改性酚醛树脂基活性炭对二氯甲烷的吸附

Adadsorption of dichloromethane on modified phenolic resin-based activated carbon

以酚醛树脂为前驱体经过炭化活化制得了酚醛树脂基活性炭(PFAC),分别采用不同金属离子及氨水、磷酸和磷酸氢二铵对PFAC进行改性,并采用BET、SEM、EDS、FTIR、XPS、拉曼光谱、NH_(3)-TPD等技术对活性炭进行表征,考察了其对二氯甲烷的吸附性能。结果表明:不同金属离子改性PFAC对二氯甲烷的吸附能力随表面总酸量和极化率的增大而增加,大小顺序为Fe^(3+)-PFAC>Cu^(2+)-PFAC>Mg^(2+)-PFAC>PFAC;氨水(N)、磷酸(P)和磷酸氢二铵(NP)改性PFAC对二氯甲烷的吸附能力大小顺序为NP-PFAC>N-PFAC>P-PFAC>PFAC,磷酸和磷酸氢二铵的改性有助于提高PFAC比表面积,氨水和磷酸氢二铵改性可使PFAC吸附位点增加;NP-PFAC具有较好的再生吸附能力。

Phenolic resin-based activated carbon(PFAC)was prepared by carbonization activation using phenolic resin as precursor,and modified using different metal ion,ammonia,phosphoric acid and diammonium phosphate,respectively.The products were characterized by BET,SEM,EDS,FTIR,XPS,Raman and NH_(3)-TPD,etc.,and their adsorption capabilities for dichloromethane were investigated.The results show that:The adsorption capability of different metal ions-modified PFAC for dichloromethane increases with the total acidity and polarization rate on PFAC surface with the order of Fe^(3+)-PFAC>Cu^(2+)-PFAC>Mg^(2+)-PFAC>PFAC;The adsorption capacity of PFAC modified by ammonia(N),phosphoric acid(P)and diammonium phosphate(NP)for dichloromethane follows the order of NP-PFAC>N-PFAC>P-PFAC>PFAC.The modification with phosphoric acid and diammonium phosphate helps to increase the specific surface area of PFAC,while the modification with ammonia and diammonium phosphate can increase the adsorption sites of PFAC;In addition,NP-PFAC shows a good regenerative adsorption capability.