Production of activated carbons from waste tyres for low temperature NOx control

• Published in: Waste management (Elmsford) Vol. 49; pp. 188 - 195
• Main Authors: Al-Rahbi, Amal S., Williams, Paul T.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.03.2016
• Subjects: Activated carbon; Adsorption; Air Pollutants - chemistry; Air Pollution - prevention & control; Carbon; Charcoal - analysis; Cold Temperature; Flue gases; Nitrogen Oxides - chemistry; NOx; Refuse Disposal - economics; Rubber; Solid Waste - analysis; Surface area; Texture; Tires; Tyre; Tyres; Waste; Waste Management - economics; Waste Management - methods; Wastes; Tyre; Waste; Activated carbon; NOx
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/j.wasman.2016.01.030

[Display omitted] •Chars from waste tyres were chemically activated to produce activated carbons.•Chemical activation used, KOH, K2CO3, NaOH and Na2CO3.•Product carbons were used to adsorb NO at low temperature (25°C).•Maximum NO removal efficiency was ∼75% with KOH.•High carbon surface area and micropore volume gave the highest NO adsorption. Waste tyres were pyrolysed in a bench scale reactor and the product chars were chemically activated with alkali chemical agents, KOH, K2CO3, NaOH and Na2CO3 to produce waste tyre derived activated carbons. The activated carbon products were then examined in terms of their ability to adsorb NOx (NO) at low temperature (25°C) from a simulated industrial process flue gas. This study investigates the influence of surface area and porosity of the carbons produced with the different alkali chemical activating agents on NO capture from the simulated flue gas. The influence of varying the chemical activation conditions on the porous texture and corresponding NO removal from the flue gas was studied. The activated carbon sorbents were characterized in relation to BET surface area, micropore and mesopore volumes and chemical composition. The highest NO removal efficiency for the waste tyre derived activated carbons was ∼75% which was obtained with the adsorbent treated with KOH which correlated with both the highest BET surface area and largest micropore volume. In contrast, the waste tyre derived activated carbons prepared using K2CO3, NaOH and Na2CO3 alkali activating agents appeared to have little influence on NO removal from the flue gases. The results suggest problematic waste tyres, have the potential to be converted to activated carbons with NOx removal efficiency comparable with conventionally produced carbons.