ORALS
SESSION: MoltenMonPM1-R3
| Fehrmann International Symposium on Sustainable Molten Salt and Ionic Liquid Processing (6th Intl. Symp. on Sustainable Molten Salt and Ionic Liquid Processing) |
Mon Nov, 5 2018 / Room: Bossa (150/3rd) | |
Session Chairs: Peter Wasserscheid; Session Monitor: TBA |
14:50: [MoltenMonPM107]
Switchable Aqueous Pentaethylenehexamine for CO<sub>2</sub> Capture Santosh
Khokarale1 ;
Jyri-pekka
Mikkola2 ;
1Chemistry Department, Umeå University, Umeå, Sweden;
2Abo Akademi University, Turku, Finland;
Paper Id: 180
[Abstract] Carbon dioxide (CO<sub>2</sub>) concentration in the atmosphere surpassed the 400 ppm milestone in 2016 [1], approximately 120 ppm higher compared to the pre-industrial era. Along with the significant increase in the CO<sub>2</sub> level during the past decades, the human race has witnessed unprecedented climate change [2]. Therefore, it is necessary to find an efficient solution for capturing CO<sub>2</sub> from flue gases, in order to cut down anthropogenic CO<sub>2</sub> emissions. There is an increasing interest in polyamines, because they possess multiple reactive sites for high CO<sub>2</sub> uptake capacity, high thermal stability, as well as lower toxicity compared to the today's alternatives. Polyamines have the potential to improve the CO<sub>2</sub> loading, CO<sub>2</sub> absorption rate, and has a lower energy penalty [3, 4]. <br /> A reversible CO<sub>2</sub> uptake study was performed in neat pentaethylenehexamine (PEHA) and its aqueous solutions, and the performance was compared with industrially applied aqueous solution of monoethanolamine (MEA). Simultaneously, the relative amount of CO<sub>2</sub> chemisorbed chemical species, such as carbamates/(bi)-carbonates forming, was studied using NMR analysis and a calculation method introduced by Holmes et al. [5]. Furthermore, the CO<sub>2</sub> capture capacity of the solvents, correlated with their respective Kamlet-Taft polarity parameters, and the system were modelled with Linear Solvation Energy Relationship (LSER) approach. <br />It was observed that CO<sub>2</sub> capture capacity, as well as the nature of chemical species were influenced by water. The LSER calculations represented that amongst the studied Kamlet-Taft parameters, the CO<sub>2</sub> capture capacity merely depends on hydrogen bond acceptor ability (beta) and polarizability (pi). Upon the thermal regeneration study, the pure PEHA was obtained from CO<sub>2</sub> saturated reaction mixture at 120°C. Considering the high CO<sub>2</sub> absorption capacity and very low evaporation rate during regeneration compared to aqueous solution of MEA, PEHA can be used as a sustainable solvent for CO<sub>2</sub> capture in large-scale flue gas cleaning processes.
References:
[1] E. Dlugokencky, P. Tans, NOAA/ESRL (www.esrl.noaa.gov/gmd/ccgg/trends/).
[2] R. A. Kerr, Science 316 (2007), 188-190
[3] Y. E. Kim, S. J. Moon, Y. I. Yoon, S. K. Jeong, K. T. Park, S. T. Bae, S. C. Nam, Separation and Purification Technology 122 (2014) 112-118
[4] P. Muchan, J. Narku-Tetteh, C. Saiwan, R. Idem, T. Supap, Separation and Purification Technology 184 (2017) 128-134
[5] P. E. Holmes II, M. Naaz, B. E. Poling, Ind. Eng. Chem. Res. 37 (1998) 3281-3287
SESSION: MoltenTuePM2-R3
| Fehrmann International Symposium on Sustainable Molten Salt and Ionic Liquid Processing (6th Intl. Symp. on Sustainable Molten Salt and Ionic Liquid Processing) |
Tue Nov, 6 2018 / Room: Bossa (150/3rd) | |
Session Chairs: Sheng Dai; Session Monitor: TBA |
16:45: [MoltenTuePM211]
Multi-stabilized Pd-SILCA with Nitrogen-rich Ionic Liquids as a Recyclable Catalyst for Heck Reaction Nemanja
Vucetic1 ;
Jyri-pekka
Mikkola1 ;
1Abo Akademi University, Turku, Finland;
Paper Id: 232
[Abstract] The palladium-catalysed reaction between aryl halides or vinyl halides and alkenes in the presence of a base — referred to as the Heck reaction — facilitates the carbon-carbon coupling with preservation of double bond. Next to the common VOC solvents, ionic liquids (ILs) have shown great potential for Heck reaction under homogeneous conditions.[1,2] However, for the recycling of expensive metal heterogenization, this system becomes a necessity. One of the potential methods includes supporting Pd complexes and an ionic liquid in a form of Supported Ionic Liquid Catalyst (SILCA) while avoiding the use of toxic and expensive ligands.
In a present study, we designed new silica supported catalyst with the nitrogen-rich ionic liquid layer that can ligate active palladium. Through the multiple anchoring points, leaching of the metal was suppressed, and catalyst activity was preserved. Optimization was done by changing the support, metal sources, and varying anion-cation parts of ILs. Remarkable activity in different Heck reactions was demonstrated. In order to get a full understanding of the catalyst structure and behaviour, it was characterised by means of nitrogen physisorption, TGA, XRD, FT-IR, solid-state NMR, XPS, SEM and ICP-MS.
References:
[1] Li, S., Lin, Y., Xie, H., Zhang, S. & Xu, J. Bronsted Guanidine Acid "Base Ionic Liquids": Novel Reaction Media for the Palladium-Catalyzed Heck Reaction. Tetrahedron 2003-2006 (2006).
[2] Wang, R., Piekarski, M. M. & Shreeve, J. M. Pyrazolyl-functionalized 2-methylimidazolium-based ionic liquids and their palladium(ii) complexes as recyclable catalysts. Org. Biomol. Chem. 4, 1878 (2006).