Novel sodium percarbonate/gallic acid/Fe doped MnO2 catalyst effervescent tablets for efficient degradation of amoxicillin

Abstract

In this work, Fe-loaded MnO₂ (Fe@MnO₂) nanomaterials were co-pressed with gallic acid (GA) and sodium percarbonate (SPC) to form a composite effervescent tablet (G-S-MOFO-ET) for the efficient degradation of antibiotics. The modulation of GA accelerated the Fe/Mn cycling on the catalyst surface while making the effervescent tablet system excellent in degradation, cyclic stability and resistance to environmental interference. About 95 % amoxicillin (AMX) could be degraded within 3 min (k_obs = 0.0157 min⁻¹). Density functional theory (DFT) calculations indicated that the introduction of Fe sites realized the transfer of the catalyst active sites from Mn to Fe, resulting in the formation of a degradation system dominated by ·O₂^•− and assisted by HO^• and ¹O₂. In addition, the micron bubbles generated by the self-aeration of the effervescent tablet significantly enhanced the mass transfer efficiency of the system, which is equivalent to magnetic stirring at 50 r/min and has a promising future in engineering applications.