Modelling the solubility of H2S and CO2 in ionic liquids using PC-SAFT equation of state

The Perturbed Chain Statistical Association Fluid Theory (PC-SAFT) is used to investigate the solubility of carbon dioxide (CO2) and hydrogen sulfide (H2S) in several methylimidazolium bis (trifluoromethylsulfonyl) imide ionic liquids (ILs) or [Cnmim][NTf2] where n = 2; 4; 6 and 8. The pure component parameters of the studied ILs are estimated by fitting to experimental density data and binary solubility data of acid gases in ILs reported in literature. Two strategies are examined to model the studied ILs. In the first strategy, ILs are modelled as neutral molecules. As for the second strategy, ILs are modelled as charged ions: imidazolium cation [Cnmim]+ and bis (trifluoromethylsulfonyl) imide anion [NTf2]-. For each strategy, four different self association schemes are examined. The schemes are: non associating, 2-sites, 3-sites and 4-sites scheme. Results indicated that, the inclusion of the association term improves the solubility fit. The 4-sites association scheme with two donors and two acceptors provided the best results for almost all investigated acid gases-IL binary systems with AARD% of (7.48%–2.76%) for H2S-ILs systems and (4.98%–1.45%) for CO2-IL systems. The solubility of acid gases in the ILs is successfully represented using PC-SAFT without the need for any binary interaction parameters if the proper association scheme is selected. The inclusion of the electrolyte term in the second strategy improves the predictive capability of the model by allowing for the examination of the effect of using different cation-anion combinations

Acid gas removal from natural gas using ionic liquids

The growth in demand for natural gas accounted for almost half the increase in global energy consumption in 2018 and is projected to increase by more than 10% over the next five years. This is due to its abundancy, efficiency and lower carbon content compared to oil and coal. However, raw gas contains undesirable components, such as hydrogen sulphide and carbon dioxide, which must be removed before its delivery to end users because of their toxicity, corrosivity, flammability and poor heating value.;Various technologies have been used for acid gas removal. Amine-based absorption is the most widely used technique; however, they are corrosive, volatile, degrade at high temperatures and highly energy intensive to regenerate. This study aims to improve pre-existing amine processes by reducing their energy consumption and environmental impact through the use of ionic liquids (ILs) and their blend with other physical solvents as an alternative to amines.;The consequences of replacing an amine with ILs or a blend of ILs with other physical solvent in an existing amine unit are examined and found to be promising. A thermodynamic description of the IL mixtures needed to be developed to examine their use to replace amine solutions. The perturbed chain statistical association fluid theory (PC-SAFT) is selected as the thermodynamic model to represent the vapour liquid equilibrium of acid gases-IL systems.;The solubility of gases in ILs was successfully described without the need for empirical binary interaction parameters, as was required in previous studies. Up to 47% and 7% of the regeneration energy and the total annual cost, respectively, were saved by using IL instead of amine, while up to 40% and 27% of the regeneration energy and the total annual cost, respectively, were saved by using a blend of IL with other physical solvent.The growth in demand for natural gas accounted for almost half the increase in global energy consumption in 2018 and is projected to increase by more than 10% over the next five years. This is due to its abundancy, efficiency and lower carbon content compared to oil and coal. However, raw gas contains undesirable components, such as hydrogen sulphide and carbon dioxide, which must be removed before its delivery to end users because of their toxicity, corrosivity, flammability and poor heating value.;Various technologies have been used for acid gas removal. Amine-based absorption is the most widely used technique; however, they are corrosive, volatile, degrade at high temperatures and highly energy intensive to regenerate. This study aims to improve pre-existing amine processes by reducing their energy consumption and environmental impact through the use of ionic liquids (ILs) and their blend with other physical solvents as an alternative to amines.;The consequences of replacing an amine with ILs or a blend of ILs with other physical solvent in an existing amine unit are examined and found to be promising. A thermodynamic description of the IL mixtures needed to be developed to examine their use to replace amine solutions. The perturbed chain statistical association fluid theory (PC-SAFT) is selected as the thermodynamic model to represent the vapour liquid equilibrium of acid gases-IL systems.;The solubility of gases in ILs was successfully described without the need for empirical binary interaction parameters, as was required in previous studies. Up to 47% and 7% of the regeneration energy and the total annual cost, respectively, were saved by using IL instead of amine, while up to 40% and 27% of the regeneration energy and the total annual cost, respectively, were saved by using a blend of IL with other physical solvent

Application of Platelet-Rich Fibrin as Regeneration Assistant in Immediate Auototransplantation of Third Molar with Unformed Roots: Case Report and Review of Literature

Background. Autogenous Tooth Transplantation (ATT) is the surgical movement of a maturely or immaturely formed tooth from its original site to another extraction site or a surgically prepared socket in the same individual. The most important factor in the healing process after autotransplantation is the presence of intact and viable periodontal ligament cells, which have the ability to differentiate into osteoblasts and able to induce bone production. ATT can successfully replace removable dentures as a restoration option in a growing patient, while implants can be placed only after skeletal maturity is attained. Case Presentation. In this case, we presented an immediate ATT of the third molar with unformed roots to the extraction socket of the first molar with evidence of continued root formation after 2 years of follow-up. Conclusion. Platelet-Rich Fibrin (PRF) can induce sustainable and accelerated healing, and it can also induce the regeneration process of the periodontal tissues and pulpal formation. This process plays a key role in future root development and success rate