Abstract: In order to study the adsorption properties of lemon residues modified by microwave,the adsorption rates for pb²⁺,specific surface area(BET),ash rate,iodine adsorption value and pore structure of the modified lemon residue were detected,and the structures of lemon residue were characterized by IR,UV,TGDTA,SEM/EDS. Compared to the lemon residue that was treated chemically and pre-treated,the adsorption rates of lemon residue modified by microwave,increased significantly. Compared to chemical treatment,for the lemon residue modified by microwave,the specific surface area decreased,the ash rate increased by nearly 5 times,and the iodine adsorption value increased by nearly 1.5 times,the amount of carboxyl group and lactones group was relatively large,and the amount of lactones group was relatively small. After the modified lemon residue absorbed pb²⁺,the overall framework did not change. Before and after absorbing pb²⁺,the maximum UV absorption peak of the modified lemon residues was about 206 nm and 192 nm,the lemon residue modified by microwave had three weight loss processes,and were mainly composed of carbon. The pb²⁺ can be adsorbed by the modified lemon residues effectively,but the weight and atomic percentage of pb²⁺ were not high. The surface of the modified lemon residues became loose,and the number of holes increased obviously.

Key words: lemon residues, microwave, modification, adsorption