TY - JOUR
T1 - Probing the effect of amino acid-based ionic liquids on the CO2 (sI) and THF (sII) hydrate formation
AU - Soromenho, Mário R. C.
AU - Keba, Anastasiia
AU - Esperança, José M. S. S.
AU - Tariq, Mohammad
N1 - info:eu-repo/grantAgreement/FCT/Concurso para Financiamento de Projetos de Investigação Científica e Desenvolvimento Tecnológico em Todos os Domínios Científicos - 2017/PTDC%2FEQU-EQU%2F32050%2F2017/PT#
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB%2F50006%2F2020/PT#
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDP%2F50006%2F2020/PT#
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/LA%2FP%2F0008%2F2020/PT#
Funding Information:
The authors would like to thank Fundação para a Ciência e Tecnologia, FCT/MCTES (Portugal), for financial support through project PTDC/EQU-EQU/32050/2017. This work was partially supported by the Associate Laboratory for Green Chemistry—LAQV, which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020 and LA/P/0008/2020).
Publisher Copyright:
© 2023 The Author(s)
PY - 2024/1/15
Y1 - 2024/1/15
N2 - In the present work, four acetyl glycinate-based ionic liquids (ILs) with distinct cations, namely 1-alkyl-3-methylimidazolium acetyl glycinate [C2mim][AcGly], ammonium acetyl glycinate [NH4][AcGly], N-(2-hydroxyethyl)-N,N,N-trimethyl ammonium N-acetylglycinate [N111(2OH)][AcGly] ≈ [Ch][AcGly], and N-Butyl-N,N-dimethyl-N-(2-hydroxyethyl) ammonium N-acetylglycinate [N411(2OH)][AcGly] ≈ [C4Ch][AcGly], were synthesized and tested for their effect on the formation of CO2 hydrates at elevated pressures and tetrahydrofuran (THF) hydrate formation at atmospheric pressure. The phase behaviour of the CO2 hydrates, sI type, was studied in the presence of the selected ILs using the isochoric pressure search method. The ILs shifted the phase boundary towards lower temperatures indicating a thermodynamic inhibition characteristic. The constant cooling method was used to determine the onset nucleation temperature of CO2 hydrates in the presence and absence of additives. The isothermal method was used to determine the induction time of CO2 hydrates in the presence of additives. The pressure drops in both experiments indicate the hydrate growth in the absence/presence of additives. Later, the THF hydrate crystal growth experiments at atmospheric pressure were carried out to understand the effect of additives on the sII-type hydrate growth. The crystal morphology also points out the mode of action of the tested additives on hydrate formation and growth. The extensive testing using the same additives at identical concentrations revealed the importance of the method and conditions, which become crucial in the absence of a standard screening procedure for kinetic hydrate additives.
AB - In the present work, four acetyl glycinate-based ionic liquids (ILs) with distinct cations, namely 1-alkyl-3-methylimidazolium acetyl glycinate [C2mim][AcGly], ammonium acetyl glycinate [NH4][AcGly], N-(2-hydroxyethyl)-N,N,N-trimethyl ammonium N-acetylglycinate [N111(2OH)][AcGly] ≈ [Ch][AcGly], and N-Butyl-N,N-dimethyl-N-(2-hydroxyethyl) ammonium N-acetylglycinate [N411(2OH)][AcGly] ≈ [C4Ch][AcGly], were synthesized and tested for their effect on the formation of CO2 hydrates at elevated pressures and tetrahydrofuran (THF) hydrate formation at atmospheric pressure. The phase behaviour of the CO2 hydrates, sI type, was studied in the presence of the selected ILs using the isochoric pressure search method. The ILs shifted the phase boundary towards lower temperatures indicating a thermodynamic inhibition characteristic. The constant cooling method was used to determine the onset nucleation temperature of CO2 hydrates in the presence and absence of additives. The isothermal method was used to determine the induction time of CO2 hydrates in the presence of additives. The pressure drops in both experiments indicate the hydrate growth in the absence/presence of additives. Later, the THF hydrate crystal growth experiments at atmospheric pressure were carried out to understand the effect of additives on the sII-type hydrate growth. The crystal morphology also points out the mode of action of the tested additives on hydrate formation and growth. The extensive testing using the same additives at identical concentrations revealed the importance of the method and conditions, which become crucial in the absence of a standard screening procedure for kinetic hydrate additives.
KW - Acetyl glycine
KW - CO hydrates
KW - Ionic liquids
KW - Nucleation temperature
KW - Phase behaviour
UR - http://www.scopus.com/inward/record.url?scp=85180438351&partnerID=8YFLogxK
U2 - 10.1016/j.molliq.2023.123744
DO - 10.1016/j.molliq.2023.123744
M3 - Article
AN - SCOPUS:85180438351
SN - 0167-7322
VL - 394
JO - Journal of Molecular Liquids
JF - Journal of Molecular Liquids
M1 - 123744
ER -