| 1. |
- da Silva Ramos, Alessandro, et al.
(författare)
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Synthesis of new CO2 hydrate inhibitors
- 2020
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Ingår i: Journal of Natural Gas Science and Engineering. - : Elsevier. - 1875-5100 .- 2212-3865. ; 75, s. 1-6
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Tidskriftsartikel (refereegranskat)abstract
- Gas hydrate is a crystalline compound made of water and mainly of gases methane and carbon dioxide under specific conditions of pressure and temperature. Increasing worldwide petroleum exploitation in deep waters, where these conditions are encountered, favours the precipitation of gas hydrate in seafloor pipelines, resulting in partial or total obstruction of petroleum flow. Brazil's largest petroleum reserves of the pre-salt interval, for example, are located in ultra-deep waters (>1500 m) and may have a gas composition of up to 80% of CO2. Huge investments are necessary to inhibit the formation of gas hydrate and to assure petroleum flow in pipelines. Here we present the results of the synthesis of new organic compounds obtained from L-Threonine, which show a high potential to be used as CO2 hydrate inhibitors. This characteristic is related to the increase carbon chain in each molecule (higher hydrophobicity) leading to a reduction on CO2 solubility in water. In addition to that, our study also shows the occurrence of the “salting out effect” and reduced water activity coefficient.
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| 2. |
- Pires, Jessica Pereira, et al.
(författare)
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Analysis of the Effect of Organic Salts Derived from L-Phenylalanine Amino Acid as Kinetic Promoters/Inhibitors of CO2 Hydrates
- 2021
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Ingår i: Energy & Fuels. - : American Chemical Society (ACS). - 0887-0624 .- 1520-5029. ; 35:9, s. 8095-8101
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Tidskriftsartikel (refereegranskat)abstract
- Carbon dioxide capture, storage, and transport technology based on the formation of gas hydrate is an innovative solution. In this work, the experimental investigations on the formation of CO2 hydrates were carried out with aqueous solutions containing 0.5% by weight of three different organic salts synthesized from L-phenylalanine and different alcohols under isochoric conditions. All of the synthesized compounds were obtained with good yields (74.2-87.7%), and among them, the nonyl L-phenylalanine hydrochloride is an unprecedented compound. In addition, there has not been any study with organic salts aiming to verify their influence as an inhibitor or promoter of CO2 hydrates. The compound pentyl L-phenylalanine hydrochloride showed a successful result in promoting CO2 hydrate since it achieved a shorter induction time (1.74 h), a higher CO2 consumption rate, and better storage capacity (slope of the pressure curve). In addition, dodecyl L-phenylalanine hydrochloride has the characteristic of CO2 hydrate inhibitor, and therefore it was observed that the increase of the side-chain hydrophobicity (carbon chain linked to the oxygen function of the ester function) provides the effect of inhibiting CO2 hydrates.
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| 3. |
- Ramos, Alessandro da Silva, et al.
(författare)
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Organic salts as kinetic and thermodynamic inhibitors for CO2 hydrate precipitation
- 2020
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Ingår i: Journal of Natural Gas Science and Engineering. - : Elsevier. - 1875-5100 .- 2212-3865. ; 82, s. 1-8
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we opted for the use of CO2 gas for the respective experiments, due to its greater solubility in water when compared to hydrocarbons, as well as possible applications in pre-salt oil fields (such as the Libra field), where the amount of CO2 varies between 40 and 80%, obstructing the pipelines in the CO2 capture stage. In this context, the objective of this work is to obtain organic salts of different amino acids and alcohols (biodegradable and environmentally friendly compounds) and to test them in a pilot gas hydrate synthesis plant, with the goal of evaluate the inhibition potential of these compounds for CO2 hydrates. The organic compounds were synthesized with good yields and were characterized by NMR (C-13 and H-1) and elementary analysis. The compounds with greater hydrophilic character showed thermodynamic inhibition effects for the tested condition, while the hydrophobic compounds showed kinetic inhibition effects. The fundamental knowledge and the mechanism on the kinetic and/or thermodynamic inhibition of CO2 hydrates from organic salts obtained in this study are beneficial and extremely important, given the good results presented and the unprecedented application of the tested compounds.
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