Microporous carbon materials with extremely small pore size are prepared by employing polyaniline as a carbon precursor and KOH as an activating agent. CO(2) sorption performance of the materials is systematically investigated at the temperatures of 0, 25 and 75 °C. The prepared carbons show very high CO(2) uptake of up to 1.86 and 1.39 mmol g(-1) under 1 bar, 75 °C and 0.15 bar, 25 °C, respectively. These values are amongst the highest CO(2) capture amounts of the known carbon materials. The relation between CO(2) uptake and pore size at different temperatures is studied. An interesting and innovative point that the micropores with pore size smaller than a critical value play a crucial role in CO(2) adsorption at different temperatures is demonstrated. It is found that the higher the sorption temperature is, the smaller this critical value of pore size is. Pores smaller than 0.54 nm are manifested to determine CO(2) capture capacity at high sorption temperature, e.g. 75 °C. This research proposes a basic principle for designing highly efficient CO(2) carbon adsorbents; that is, the adsorbents should be primarily rich in extremely small micropores.

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In this study, we have explored for the first time the use of the mesoporous KIT-6 silica as an additive to enhance the gas permeability and separation characteristics of PVDF supported polydimethylsiloxane (PDMS) with filler loadings varying between 0 and 25 wt%. The KIT-6 silica was synthesized by a templating method and functionalized through silanization confirmed via Fourier transform infrared spectroscopy. The SEM images of the MMMs suggested that p-KIT-6 silica particles could embed well into the PDMS matrix and the MMMs could be defect free. With an optimum loading of 2 wt%, the C 4 H 10 permeability and C 4 H 10 /N 2 ideal selectivity of the MMM were shown to increase by 464% and 248% compared with the neat polymer membrane, respectively. In addition, the optimum membrane was also evaluated for CO 2 /N 2 separation, which proved that the permeability and selectivity increasedsimultaneously. An interface morphology has also been proposed to explain the separation phenomenon of the MMM reasonably. Taken all together, it is expected that the mesoporous KIT-6 silica would be an attractive additive to enhance the gas separation performances of polymer membranes.