THE SORPTION OF OFLOXACIN BY HYDRATED ALUMINA AND SILICON

Abstract

The sorption of ofloxacin (OFL) – the antibiotic from class of fluoroquinolones has been studied on alumina (γ-Al2O3) different acid-base modifications – acidic Al2O3(acidic), neutral Al2O3 (Neutral) and the basic Al2O3 (core) and amorphous silica – silica gel (SG ) L 5/40 and aerosil A-300. Determination of ofloxacin in solutions has been carried out by spectrophotometry on spectrophotometer SF-46 at λ = 291 nm and acidity 7. To clarify the nature of the sorption surfaces of OFL hydrated on aluminum and silicon oxides were studied according to the degree of extraction (S%) from pH, contact time of the phases (min.) sample from the sorbent mass (g); sorption isotherms were built and antibiotic desorption was studied. The OFL significant recovery (~ 60%) is observed at the pH range of 4 ÷ 8, and reaches its maximum (80-85%) at pH 7. The maximum degree of extraction of the antibiotic on aerosil A-300 and L 5/40 silica realized at pH 6 and it was ~ 80%. Comparative analysis of the forms constructed isotherms (L – type) indicates a significant affinity investigated hydrated oxides to sorbate. The value of the static exchange capacity and concentration ratios can proof that. Differences in the quantitative characteristics of sorption of aluminum and silicon oxides are associated with nature and the acid-base properties of adsorption sites. In the study of the OFL concentrates desorption in static mode dilute NaOH and HNO3 solutions it was found that growth desorption degree occured with increasing concentration. Desorption was 2-3 times better in the case of aluminum oxide than silicon oxide when there were the same concentrations of acid and alkali. This is another confirmation of the participation in various sorption interactions forces of physical and chemical nature.

Keywords

• антибіотики
• офлоксацин
• оксиди алюмінію і силіцію
• сорбція
• десорбція