Preparation Of Ion-exchange Resin From Waste Plastics And Its Application In CO₂ Capture

The amount of waste electrical products has enormously increased,due to the increased consumption of electrical products and their relatively short life-cycle.It was reported that waste electrical products were 378 million in china during 2016,including television were 30.6 million.The main components of wasting electrical products include glass,metal and plastic.Plastic accounts for 20-30%of typical solid waste.All these in combination with non-biodegradability of waste plastics,causing serious pollution to the environment.Therefore,improving the recycling rate of waste plastics had become a key issue that needs to be addressed at present.The traditional methods of recycling waste plastics are landfill,incineration,pyrolysis,and gasification et al.However,these methods have disadvantages such as high land occupation rate,water pollution and air pollution.In this paper,macroporous cation exchange resin?MCER?and macroporous cation exchange resin organic amine composite?MCER-DEA?were prepared from waste television crust?WTVC?and applied to the capture of CO₂ in flue gas from coal-fired power plants,it can save resources and protect the environment,and the preparation mechanism and adsorption mechanism of MCER and MCER-DEA were studied on the molecular level by using gauss software.The main research conclusions are as follows.Macroporous cation exchange resin?MCER?were prepared from waste television crust?WTVC?by grafting and swelling-osmosis methods and applied to the capture of CO₂ in flue gas from coal-fired power plants.Fourier transform infrared spectroscopy?FT-IR?and thermogravimetric analysis?TGA?were used to characterize the materials of before and after the reaction,the results showed that the electrophilic substitution occurs in between an H atom of meta position on the benzene ring and H₂SO₄,and a sodium sulfonate resin was successfully prepared.By adding the pore-forming agent n-heptane,ethanol and water,the effects of MCER prepared under different reaction conditions?n-heptane,ethanol/water mass ratios and pore-forming times?on CO₂adsorption capacity were investigated.The results showed that when the amount of pore-forming agent n-heptane was 25 g,the ethanol/water mass ratio was 90/10,and the pore-forming time was 5 h,the equilibrium adsorption capacity of the prepared ion exchange resin for CO₂ reached 1.87 mmol/g.Weber-morris particle diffusion model was used to study the adsorption kinetics,the results showed that the internal diffusion is the rate control step of the CO₂ adsorption process.Macroporous cation exchange resin organic amine composite?MCER-DEA?were prepared from macroporous cation exchange resin?MCER?as the basic framework,diethanolamine?DEA?was grafted to the sulfonic acid group of MCER by grafting method and applied to the capture of CO₂ in flue gas from coal-fired power plants.Fourier transform infrared spectroscopy?FT-IR?and thermogravimetric analysis?TGA?were used to study the reaction mechanism between MCER and diethanolamine?DEA?.The results showed that hydrogen bond and acid base coordination force are formed between MCER and DEA.The effects of MCER-DEA prepared at the addition of different amounts of diethanolamine,different reaction times and reaction temperatures condition on the adsorption capacity of CO₂ were investigated.The results showed that the CO₂ adsorption capacity of MCER-DEA?2.87 mmol/g?were prepared under optimal conditions?9 mL diethanolamine,reaction time 5 h,temperature 70?was much better than MCER?1.87 mmol/g?.The study of adsorption kinetics shows that the adsorption of CO₂ by MCER-DEA is mainly chemisorption adsorption.The preparation mechanism of ion-exchange resin was studied by density functional theory?DFT?and the action mechanism of MCER and MCER-DEA with CO₂ was also studied by quantum chemical calculations.The results showed that the electrophilic substitution occurs in between an H atom of meta position on the benzene ring and H₂SO₄,and a macroporous strongly acidic cation exchange resin?MCER?was prepared.The electron energy of MCER-DEA was calculated to be 1.14 ev,indicating these MCER formed acid-base coordination with diethanolamine?DEA?,and MCER-DEA was prepared successfully.Besides,the electron energy of between MCER and CO₂ is 0.27 ev?1 ev=96.5 kJ/mol?,and the interaction force is dominated by hydrogen bonds,and electron energy of the MCER-DEA and CO₂ is 3.02 ev,the interaction force is mainly controlled by coordination bonds.It further indicates that MCER and CO₂ are primarily based on physical adsorption,while MCER-DEA and CO₂ are mainly chemisorption adsorption.