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• Rigorous study of thermodynamic effect of three amines (APTES, APTMS, and TETA) on methane hydrates. • APTES, APTMS, and TETA shift the hydrate equilibrium curve to higher pressure and lower temperature. • All three show thermodynamic-inhibition effects similar to lower-concentration case (7 wt%), but with increasing concentration to 20 wt% in the order APTES > APTMS > TETA. • Average hydrate-suppression temperature (ΔT) increased with increasing amine concentration. • Hydrate-onset time was delayed due to synergistic inhibition effect of two inhibitors. • Amines have a kinetic effect on gas-hydrate formation after several cycles with the memory effect. • Amines' inhibition impact was compared with conventional hydrate thermodynamics - similar to ethylene glycol at 5 wt%. The present paper presents an experimental study on the thermodynamic effect of three amines including (3-Aminopropyl)triethoxysilane (APTES), (3-Aminopropyl)triethoxysilane (APTMS), and Triethylenetetramine (TETA) on methane hydrates. Hydrate-Liquid-Vapour Equilibrium (HLwVE) data for methane hydrate were evaluated in the presence of 7 wt% and 20 wt% APTES, APTMS, and TETA, and with pressure ranging from 2.0 to 9.0 MPa. The thermodynamic effect of these amines on methane-hydrate formation has been investigated via measuring the methane-hydrate dissociation temperature, in applying an isochoric pressure-search method. The results reveal that APTES, APTMS, and TETA effectively shift the hydrate equilibrium curve to higher-pressure and lower-temperature regions for the methane + amine + water system. All of these three show thermodynamic-inhibition effects similar to the lower-concentration case (7 wt%), but with increasing concentration to 20 wt% for the thermodynamic-inhibition effect in the order APTES > APTMS > TETA. The average hydrate-suppression temperature (ΔT), as a 'signature' of thermodynamic-inhibition effect on methane hydrates measured for 7 wt% APTES, APTMS and TETA was 1.5, 1.5, and 1.3 K, respectively. ΔT increased with increasing amine concentration; these values were 5, 4.3, and 3.2 for 20 wt% APTES, APTMS, and TETA, respectively. Hydrate-onset time was further delayed due to the synergistic inhibition effect of inhibitors. The results show that these amines have a kinetic effect on gas-hydrate formation, such as for methane-hydrate formation in presence of APTMS: here, the hydrate formed after several cycles with the help of the memory effect. Moreover, the inhibition impact of these amines was compared with conventional hydrate thermodynamics, and found to be in the range of some and similar to ethylene glycol at 5 wt%. Furthermore, the addition of 5 wt% APTMS to sea salt not only enhances the thermodynamic inhibition effect, but also inhibits kinetically the formation of methane hydrate. For modelling of methane-hydrate dissociation conditions, the solid-solution theory of van der Waals and Platteeuw was applied for the hydrate phase along with the Peng–Robinson equation of state for the gas phase. Taken together, this study elucidates a novel class of thermodynamic hydrate inhibitors, which can control methane-hydrate formation efficiently. [ABSTRACT FROM AUTHOR]

Feedstock-to-fuel conversion, or "Fuel Production", is a major contributor to greenhouse gas (GHG) emissions in life cycle assessment (LCA) of sustainable aviation fuels (SAF) from wastes. Here we construct and demonstrate an original mass and energy conserved chemically rigorous LCA methodology for the production of Hydroprocessed Esters and Fatty Acids-Synthetic Paraffinic Kerosene (HEFA-SPK) from Used Cooking Oil (UCO). This study proposes and demonstrates the use of; (i) the chemical composition of the UCO, (ii) the ASTM properties of HEFA-SPK, and (iii) the elemental mass and energy conserved reaction mechanism which converts one to the other, as physical constraints for the specific LCA of any UCO derived HEFA-SPK. With application of these constraints, the emissions embodied in UCO HEFA-SPK Fuel Production is found to range from 4.2 to 15.7 gCO 2 e/MJ SAF depending on the renewability of the energy and hydrogen utilized. Imposition of (i)-(iii) as modelling constraints, derives a HEFA-SPK yield of 49 mass% a priori. This finding aligns with experimental literature, but brings attention to the higher yield estimations of 70–81% observed in current LCA tools. We show that this impacts the end LCA significantly as it adjusts allocation of emissions. A replication study of CORSIA's (10.5 gCO 2 e/MJ SAF) default core LCA value for Fuel Production, quantifies the increase at +5.3 gCO 2 e/MJ SAF, or 15.8 gCO 2 e/MJ SAF as total for Fuel Production. As the embodied emissions are significantly dependent on the specifics of the scenario assessed, we highlight reporting a definitive GHG intensity for any UCO derived HEFA-SPK as generic will be inaccurate to an extent. [Display omitted] • Novel mass and energy balanced methodology to assess Fuel Production emissions. • Actual allowable ASTM HEFA-SPK is modelled and assessed. • Unit Processes of Fuel Production are individually and transparently assessed. • Electricity and green hydrogen use in Fuel Production decrease LCA emissions. • Methodology is more representative and realistic than current LCA tools. [ABSTRACT FROM AUTHOR]

[Display omitted] • a(b)-planes of HA and Glu of BSA have critical roles in attachment together. • The interaction between BSA and HA surface was studied through a molecular dynamics simulation. • Experimental confirmed MD simulation according to BSA coiling around HA. • BSA improved the bio-mineralization of nano-fibrous PCL scaffolds. The nano-fibrous polycaprolactone (PCL) scaffolds are one of the promising materials for bone tissue engineering. However, the role of protein in the bio-mineralization of PCL fibers is not clear. This study aims to find how a protein (e.g. bovine serum albumin (BSA)) is attached to the hydroxyapatite (HA) nanoparticles (NPs) loaded on the PCL fiber, and it affected the bio-mineralization of a hybrid scaffold. The molecular dynamic (MD) simulation was utilized to explore the protein and HA attachment. The results of MD simulation indicated that the a(b)-planes of HA crystal and glutamic acid (Glu) from BSA molecule have critical roles in attachment together. In the following, the electrospinning method was applied to synthesize the pristine and hybrid PCL scaffolds to evaluate the MD results. The scanning electron microscopy (SEM) images showed that BSA could be successfully attached to the HA NPs, and coiled around the PCL-HA junction confirming the MD simulation. To evaluate the bio-mineralization, the in-vitro immersion test in the simulation body fluid (SBF) solution and the cytocompatibility of scaffolds by the MG63 osteosarcoma cells were studied. The results indicated better osteoconduction and bone regeneration for the hybrid PCL- BSA-HA scaffold because of the synergic effects of HA NPs and BSA protein. [ABSTRACT FROM AUTHOR]