Synthesis Of Ionic Polymer With Low Specific Surface And Its Adsorption Performance Of Sulfur Dioxide

The emission of SO₂ from the burning of fossil fuels is major contributor to haze and acid rain,which poses a great threat to the environment and human health.The concentration of SO₂ in flue gas is usually less than 1%,and flue gas also contains competitive gas molecules such as CO₂ and N₂.Traditional porous adsorbents have relatively large specific surface areas and result to unsatisfied adsorption selectivity of SO₂/CO₂and SO₂/N₂.Therefore,it is of great significance to study and develop new solid adsorbents to achieve high capacity and selectivity adsorption of SO₂/CO₂ and SO₂/N₂.In this thesis,two kinds of ionic polymer with low specific surface areas were synthesized and used as the adsorbents for SO₂ adsorption.The contents were as follows:(1)Three ionic polymers with low specific surface areas were successfully prepared through one-pot free radical copolymerization process.The selective adsorption and separation of SO₂ from CO₂ and N₂ was then studied.The results showed that the SO₂ adsorption capacity by guanidinium-based ionic polymer P([Alyl-TMG]Br-DVB)was up to 9.79 mmol/g,but the N₂ and CO₂ adsorption capacity was only 0.01 and 0.07 mmol/g at 298 K and 1.0 bar,respectively.The selectivity of SO₂/CO₂ and SO₂/N₂ was 452 and 2294,respectively.The breakthrough tests confirmed that P([Alyl-TMG]Br-DVB)had good performance for adsorption and separation of 2000 ppm SO₂,and the breakthrough time was as high as 150min/g.(2)Three phenolic based-ionic polymers with low specific surfaces were designed and prepared,and the selective adsorption for SO₂/CO₂ and SO₂/N₂ were then studied.The results showed that the SO₂ adsorption capacity of phenolic-based ionic polymer ILG-0.15 was up to 10.58 mmol/g at 298 K and 1.0 bar,and the SO₂/CO₂ and SO₂/N₂adsorption selectivity were 120 and 7271,respectively.Moreover,the breakthrough tests confirmed that P([Alyl-TMG]Br-DVB)also had good separation performance of2000 ppm SO₂,and the breakthrough time was as high as 487 min/g.In addition,the ionic polymer ILG-0.15 also showed good reusability and the SO₂ adsorption capacity did not change obviously after 8 cycles.