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The main aim of this study was determination of carbonate and zeolitic materials usefulness from
point of view application of them as carbon dioxide sorbents. To these tests carbonate resources
commonly occuring on Lublin Upland were chosen. They were the following materials: silicacarbonate
rocks (opokas) from Kazimierz Dolny area, carbonate-silica rocks (detritic sandy limestone)
from Józefów area, carbonate rocks (organodetritic limestone) from Łysaków area, chalks from Chełm
area and peelite marlstones form Rejowiec area. Besides, to examinations they were chosen synthetic
zeolites such as NaX, NaP1, that are produced as a result of hydrothermal reaction of fly ash with
NaOH water solution [1,2]. For all selected materials mineralogical examinations (XRD, SEM analysis and observation in polarised light) were conducted. Also textural characteristics (Tab. 1) were carried out. The BET surface area, mean pore diameter, pore size distribution and volume of pores for each sample were determine. An essential research has constituted CO2 adsorption test (Tab. 2) at static condition with 750 mmHg pressure, that allowed to determine usefulness of selected materials to application of them as CO2 sorbents. Mineralogical researches of carbonate rocks have shown that the dominant mineral component is calcite, acompanied by small amounts of quartz, CT opal and clay minerals depending on petrographic character of tested rocks. In zeolitic samples dominant components are zeolites types NaX and NaP1, and mullite, quartz, aluminosilicate glass are also observed. In case of textural analysis the lowest the BET surface area have chalk, carbonate-silica and
carbonate rocks (from 1.8 to 6.5 m2/g). Better values were obtained for opokas and marlstones (form
25 to 53 m2/g). Much higher values were noted for zeolitic materials (NaP1 169.8 m2/g, NaX 403.7
m2/g). Average pore diameter for all tested sapmles ranges from 64 Å for NaX to 135 Å for NaP1,
respectively. The highest values of mesopore volumes have zeolites and opokas (form 0.129 cm3/g for
Kazimierz Dolny opoka to 0.308 cm3/g for NaP1 zeolite, respectively) whereas rest of materials have
very low mesopore volumes. CO2 adsorption tests (Tab. 2) have revealed that carbonate rocks have poor adsorption properties, their sorption capacity do not exceed 0.1 mmol/g. Therefore, they should be examinated from point of view application of them in mineral carbonation, as CO2 adsorbents but only after calcining of them into CaO and after that to use them to carbon dioxide capture [3]. Hovewer zeolites International Conference on Carbon Reduction Technologies CaReTECH2011, 19-22 September 2011, Poland c Institute of Thermal Technology, 2011 94 have shown much better CO2 adsorption parameters (their sorption capacity is 0.9 mmol/g for NaX and 0.4 mmol/g for NaP1, respectively), thus, they can be subjected to further examiantions (modification/activation) in order to determine selective and dynamic adsorption of CO2 [4-6].
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