Prediction of adsorption behavior of activated carbons ( Journal of Colloid and Interface Science,Volume 50, Issue 3, March 1975, Pages 538-544 )

Abstrac: A study was made of the effect of temperature on predictive equations recently developed and applied to gas adsorption by beds of activated and impregnated carbons. Adsorption parameters, obtained for the adsorbate DMMP on small gram quantities of impregnated carbon at 25°C and applied to carbon bed breakthru times, were analyzed for changes resulting from direct temperature effects on gas diffusion, adsorption—desorption equilibria, volume expansion, relative pressure, and adsorbate—adsorbent interactions. Modifications in the adsorption parameters, calculated for bed temperatures ranging between 40.3 and 46.7°C, were used in the kinetic equations to predict breakthru times for M10 gas filters, each containing 13,847 g of carbon. The predicted values compared very well with those experimentally determined, the mean deviation in breakthru time being 5.82%, without regard to sign. A general analysis of a 10°C rise in temperature, from 25 to 35°C, for the M10 gas filter under the test conditions used, showed that the breakthru time would be lowered 20.0 min, 87% of this lowering due to a reduced adsorption rate constant, 9% due to a reduced adsorption capacity, and 4% due to volume expansion effects on concentration and flowrate.

Adsorption of Carbon Dioxide on Activated Carbon ( Journal of Natural Gas Chemistry,Volume 15, Issue 3, September 2006, Pages 223-229 )

Abstract: The adsorption of CO2 on a raw activated carbon A and three modified activated carbon samples B, C, and D at temperatures ranging from 303 to 333 K and the thermodynamics of adsorption have been investigated using a vacuum adsorption apparatus in order to obtain more information about the effect of CO2 on removal of organic sulfur-containing compounds in industrial gases. The active ingredients impregnated in the carbon samples show significant influence on the adsorption for CO2 and its volumes adsorbed on modified carbon samples B, C, and D are all larger than that on the raw carbon sample A. On the other hand, the physical parameters such as surface area, pore volume, and micropore volume of carbon samples show no influence on the adsorbed amount of CO2. The Dubinin-Radushkevich (D-R) equation was the best model for fitting the adsorption data on carbon samples A and B, while the Freundlich equation was the best fit for the adsorption on carbon samples C and D. The isosteric heats of adsorption on carbon samples A, B, C, and D derived from the adsorption isotherms using the Clapeyron equation decreased slightly increasing surface loading. The heat of adsorption lay between 10.5 and 28.4 kJ/mol, with the carbon sample D having the highest value at all surface coverages that were studied. The observed entropy change associated with the adsorption for the carbon samples A, B, and C (above the surface coverage of 7 ml/g) was lower than the theoretical value for mobile adsorption. However, it was higher than the theoretical value for mobile adsorption but lower than the theoretical value for localized adsorption for carbon sample D.

Some interesting PDFs are enclosed

Prof Anoop Srivastava, can you kindly oblige me with your e-mail address. This is to enable send a paper on carbon dioxide removal by selected chemically activated carbon. I hope you will be able to look into it and critique it effectively with respect to methodology and other components.

Thanks

Sure why not, my email id is

[email protected]

Thanks so much...

Thanks Prof Anoop, the paper had been sent. Regards