沥青基球形活性炭对CO_2的吸脱附行为研究

Adsorption/Desorption Performance of CO_2 on Pitch-based Spherical Activated Carbons

考察了沥青基球形活性炭(PSAC)的孔结构与CO2吸附容量间的内在关系及其脱附性能.采用N2吸附法分析PSAC的孔结构,由穿透曲线测试其对CO2的平衡吸附量.实验结果表明:在CO2/N2混合气氛下,活性炭对CO2的吸附容量与孔径小于1nm的微孔比表面积呈线性关系;当PSAC担载5%的三聚氰胺后,对CO2(15%)的平衡吸附量由0.91mmol/g增加到1.15mmol/g,提高了26.3%;采用抽真空脱附时,循环脱附效率为74.6%,而电解吸-抽真空耦合脱附工艺可使CO2的循环脱附效率接近100%.

The relationship between the pore structure parameter of pitch-based spherical activated carbons（PSACs） and adsorption capacity of CO2 was investigated as well as the desorption performance.The pore structure characteristics of PSACs were analyzed by nitrogen adsorption at 77K and the equilibrium adsorption amount of CO2 was determined through the breakthrough curve.The results indicated that there was a linear re-lationship between the equilibrium adsorption amount of CO2 and the specific surface area of micropores with pore size smaller than 1 nm.When 5% melamine was coated on the surface of PSAC,the equilibrium adsorption amount of CO2 increased 26.3% from 0.91 mmol/g to 1.15 mmol/g.The desorption cycle efficiency of CO2 is 74.6% with Vacuum Swing Adsorption（VSA）,while it can reach 100% with combined Electric Swing Adsorp-tion（ESA） and VSA.