Preparation Of Non-water Amino Ionic Liquid Microcapsules And Effects On CO₂ Absorption

With the rise of the industrial revolution,emissions of carbon dioxide have risen rapidly because of the develop of industry and economy.The excessive emission of CO2 has caused serious greenhouse effect,making CO2 capture a significant global issue.There are many carbon dioxide capture methods,such as physical absorption,chemical absorption,membrane separation and so on.Among them,aqueous solutions of organic amines are most widely used which have the advantages of high absorption rate and large absorption capacity.However,these absorbents suffer from high causticity and high regeneration costs,which greatly limit industrial applications.Ionic liquids that have obvious advantages of low vapor pressure,high thermal stability and high designability have been studied for CO2 capture.However,the high viscosity strongly weakens the absorption performance.Accordingly,low viscosity solvents such as water or organic amines are introduced to reduce viscosities and increase the absorption capacity of ILs,but the compound absorbents also have high regeneration energy costs."Dry water" is a powdery substance prepared by hydrophobic silica particles and water with high-speed stirring."Dry water" has been widely used in all walks of life since its discovery."Dry water" is also used for gas separation."Dry matter" containing different liquids was prepared too."Dry ionic liquid" prepared by ionic liquid solutions has excellent CO2 absorption performance.The core liquids of "dry matter" contains water mainly because the high surface tension is an essential factor for the formation of"dry matter".However,"dry matter" can be easily damaged because of the loss of water who has volatility.In this work,the amino ionic liquid[N1111][Gly](tetramethylammonium glycine)was mixed with nonaqueous solvents ethylene glycol(EG)and glycerol(GL)the surface tensions of which are also high and the amino ionic liquid nanocapsules "dry ionic liquids"(D-IL)were prepared successfully.[N1111][Gly]was synthesized and compounded with EG and GL at different mass fractions(10%,20%,30%,40%,60%,80%)and corresponding D-ILs were successfully prepared.The densities,viscosities and surface tensions of the liquid compound absorbents,as well as the specific surface areas,particle sizes and true densities of D-IL were characterized and their ideal morphology were predicted.In the study of carbon dioxide absorption performance,the absorption curves of liquid compound absorbents and their corresponding D-ILs were compared.It is found that the absorption capacities have no big difference,but the absorption rate of D-IL is much greater.Regeneration experiments show that D-IL has extremely high regeneration efficiency,nearly 100%at 50kPa and 30℃.