Location and size regulation of manganese oxides within mesoporous silica for enhanced antibiotic degradation

Refractory antibiotics in domestic wastewater are hard to be completely eliminated by conventional methods, and then lead to severe environmental contamination and adverse effects on public health. In present work, advanced oxidation processes (AOPs) are adopted to remove the antibiotic of sulfachloropyridazine (SCP). Nanosized Mn2O3 was fabricated on the SBA-15 material to catalytically activate potassium peroxydisulfate (PDS) to generate reactive oxygen radicals of center dot OH and SO4?????? for SCP degradation. The effects of location and size of Mn2O3 were explored through choosing either the asmade or template-free SBA-15 as the precursor of substrate. Great influences from the site and size of Mn2O3 on the oxidation activity were discovered. It was found that Mn2O3 with a large size at the exterior of SBA-15 (Mn-tfSBA) was slightly easier to degrade SCP at a low manganese loading of 1.0-2.0 mmol center dot g 1; however, complete SCP removal could only be achieved on the catalyst of Mn2O3 with a refined size at the interior of SBA-15 (Mn-asSBA). Moreover, the SO4???- species were revealed to be the decisive radicals in the SCP degradation processes. Exploring the as-made mesoporous silica as a support provides a new idea for the further development of environmentally friendly catalysts. (c) 2021 Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

Automated summary

Refractory antibiotics in domestic wastewater are difficult to eliminate completely using conventional methods, leading to environmental contamination and negative impacts on public health. This study utilized advanced oxidation processes (AOPs) to remove sulfachloropyridazine (SCP) antibiotics. Nanosized Mn2O3 catalysts were synthesized on SBA-15 material to activate potassium peroxydisulfate (PDS) and generate reactive oxygen radicals for SCP degradation. The location and size of Mn2O3 were found to significantly influence the oxidation activity, with Mn2O3 at the interior of SBA-15 showing complete SCP removal. The study also revealed the importance of SO4???- species as decisive radicals in the SCP degradation processes. Exploring the use of as-made mesoporous silica as a support provides new insights for the development of environmentally friendly catalysts.