椰壳活性炭复合改性及其对模拟烟气中CO_2的吸附性能  

Study of the multiple modification of cocoanut activated carbon and its adsorption properties of CO_2 in simulated flue gas

作　　者：林小英[1,2] 张惠云[1] 刘亚敏[2] 江梅[2] 刘明华[3] 白生杰 林诚[1] 

机构地区：[1]福州大学石油化工学院,福州350116 [2]福建工程学院生态环境与城市建设学院,福州350118 [3]福州大学环境与资源学院,福州350116

出　　处：《功能材料》2015年第17期17017-17021,共5页Journal of Functional Materials

基　　金：福建省教育厅资助项目(JK2013032);福建省科技厅资助项目(2008F5002)

摘　　要：以椰壳活性炭为载体,进行HNO3＋TEPA复合改性和KOH＋TEPA 复合改性,并考察活性炭复合改性前后对模拟烟气中CO2 的吸附性能,结果表明,KOH＋TEPA 复合改性后吸附性能提高,HNO3＋TEPA 复合改性后吸附性能降低.KOH＋TEPA复合改性后的活性炭（OH-TEPA-AC）在303K 条件下,对模拟烟气（10%（体积分数）CO2,90%（体积分数）N2）中CO2 的静态吸附量从改性前的0.670mmol/g提高到1.182 mmol/g.在303K 条件下,活性炭OH-TEPA-AC对模拟烟气中CO2 的动态吸附量稳定在0.970-1.152mmol/g间,对引入水分的烟气中CO2的吸附量稳定在1.192-1.215mmol/g间,表现出良好的循环吸附性能及对水分的稳定性.动力学分析表明,OH-TEPA-AC对模拟烟气中CO2 的平均吸附热值为-52.0kJ/mol,保证了工业实际应用的经济性.Porous cocoanut activated carbon was modified using tree chemical methods:tetraethylenepentamine(TEPA)modified directly(AC),firstly oxidized by HNO3solution(10%)for 4hat 353 Kthen TEPA modified(HNO3+TEPA)and firstly alkalified by KOH solution(5mol/L)for 4hat 353 Kthen TEPA modified(KOH+TEPA).The results show that KOH reduction on AC improved the effect of the modification,HNO3 oxidation on AC has no significant effect on modification.The CO2 adsorption capacity of OH-TEPA-AC measured using a thermogravimetric analyzer(TGA)in simulated flue gas conditions(10vol% CO2,90vol% N2)was about1.182mmol/g at 303 K,the dynamic adsorption capacity was between 1.192-1.215 and 0.970-1.152mmol/g with or without the presence of water during ten cycles of adsorption/desorption.Dynamics analysis shows that the average isosteric heat of adsorption was about-52kJ/mol,so OH-TEPA-AC was likely to be satisfactory in practical applications of capturing CO2.

关 键 词：椰壳活性炭 复合改性 KOH+TEPA HNO3+TEPA CO2吸附 

分 类 号：TQ424.1[化学工程]