Sorption of antibiotics onto montmorillonite and kaolinite: competition modelling

Abstract

Antibiotic contaminants, which are generally present in bi-solute systems, can be competitively adsorbed onto clays. Single- and bi-solute sorptions of sulfadiazine (SDZ) and ciprofloxacin (CIP) onto montmorillonite and kaolinite were investigated at pH values of 5 and 8. Freundlich and Langmuir models were used and fit the experimental data well for single-solute sorption. The sorption isotherms were nonlinear (N = 0.265-0.730), and the maximum sorption capacities (q) of the SDZ and CIP onto montmorillonite were higher than those onto kaolinite. The octanol-water distribution ratio (D), cation exchange capacity (CEC), Brunauer-Emmett-Teller (BET) surface area (A), pore size, point of zero charge (pH), and basal spacing predominantly affected the Freundlich constant (K) and q of SDZ and CIP at pH 5 more than SDZ and CIP at pH 8. For bi-solute sorption, the presence of CIP inhibited the SDZ sorption onto montmorillonite and kaolinite. Competitive sorption models such as Sheindorf-Rebhun-Sheintuch (SRS), Murali-Aylmore (M-A) and the modified extended Langmuir model (MELM) were used; of these, the MELM provided the best prediction with SDZ sorption onto montmorillonite at pH 8 and CIP onto kaolinite at pH 5 and 8 in SDZ/CIP system occurring synergistically, whereas others occurred antagonistically. The distribution coefficient (K) of the bi-solute sorption decreased with increasing pH in the order cationic > neutral > anionic for SDZ and cationic > zwitterionic > anionic for CIP, which resembled the K of single-solute sorption. Fourier transform infrared spectroscopy (FT-IR) spectra indicated that amine in SDZ and keto oxygen in CIP were responsible for the interactions with the montmorillonite and kaolinite.

Spectrophotometric and nucleic acid-binding properties of halloysite clay nanotubes and kaolinite

“…A previous study by Gupta et al demonstrated that metals bind relatively poorly to kaolinite [ 59 ], which may explain, in part, the weaker impact of Mg 2+ and Ca 2+ ions on binding to this clay. In addition, the results of the gas sorption analysis presented here and some past studies of the clay point to a more general reduced surface area adsorption capability among kaolinite nanoparticles ( Table 1 ) [ 40 , [60] , [61] , [62] , [63] ]. Interestingly, the limited natural adsorption capacity of kaolinite has been improved by synthetic conversion into cylinders and microspheres, structures with interior spaces analogous to HNT [ 64 , 65 ].…”

“…HNT has been used as a natural vehicle for microencapsulation and controlled release of nucleic acids as well as both lipophilic and hydrophilic drugs [ [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] ]. In addition, clays such as HNT and kaolinite have the ability to adsorb/remove heavy metals and industrial chemicals [ [40] , [41] , [42] , [43] ].…”

The Influence of Groundwater Desalination by Modified Active Carbon/Bentonite on Its Application in Agriculture

“…The bentonite was found to be pure because of the spectra. The peaks of X-ray diffraction were compared to the well-known clay minerals literature [27]. The elemental analysis of bentonite was also determined using SEM/EDAX.…”

SBR Sisteminin Antibiyotik (Tetrasiklin/klortetrasiklin) ve Ağrı Kesici (Parasetamol) Varlığında Nitrifikasyon ve Denitrifikasyon Performansının Belirlenmesi

“…Topraktaki emilimlerinin düşük olması sebebiyle de yeraltı sularına veya diğer kaynaklara hızlıca ulaşabilirler. Çevreye salındığında sudaki çözünürlüğünün yüksek olması sebebiyle de kolayca yüzey sularına ulaşabilirler [7]. Tetrasiklinler (TC) birçok bakteriyal enfeksiyonun tedavisi için önemli farmasötik antibiyotikler olup, hayvan hastalıklarını tedavi etmek ve hayvanların büyümelerini hızlandırmak için hayvansal gıdalara eklenebilmektedir.…”