455248 Development of Activated Carbons for Adsorption Heat Pumps
In this study, ACs having different content of surface functionalities but similar pore structure or similar content of surface functionalities but different pore structure were prepared by heat treatments in H2 and/or careful adjustments of carbonization and KOH activation conditions. Then, the ethanol adsorption performances of the prepared ACs were investigated by using a gravimetric adsorption apparatus.
It was found that abundant surface functionalities decreased the adsorption amount of ethanol and shortened the apparent adsorption equilibrium time due to the diffusional hindrance of ethanol molecules by strong interaction between the surface functional groups and ethanol molecules. On the other hand, as was predicted by our GCMC simulation, the AC having micropores of 1.6 nm in pore width was found to show the highest effective adsorption amount in the AHP operation range (P/P0 = 0.1-0.3), which reached to 1.7 times higher than ultrahigh surface area commercial AC, Maxsorb III. Furthermore, the superior ethanol adsorbability of the prepared AC was maintained upon adsorption/desorption cycling without remarkable pore structural and morphological degradations at least up to 10 cycles.
We believe that the findings confirmed a potential of the AC-ethanol pair for AHPs.
See more of this Group/Topical: Separations Division