Investigations of primary and secondary amine carbamate stability by 1H NMR spectroscopy for post combustion capture of carbon dioxide

Fernandes, Debra; Conway, William; Burns, Robert C.; Lawrance, Geoffrey A.; Maeder, Marcel; Puxty, Graeme

doi:10.1016/j.jct.2012.03.030

Cited by 75 publications

(73 citation statements)

References 35 publications

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“…Furthermore, it has been suggested that the formation of intramolecularly hydrogen bonded ring structures may contribute to decreased carbamate stability. 16 The Arrhenius activation energy for 3-PM determined here is significantly larger than the corresponding value for MEA and some other aliphatic amines, the values of which are typically in the range of 40−65 kJ/mol. Chemical explanations for the large values are unclear, however activation energies reported in the literature for the cyclic amines such as piperdine and pyrrolidine, 75.9 and 79.9 kJ/mol, respectively, are similarly larger and close to the activation energies reported here for 3-PM.…”

Section: Introductioncontrasting

confidence: 52%

“…A comparison of the carbamate stability constants and thermodynamic values here with the corresponding values for MEA and a series of cyclic amines in our previous work reveals several similarities. 16 The average value (from the low and high concentration NMR series) for log K 9 = 0.84 at 25.0°C here is considerably lower than the corresponding value for the unhindered parent cyclic amine piperidine (log K 9 = 1.38) and is aligned with the lower end of the range of values (log K 9 = 0.79−2.69) for sterically unhindered cyclic secondary amines at similar temperatures. Considering the stability of 3-PM carbamate is potentially influenced by the formation of an intramolecularly hydrogen bonded structure, any further convolution of this behavior on the magnitude of stability constants is highly complex and beyond the scope of this work.…”

Section: Co 2 Absorption Flux N Co2 and Overall Massmentioning

confidence: 55%

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CO₂ Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO₂ Mass Transfer, Stopped-Flow Kinetics, ¹H/¹³C NMR, and Vapor–Liquid Equilibrium Investigations

Conway

Beyad

Maeder

et al. 2014

Ind. Eng. Chem. Res.

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Global efforts to reduce carbon dioxide emissions stemming from the combustion of fossil fuels have acknowledged and focused on the implementation of post combustion capture (PCC) technologies utilizing aqueous amine solvents to fulfill this role. The cyclic diamine solvent piperazine has received significant attention for application as a CO 2 capture solvent, predominantly for its rapid reactivity with CO 2 . A thorough investigation of alternative but simpler cyclic amines incorporating a single amine group into the cyclic structure may reveal further insight into the superior kinetic performance of piperazine and the wider applicability of such cyclic solvents for PCC processes. One such example is the cyclic monoamine 3-piperidinemethanol (3-PM). To facilitate the evaluation of 3-PM as a capture solvent requires knowledge of the fundamental chemical parameters describing the kinetic and equilibrium of the reactions occurring in solutions containing CO 2 and 3-PM. Additionally, in parallel with the preceding, experimental measurements of CO 2 absorption into 3-PM solutions, including mass transfer and vapor−liquid equilibrium measurements, can be used to validate the CO 2 absorption performance in 3-PM solutions and compared to that of monoethanolamine (MEA) under similar conditions. The present study is focused in two parts on (a) determination of fundamental kinetic and equilibrium constants via the analysis of stopped-flow kinetic and quantitative equilibrium measurements via 1 H/ 13 C nuclear magnetic resonance (NMR) spectroscopy and (b) experimental measurements of CO 2 absorption into 3-PM solutions via wetted wall column kinetic measurements, vapor−liquid equilibrium measurements, and corresponding physical property data including densities and viscosities of the amine solutions over a range of concentrations and CO 2 loadings. Fundamental kinetic rate constants describing the reaction of CO 2 with 3-PM are significantly faster than MEA at similar temperatures (3-PM = 32 × 10 3 M −1 s −1 , extrapolated to 40°C from kinetic data between 15.0 and 35.0°C; MEA = 13 × 10 3 M −1 s −1 , 40°C). Conversely, the equilibrium constants describing the reaction between bicarbonate and amine, often termed carbamate stability constants, are significantly lower for 3-PM than MEA at similar temperatures. Overall CO 2 absorption rates in 3.0 M solutions of 3-PM and MEA, assessed in overall CO 2 mass transfer coefficients, are lower in the former case over the entire range of CO 2 loadings from 0.0 to 0.4 mol of CO 2 per mol of amine. The reduced absorption rates in the 3-PM solutions can be attributed to higher solution viscosities and thus corresponding reductions in CO 2 diffusion. CO 2 absorption and cyclic capacities in 3.0 M solutions of 3-PM and MEA were found to be significantly higher in the case of 3-PM. The larger CO 2 capacities are attributed to the lower stability 3-PM carbamate and the formation of larger amounts of bicarbonate compared to MEA. Overall, the larger CO 2 absorption capacity, cyclic capacity, ...

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Section: Introductioncontrasting

confidence: 52%

Section: Co 2 Absorption Flux N Co2 and Overall Massmentioning

confidence: 55%

CO₂ Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO₂ Mass Transfer, Stopped-Flow Kinetics, ¹H/¹³C NMR, and Vapor–Liquid Equilibrium Investigations

Conway

Beyad

Maeder

et al. 2014

Ind. Eng. Chem. Res.

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“…7(b)), after CO 2 absorption, a range of products existed in [N 1111 This reaction was essentially a base-catalyzed CO 2 hydrolysis, i.e., [N 1111 ][Gly] did not combine with CO 2 . The reaction product was bicarbonate, which was known to be a dominant product for sterically hindered amines such as methyldiethanolamine (MDEA) and 2-amino-2-methyl-1-propanol (AMP) (Chakraborty et al, 1986;Donaldson and Nguyen, 1980;Fernandes et al, 2012). For instance, the reaction between CO 2 and AMP (RNH 2 ) (where R = C(CH 3 ) 2 CH 2 OH) was shown in the following equation (Fernandes et al, 2012):…”

Section: Absorption/desorption Mechanismmentioning

confidence: 99%

Regeneration performance and absorption/desorption mechanism of tetramethylammonium glycinate aqueous solution for carbon dioxide capture

Guo

Jing

Zhou

2015

International Journal of Greenhouse Gas Control

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“…[34] The latteri sf ormed while performing the ATR-IR measurement under air.H owever,t he formation of au rea group in [10]-OU was confirmed by ap eak at 1251 cm À1 (A), which is assigned to the single bond CÀN. [35] The latter peak is determinant to differentiate between the existence of au rea group or ac arbamate.…”

Section: Resultsmentioning

confidence: 99%

[n]‐Oligourea‐Based Green Sorbents with Enhanced CO₂ Sorption Capacity

et al. 2015

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A new series of [n]-oligoureas ([n]-OUs, n=4, 7, 10, and 12) green solid sorbents was prepared following a base-catalyzed, microwave-assisted oligomerization reaction. The materials were characterized by NMR and IR spectroscopy, elemental analysis, thermogravimetric analysis, differential scanning calorimetry, and XRD. Decomposition temperatures at 50 % weight loss (Td50 ) were ca. 350 °C for all oligomers. Urea and urethane functional groups indicated by IR spectroscopy confirmed the formation of the sorbent. The CO2 capturing capacities were determined at 35 °C and 1.0 bar (gravimetric method). Accordingly, [10]-OU had the highest CO2 sorption capacity among the others (18.90 and 22.70 mg CO 2 gsorbent (-1) ) at two different activation temperatures (60 or 100 °C, respectively). Chemisorption was the principal mechanism for CO2 capture. Cyclic CO2 sorption/desorption measurements were carried out to test the recyclability of [10]-OU. Activating the sample at 60 °C, three stable CO2 sorption cycles were achieved after running the first cycle.

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Investigations of primary and secondary amine carbamate stability by 1H NMR spectroscopy for post combustion capture of carbon dioxide

Cited by 75 publications

References 35 publications

CO₂ Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO₂ Mass Transfer, Stopped-Flow Kinetics, ¹H/¹³C NMR, and Vapor–Liquid Equilibrium Investigations

CO₂ Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO₂ Mass Transfer, Stopped-Flow Kinetics, ¹H/¹³C NMR, and Vapor–Liquid Equilibrium Investigations

Regeneration performance and absorption/desorption mechanism of tetramethylammonium glycinate aqueous solution for carbon dioxide capture

[n]‐Oligourea‐Based Green Sorbents with Enhanced CO₂ Sorption Capacity

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Investigations of primary and secondary amine carbamate stability by 1H NMR spectroscopy for post combustion capture of carbon dioxide

Cited by 75 publications

References 35 publications

CO2 Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO2 Mass Transfer, Stopped-Flow Kinetics, 1H/13C NMR, and Vapor–Liquid Equilibrium Investigations

CO2 Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO2 Mass Transfer, Stopped-Flow Kinetics, 1H/13C NMR, and Vapor–Liquid Equilibrium Investigations

Regeneration performance and absorption/desorption mechanism of tetramethylammonium glycinate aqueous solution for carbon dioxide capture

[n]‐Oligourea‐Based Green Sorbents with Enhanced CO2 Sorption Capacity

Contact Info

Product

Resources

About

CO₂ Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO₂ Mass Transfer, Stopped-Flow Kinetics, ¹H/¹³C NMR, and Vapor–Liquid Equilibrium Investigations

CO₂ Absorption into Aqueous Solutions Containing 3-Piperidinemethanol: CO₂ Mass Transfer, Stopped-Flow Kinetics, ¹H/¹³C NMR, and Vapor–Liquid Equilibrium Investigations

[n]‐Oligourea‐Based Green Sorbents with Enhanced CO₂ Sorption Capacity