Carbon dioxide capture from industrial gases (i.e., flue gases and natural gas) is a crucial process for reducing the environmental impacts of acid gas emissions. However, carbon dioxide capture that is generally performed by amine-based solvent faces operational problems due to the properties of the solvent. Recently, ionic liquids (ILs) have emerged as promising candidates for replacing the amine-based solvent due to their low vapor pressure (near-zero), high stability, as well as tunable structure and properties. The functionalized ILs are considered superior in terms of their ease of regeneration as well as high absorption capacity and selectivity toward CO2. Combining the functionalized ILs with membrane processes has opened up a new horizon in CO2 capture technology. This review comprehensively summarizes the latest developments in the application of ionic liquid membranes (ILMs) for CO2 capture, including supported ILMs (SILMs), poly-ILMs (PILMs), polymer-IL composite membranes, mixed-matrix-membranes, with special attention to ILM contactors. The absorption mechanisms of CO2 in the ILs are pictured and discussed.
Mercury (Hg) is one of heavy metals with the highest toxicity and negative impact on the biological functions of living organisms. Therefore, many studies are devoted to solving the problem of Hg separation from wastewater. Membrane-based separation techniques have become more preferable in wastewater treatment area due to their ease of operation, mild conditions and also more resistant to toxic pollutants. This technique is also flexible and has a wide range of possibilities to be integrated with other techniques. Graphene oxide (GO) and derivatives are materials which have a nanostructure can be used as a thin and flexible membrane sheet with high chemical stability and high mechanical strength. In addition, GO-based membrane was used as a barrier for Hg vapor due to its nano-channels and nanopores. The nano-channels of GO membranes were also used to provide ion mobility and molecule filtration properties. Nowadays, this technology especially nanofiltration for Hg removal is massively explored. The aim of the review paper is to investigate Hg removal using functionalized graphene oxide nanofiltration. The main focus is the effectiveness of the Hg separation process.
In this study, imidazole derivative-based new ionic liquids were investigated as corrosion inhibitors. These new ionic liquids (ILs) are 1,3-dipropyl-2-(2-propoxyphenyl)-4,5-diphenylimidazole iodide (IL1) and 1,3-dibutyl-2-(2-butoxyphenyl)-4,5-diphenylimidazole iodide (IL2). The corrosion inhibition effects of two new ILs were observed on carbon steel in brackish water media (1% NaCl solution). Carbon steel coupons were exposed to 1% NaCl solution with various concentrations of ILs. Corrosion inhibition effects were tested by the electrochemical impedance spectroscopy (EIS) method and the Tafel method at various temperatures ranging from 25 °C to 55 °C. The results showed that ILs have potential as corrosion inhibitors and the adsorption mechanisms of IL1 and IL2 on carbon steel surfaces were also determined, which followed the Langmuir adsorption isotherm model. Acquisition of ∆Gads values of IL1 and IL2 were −35.04 and −34.04 kJ/mol, respectively. The thermodynamic data of the ILs show that semi-chemical and or physical adsorptions occurred on carbon steel surfaces.
20 April 2022 in Chemical Engineering Journal Advances