Preparation of carbon dioxide adsorbents from the chemical activation of urea–formaldehyde and melamine–formaldehyde resins

Adsorption is considered to be one of the more promising technologies for the capture of CO2 from flue gases. In general, nitrogen enrichment is reported to be effective in enhancing the specific adsorbent–adsorbate interaction for CO2. Nitrogen enriched carbons were produced from urea–formaldehyde and melamine–formaldehyde resins polymerised in the presence of K2CO3 as a chemical activation agent, with activation undertaken over a range of temperatures. CO2 adsorption capacity was determined to be dependent upon both textural properties and more importantly nitrogen functionality. Adsorbents capable of capturing above 8 wt.% CO2 at 25 °C were produced from the chemical activation of urea–formaldehyde resin at 500 °C. Chemical activation seems to produce more effective adsorbents than CO2 activation.