Immobilized Ionic Liquid For The Acid Gas Separation

Room temperature ionic liquids(ILs)is a novel kind of benign solvent with high potential in replacing the Volatile Organic Compounds(VOCs),which also provides a possible approach to reduce or eliminate the environmental pollution from the chemical reactions and chemical engineering.Some ILs also exhibit good selective sorption ability for acid gases,but their high viscosity has a negative affect on their application as liquid absorbent for acid gases.In this paper,we immobilize ILs TMGL in porou Silica gel through a simple impregnation-vaporization method.The resulted immobilized TMGL Silica gel particle(TMGL·SiO₂)obtained both solid silica gel properties of high sepecial surface,porosity and good mechanical and liquid ILs properties of low vapor press and good gas sorption ability.TMGL·SiO₂ has a high gas sorption velocity and capacity reaching an equilibrium sorption capacity of 0.6g SO₂/g TMGL(1.92 mol SO2/mol TMGL)within 15～30 min in pure SO₂ gas and of 0.13 g SO₂/g TMGL in a SO₂/N₂ mixture gases containing 2160 ppm SO₂ (around 0.2 vol%SO₂).We also explore the new SO₂ absorbent for high temperature flue gas desulfurization,nature gas H₂S sorption and membrane process for acid gases separation.New ILs lysine tetramethylgradium(TMGLy)which contains more nitrogenous groups will absorb/adsorb 2.9 mol SO₂/mol TMGLy at 30℃and 1.3 mol SO₂/mol TMGLy at 120℃.For H₂S sorption in nature gas,TML will absorb/adsorb 0.25 mol H₂S/mol TMGL.PTMGA-co-MBA/Al₂O₃ organic/inorganic composite membrane exhibits a higher permitability for N₂ rather than SO₂ which did not achieve the SO₂ selective permitability purpose.