[Sorption and desorption of phenanthrene by organo-mineral complexes with different bridge cations].
Sorption and desorption of phenanthrene by organo-mineral complexes with Ca2+, Fe3+ and Al3+ as bridge cations were studied according to the association type between organic matter and minerals in natural soils. The results showed that the data of phenanthrene sorption and desorption by different cation saturated montmorillonite and their corresponding humic acid and mineral complexes could be fitted with Freundlich model, and the order of the sorption capacities (Kf) were Ca-Mont (0.184) > Fe-Mont (0.028) > Al-Mont (0.015) and Fe-Mont-HA (2.341) > Ca-Mont-HA (1.557) > Al-Mont-HA (1.136), respectively. The Kf values of humic acid and mineral complexes were far greater than those of minerals, which demonstrated that humic acid made great contributions to the sorption of phenanthrene in the organo-mineral complexes. However, the Kf values of the organo-mineral complexes with different bridge cations were not consistent with their organic carbon content, which indicated that both the organic carbon content and the combined types between organic matter and mineral could affect the sorption capacity of phenanthrene by the organo-mineral complexes. The desorption hysteresis of phenanthrene was significant for Ca2+ and Al3+ bridged organo-mineral complexes. Desorption hysteresis of phenanthrene was mainly from the sorption of phenanthrene by organic matter, and the contributions of mineral to the desorption hysteresis were not significant.
Ni
Jin-zhi
JZ
Soil and Environment Bioremediation Research Centre, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. nijz@fjnu.edu.cn
Luo
Yong-ming
YM
Wei
Ran
R
Li
Xiu-hua
XH
Qian
Wei
W
D000327:Adsorption; D000535:Aluminum / Q000737:chemistry; D001546:Bentonite / Q000737:chemistry*; D002118:Calcium / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D008903:Minerals / Q000737:chemistry*; D010616:Phenanthrenes / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*
D002412:Cations; D008903:Minerals; D010616:Phenanthrenes; D012989:Soil Pollutants; D001546:Bentonite; C031181:phenanthrene; D000535:Aluminum; D007501:Iron; D002118:Calcium