Search

[Display omitted] • An innovative amine-based thermal energy storage (ATES) technology was developed. • ATES system utilize 84% of CO 2 reaction enthalpy for heat output. • The system obtained high-grade heat at ∼130 °C and energy density of 210 kJ/kg. • System energy efficiency of 70% was obtained via regeneration energy improvement. Thermal energy storage (TES) bridges the intermittence of renewable energy to generate steady and efficient clean energy. While amine-based CO 2 capture is a leading technology for CO 2 emission reduction, we innovatively employed the amine technology for long-term thermal energy storage, namely amine-based TES (ATES). The system utilises the thermally reversible amine-CO 2 reaction as the energy storage working pair, where low-grade thermal energy is used to break the amine-CO 2 chemical bond with the heat stored and released via exothermic amine-CO 2 reaction to produce high-quality thermal energy when required. Using benchmark absorbent monoethanolamine (MEA), we simulate and optimize the ATES system, and demonstrate that ATES exhibits desirable thermal energy storage performance with high-quality heat output up to 131 °C, high thermal energy conversion efficiency of >70%, moderate energy density of 210 kJ/kg and long-term storage, which outperforms the water-based sensible thermal storage technology. More importantly, the ATES is built on commercially viable amine process and heat exchange system, indicating its great potential for commercial applications, such as space heating and industrial waste heat storage. [ABSTRACT FROM AUTHOR]

Abstract: This paper studies an ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl) imide ([EMIM][TFSI]) containing Zn2+ ions as a novel functional group for CO2 absorption. Their physical properties including the density, decomposition temperature, phase transition temperature, heat capacity and viscosity have been characterised. The CO2 solubility measurements have been carried out under constant pressures of 0.1, 0.3, 0.5, 0.7 and 1.0 bar at 40 °C. The result shows an appealing solubility of 8.2 wt% CO2 at 1.0 bar. The real-time absorption kinetics was studied using a comprehensive diffusion model for a reacting system. Based on this model, the corresponding diffusion coefficients and the reaction rate constant have been obtained. The diffusion and reaction behavior of CO2 in the physical/chemical absorption has also been discussed. [Copyright &y& Elsevier]

Abstract: Fourier transform infrared spectroscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy were applied in this study to demonstrate that multi-walled carbon nanotubes synthesized from ethanol flames (F-MWCNTs) inherently have functional groups on their surfaces. This finding clearly indicates that the covalent functionalization of carbon nanotubes can be achieved without oxidation as pretreatment. Thus, n-hexadecylamine functionalized F-MWCNTs (H-MWCNTs) can be synthesized simply, without disrupting the primary structures of the nanotubes. The melt-compounding method was used to fabricate polyamide 6/MWCNTs composites. Scanning electron microscope results confirmed that both F-MWCNTs and H-MWCNTs have much better nanoscopic dispersion in PA6 matrix than commercial MWCNTs, and the tensile strength, Young’s modulus, dynamic mechanical properties, and thermal behavior of their PA6 composites are considerably improved. [Copyright &y& Elsevier]

Highlights: [•] For IL modified silica, CO2 adsorption depends on the porous nature of the silica. [•] The IL phases act as a selecting film which notably improves CO2/N2 selectivity. [•] The grafting method provides a good IL retention with gas cycling. [•] Diffusion coefficient in modified silica is in range of 10−8–10−7 m2/s using HSDM. [ABSTRACT FROM AUTHOR]