Surface modification of activated carbons for CO2 capture

Abstract

The reduction of anthropogenic CO 2 emissions to address the consequences of climate change is a matter of concern for all developed countries. In the short term, one of the most viable options for reducing carbon emissions is to capture and store CO 2 at large stationary sources. Adsorption with solid sorbents is one of the most promising options. In this work, two series of materials were prepared from two commercial activated carbons, C and R, by heat treatment with gaseous ammonia at temperatures in the 200-800 ºC range. The aim was to improve the selectivity and capacity of the sorbents to capture CO 2 , by introducing basic nitrogen functionalities into the carbons. The sorbents were characterised in terms of texture and chemical composition. Their surface chemistry was studied through temperature programmed desorption tests and X-ray photoelectron spectroscopy. The capture performance of the carbons was evaluated by using a thermogravimetric analyser to record mass uptakes by the samples when exposed to a CO 2 atmosphere.

Sustainable biomass-based carbon adsorbents for post-combustion CO2 capture

“…The CO 2 uptake capacities at 25 ˚C and 100 ˚C, evaluated in the thermogravimetric analyser, shown in Table 3, are also in good agreement with those of Tables 1 and 2. These CO 2 uptakes are higher than those of commercial activated carbons evaluated in similar conditions [32].…”

Post-combustion CO2 capture with a commercial activated carbon: Comparison of different regeneration strategies

“…Further testing will be performed to optimise the three different regeneration strategies discussed herein (TSA, VSA and VTSA); likewise, a cost estimation of the involved regeneration energy for each strategy is needed to reallistically compare the CO 2 capture potential of the activated carbon presented here with current state-of-the-art CO 2 capture technologies. 942 [27] Helium density (kg m -3 ) 2136…”

“…It will be denoted from now on as R. A detailed textural characterisation of R can be found elsewhere [27].…”

“…Besides a suitable textural development, particular attention has been paid to the incorporation of basic nitrogen functionalities to enhance the affinity of the adsorbents towards CO 2 [25][26][27][28][29][30].…”

Influence of oxidation upon the CO2 capture performance of a phenolic-resin-derived carbon

“…It is well established that the electron-deficient carbon atom of CO 2 can act as a Lewis acid and participate in stabilizing reactions with Lewis base groups such as amines [21]. As a result, research has focussed on the incorporation of nitrogen functionalities onto the surface of activated carbons to promote their performance as adsorbents in CO 2 capture applications [22][23][24][25][26]. However, nitrogen functionalities are not the only species capable of acting as Lewis bases.…”