Preparation Of Several New Porous Carbon Materials And Their Adsorption And Separation Performance For C₂H₆/C₂H₄ And C1-C3

Energy conservation and emission reduction are major demands for sustainable development of human society.Light hydrocarbon separation is a typical energy-intensive separation process in the petrochemical industry.In this work,aiming to separate C₂H₆/C₂H₄and C1-C3 effectively under ambient condition,starch and fructose were used as raw materials to prepare several novel porous activated carbon materials and their adsorption and separation performance of C₂H₆/C₂H₄ as well as C1-C3 mixture were investigated.New pore structure adjustment strategies of carbon materials were explored,which provides new basis for application.The reserach topic has values for both theoretical research and practical utilization.In this paper,starch-based and fructose-based carbon materials were prepared and their light hydrocarbon adsorption and separation properties were studied.With specific surface area of 2097 m²/g and micropore volume of 0.8 cm³/g,fructose-based carbon material Fru-4-700 preferentially adsorbed C₂H₆.The adsorption capacity of C₂H₆ was as high as 7.94mmol/g?25oC,100 kPa?on Fru-4-700.The selectivity of C₂H₆/C₂H₄ on Fru-4-700 was between 1.6-4,predicted by IAST.The specific surface area of starch-based carbon material SK-1 reached 1154 m²/g,and the pore volume of micropores was 0.39 cm³/g.SK-1 has excellent adsorption and separation performance for C1/C2/C3 mixtures.Its adsorption capacity of CH₄,C₂H₆ and C₃H₈ at ambient condition were 1.87,4.98 and 4.71 mmol/g respectively.The IAST selectivity of C₂H₆/CH₄ and C₃H₈/CH₄ were as high as 30.1 and 328.It is one of the porous materilas with the highest selectivety at present.In this paper,starch-based carbon materials were prepared by CO₂ activation,and their adsorption and separation performance for C₂H₆/C₂H₄ were investigated.SC-Y preferentially adsorbed C₂H₆.At 25oC and 100 kPa,C₂H₆ and C₂H₄ adsorption amounts on SC-975 reached6.23 and 5.18 mmol/g respectively.The IAST selectivity ranged from 4.66 to 1.65.In this paper,the pore structure adjustment approach of carbon-based materials was studied and its effect for C₂H₆/C₂H₄ adsorption and separation was discussed.Herein,three strategies of reactivation and one strategy of CO₂/N₂ gas mixture activation for pore structure adjustment were proposed.The result shows that the pore size distribution of materials is generally determined by the first pore-forming process,and the pore volume can be effectively increased by the mild reactivation within controllable pore size distribution.Reacivated under 900oC with CO₂ is a mild adjustment method,which can increase both narrow pore?<1 nm?volume and micropore volume.Pores which size less than 1nm were conducive to improving the adsorption capacity at low pressure.