Preparation of Mn-Co-MCM-41 Molecular Sieve with Thermosensitive Template and Its Degradation Performance for Rhodamine B

Abstract

Rhodamine B (RhB) in dyes is widely used in various industries, but it poses a great threat to the natural environment and human health. In this work, a series of thermosensitive polymer materials, PNxDy, with controllable morphology and particle size were prepared by free radical polymerization using N-isopropylacrylamide and N,N-dimethylacrylamide as monomers. Then, by using PNxDy as a template, bimetallic Mn- and Co-doped MCM-41 molecular sieves with good morphology and properties were prepared by the microwave-assisted hydrothermal method. The effects of a series of thermosensitive templates on the morphology and properties of the Mn-Co-MCM-41 molecular sieve were investigated. The results demonstrated that the Mn-Co-MCM-41 by PN100D4 as a templating agent showed the best mesoporous ordering and the most regular material morphology with 2 nm nanoparticles. In addition, the molecular sieve with the best structure was selected for the RhB degradation experiments. The Mn-Co-MCM-41 with PN100D4 as the template showed regular morphology and uniform pore channels. It was applied as a catalyst for the degradation of RhB by potassium monopersulfate (PMS). The degradation rate of RhB could reach 98% with a 20 min reaction by Mn-Co-MCM-41 (PN100D4). Meanwhile, the degradation rate could be maintained at 91% after being reused six times. The bimetallic-doped Mn-Co-MCM-41 molecular sieves prepared using the thermosensitive material PN100D4 as a template have good catalytic performance and can be effectively reused.