monoxide, carbon dioxide, and methane, which comprises the steps of (a) passing the feed mixture through a first pressure swing adsorption system comprising an adsorbent having a greater affinity for carbon dioxide, methane, and carbon monoxide than for hydrogen to separate hydrogen as a non-adsorbed product and carbon dioxide, methane, and carbon monoxide as an adsorbed fraction, (b) desorbing carbon monoxide, (c) desorbing carbon dioxide and methane, (d) passing the carbon monoxide to a second pressure swing adsorption system comprising an adsorbent having a greater affinity for carbon monoxide than for hydrogen, carbon dioxide, and methane to separate carbon monoxide as an adsorbed fraction and hydrogen, carbon dioxide, and methane as a non-adsorbed fraction, and (e) desorbing carbon monoxide. In a second embodiment, the invention is directed to a method which comprises the steps of (a) providing a pressure swing adsorption system having a first stage comprising an adsorbent having a greater affinity for carbon monoxide than for hydrogen, carbon dioxide, and methane, and a second stage comprising an adsorbent having a greater affinity for carbon dioxide, methane, and carbon monoxide than for hydrogen, (b) passing the feed mixture through the first stage to separate carbon monoxide as an adsorbed fraction and hydrogen, carbon dioxide, and methane as a non-adsorbed fraction, (c) passing the non-adsorbed fraction through the second stage to separate carbon dioxide and methane as an adsorbed fraction and hydrogen as a non-adsorbed pure product, (d) desorbing carbon dioxide and methane, and (e) desorbing carbon monoxide. IMAGE