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Modification of CaCO3 and CaCO3 pin-coated cellulose paper under supercritical carbon dioxide–ethanol mixture for enhanced NO2 capture.
- Source :
- Environmental Science & Pollution Research; Feb2022, Vol. 29 Issue 8, p11707-11717, 11p
- Publication Year :
- 2022
-
Abstract
- In this work, we examine two modifications of fine-ground calcium carbonate material (GCC) in order to enhanced sorption of NO<subscript>2</subscript> and subsequent reaction properties toward NO<subscript>2</subscript><superscript>−</superscript>/NO<subscript>3</subscript><superscript>−</superscript> formation by firstly exposing the GCC to supercritical (sc) CO<subscript>2</subscript> in order to increase particle surface area, a choice specifically made to avoid altering the surface chemistry, and secondly considering the potential advantage of using a surface coupling agent toward NO<subscript>2</subscript>. The modification by the coupling agent amino silane (AMEO silane) was applied in a supercritical CO<subscript>2</subscript>–ethanol mixture. The samples were characterised before and after modification by field emission scanning electron microscopy (FESEM), specific surface area determination (BET nitrogen adsorption), ATR-FTIR spectroscopy and ion chromatography to reveal the effects of the surface modification(s) on the morphology, surface textural properties and sorption versus reaction properties with NO<subscript>2</subscript>. The performance of the treated sorbents for NO<subscript>2</subscript> capture was evaluated at room temperature. Results show that reactivity of NO<subscript>2</subscript> with GCC was observed to increase as a function of increased surface area resulting from scCO<subscript>2</subscript> exposure, but that the presence of AMEO silane on the surface, while enhancing initial adsorption of NO<subscript>2</subscript> was seen subsequently to act to block reactivity. Thus, judicious use of coupling agent can provide desired rapid initial adsorption of the gas, but the goal of long-term CaCO<subscript>3</subscript>-consuming reactivity, so as to prolong the uptake of NO<subscript>2</subscript> beyond surface saturation alone, is achieved by increasing surface area while retaining chemical-free exposed CaCO<subscript>3</subscript> surface. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 09441344
- Volume :
- 29
- Issue :
- 8
- Database :
- Complementary Index
- Journal :
- Environmental Science & Pollution Research
- Publication Type :
- Academic Journal
- Accession number :
- 154921559
- Full Text :
- https://doi.org/10.1007/s11356-021-16503-9