ABSTRACT
The interaction of oil shale, as a widespread sedimentary rock, with common antibiotics ofloxacine, oxytetracycline, and ciprofloxacine was studied. The selected Moroccan deposit and its thermally treated forms were fully characterized from a chemical and structural point of view, indicating the prevalence of quartz as a mineral component together with aluminum- and iron-rich phase that are converted into Al-doped iron oxide phases upon heating. The presence of 4 wt% organics was also detected, which was removed at 550 °C without significant loss of specific surface area. The pseudo-second-order kinetic model and Langmuir equation were found the most adequate to reproduce the kinetics and isothermal sorption experiments. These analyses enlighten the contribution of the organic matter on antibiotic retention as well as the key role of hydrophobic interactions on the molecule-mineral surface interactions. Our results emphasize the possible contribution of raw oil shale in the accumulation of antibiotics in soils and suggest that thermally treated oil shell powders can constitute cheap mineral sorbents for environmental cleaning.
Subject(s)
Anti-Bacterial Agents/chemistry , Environmental Restoration and Remediation/methods , Minerals/chemistry , Soil Pollutants/chemistry , Adsorption , Anti-Bacterial Agents/analysis , Ciprofloxacin/analysis , Ciprofloxacin/chemistry , Hydrophobic and Hydrophilic Interactions , Minerals/analysis , Morocco , Ofloxacin/analysis , Ofloxacin/chemistry , Oxytetracycline/analysis , Oxytetracycline/chemistry , Powders/analysis , Powders/chemistry , Soil Pollutants/analysisABSTRACT
Organofunctionalized apatite nanoparticles were prepared using a one step process involving dissolution/precipitation of natural phosphate rock and covalent grafting of nitrilotris(methylene)triphosphonate (NTP). The synthesized materials were characterized by Brunauer-Emmett-Teller (BET) surface measurement, thermogravimetry, inductively coupled plasma emission spectroscopy (ICP-ES), elemental analysis, multinuclear solid state cross-polarization/magic angle spinning (CP/MAS) and single-pulse NMR spectroscopy, transmission electron microscopy (TEM) and energy dispersive x-ray analysis (EDXA). After grafting BET measurements yielded particle specific surface areas ranging from 88 to 193 m(2) g(-1) depending on the grafted phosphonate. The results show that the surfaces of the nanoapatite particles can be covered with functional groups bound through a variable number of R-P-O-Ca bonds to render them organoapatites.
