Journal
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
Volume 471, Issue -, Pages 133-138Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.colsurfa.2015.02.018
Keywords
Adsorption; Mesoporous silica; Functionalized SBA15; Tetracyclines; Complexation
Categories
Funding
- National Science Fund for Distinguished Young Scholars of China [51225805]
- National High Technology Research and Development program of China [2012AA062606]
Ask authors/readers for more resources
The gradual increase of antibiotics in aquatic environments poses a serious threat to human health and ecosystems, and removal technology for antibiotics has attracted great interest in recent years. In this study, to improve the adsorption capacity of mesoporous silica, a new sorbent made by grafting both amino groups and Fe (III) on mesoporous silica SBA15 (named Fe-N,N-SBA15) was prepared and used for the removal of tetracycline antibiotics (TCs) from aqueous solution. The results showed that TCs sorption on Fe-N,N-SBA15 was highly pH-dependent, and the optimal pH was found to be 4.5-5.6 for tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC). The adsorption kinetics fitted the pseudo-second-order model perfectly and the adsorption rate constant followed the order OTC > TC > CTC. The adsorption isotherms study showed the maximum sorption capacity to be 143.31, 96.91 and 69.15 mmol kg(-1) for OTC, TC and CTC, respectively. The differences in the removal trends of the three TCs may be attributed to their different pK(a) values. A thermodynamic study showed that the adsorption of TCs on Fe-N,N-SBA15 is spontaneous (Delta G<0) and endothermic (Delta H>0). FTIR and XPS results showed that the high sorption capacity of antibiotics could be mainly attributed to the complexation of Fe (III) and TCs. (C) 2015 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available