GUO Xiao-jing,ZHANG Zhi-yi,GUO Zhang-zhen,et al.Absorption Behavior of Cadmium in Aqueous Solution by DDTC Modified Magnetic Nano-Fe3O4[J].China Water & Wastewater,2021,37(9 9):57-64.
Absorption Behavior of Cadmium in Aqueous Solution by DDTC Modified Magnetic Nano-Fe3O4
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
9 9
Page:
57-64
Column:
Date of publication:
2021-05-01
- Keywords:
- sodium diethyldithiocarbamate; magnetic nanomaterial; Fe3O4; cadmium; adsorption; modification
- Abstract:
- A novel adsorbent (DDTC-MNPs) was prepared by modifying magnetic nano-Fe3O4 with sodium diethyldithiocarbamate (DDTC), which was employed to adsorb heavy metal Cd2+. The properties of DDTC-MNPs were characterized by SEM, XRD, FTIR and TG, and Cd2+ adsorption capacity of the material was investigated by batch adsorption experiments. The results showed that the particle size of DDTC-MNPs was about 20 nm. The removal efficiency of Cd2+ by DDTC-MNPs increased with the increase of pH, and effective adsorption was achieved in a wide range of pH (3.0-7.0). The presence of K+，Na+，Ca2+ and Mg2+ had a certain impact on the adsorption of Cd2+，but it could still keep good adsorption effect. Adsorption kinetics showed that the adsorption of Cd2+ by DDTC-MNPs reached equilibrium within 10 min, which was in line with the pseudo-second-order model. Isothermal adsorption conformed to the Langmuir model (R2>0.97) with the maximum theoretical adsorption capacity of 21.74 mg/g, indicating that the adsorption was a monolayer chemical adsorption. The Cd2+ adsorption thermodynamic parameters of DDTC-MNPs, namely ΔG0, ΔH0 and ΔS0, were all less than zero, indicating that the adsorption reaction was spontaneous thermal reaction. The removal efficiency of Cd2+ was still larger than 70% after four times of adsorption and desorption.
Last Update:
2021-05-01