| At present, the main inducing factor of global warming is the greenhouse effect which caused by the increase of greenhouse gases such CO2in the atmosphere since the industrial revolution. The industrial application of organic amine solutions exists some problems in decarburization processes, such as volatile, big loss, high energy consumption of regeneration, which seriously affected the greenization and economical efficiency of the process. Ionic liquids are new media and soft functional materials that developed in the fraamework of green chemistry in recent years. Compared with traditional organic solvents, ionic liquids have many unique properties. Ionic liquids, especially functional ionic liquids have a good ability for CO2absorption and fixation.Ionic liquids were regard as main research object in this study, a new type of alcohol amine ionic liquids were synthesized; And the physicochemical properties and their change rule were determined and researched, respectively; Then the solubility of CO2in ionic liquid solutions and the influencing factors were discussed. Combined with hollow fiber membrane contactor, the coupling process of ionic liquids and hollow fiber membrane contactor and its preformance were researched.The result shows, the order of CO2solubility in solutions is MEA-Gly> DEA-Gly> MEA-C; The solubility of CO2in ionic liquids is fitted to the solubility law of gas in solution; With the increase of the proportion of ionic liquids in aqueous solutions, the amount of dissolved CO2in the solutions increase; A moderate amount of activator PZ can greatly enhance the solubility of CO2in the ionic liquids.We can conclude through the data of the physical properties measured under the condition of293.15K to293.15K. The density, viscosity and surface tension of MEA-C are biggest, but its refractive index is smallest in three ionic liquids. The viscosity of MEA-Gly and DEA-Gly are small, which has a great advantage compared with the conventional ionic liquids. The density, viscosity and surface tension of solution decrease as temperature increase, and the decline of viscosity is largest. As water content in solution increase, density, viscosity and refractive index of solution decrease, but the surface tension increase. Activator PZ has a great influence on physical property of solution. Increased water content in the solution, reduce the density, viscosity and refractive index of solution, but it will increase the surface tension of the solution. The data fitting and estimation show that experimental value and theoretical value has a good consistency.The absorption kinetics of CO2in ionic liquid solutions are investigated by bipolar stirred tank absorption reaction device, and we know that:temperature increase, density and viscosity decrease, while solubility coefficient increase; Diffusion coefficient of CO2in ionic liquid solution decrease with increasing of the concentration, increase as the temperature rises; Temperature on the reaction rate of ionic liquids absorb CO2effect is not obvious; In at a certain temperature, the enhancement factor of CO2absorption process in ionic liquid aqueous solution and the square root of the ionic liquid concentration CBl present a linear relationship; Under the different temperature, the secondary reaction rate constant k2of CO2absorption process in ionic liquid aqueous solution increase with the rise of temperatureBased on the performance research of the system of hollow fiber membrane and ionic liquids and the regeneration process, we conclude that the pH and the CO2load in solution have a certain inverse relationship; gas velocity and liquid velocity can improve the mass transfer performance of the membrane contactor and the effect of CO2absorption in ionic liquid; the role of activator PZ on absorption performance of ionic liquids is homogeneous catalysis essentially; the alcohol amine ionic liquids have good regeneration performance, and good circulation absorption regeneration ability, which mean that there are great advantage and practical value in industrial application.Through the research in this paper, we learn that the new alcohol amine ionic liquid have unique physical properties, can play a greater advantage in CO2absorption. By the process coupling of ionic liquid and membrane contactor, the application prospect and economical efficiency of the membrane-based CO2capture system are analyzed. |
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