The Preparation of Copper–Manganese Catalysts Using a Sequentially Feeding Microreactor

Abstract

The Cu–Mn interaction in copper–manganese composite oxide catalysts is crucial for their catalytic oxidation activity of volatile organic compounds (VOCs). In this study, highly dispersed copper–manganese coprecipitates were synthesized using a microreactor, and the effects of feeding intervals on the structure of the precipitates and catalysts were investigated by means of X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The results indicate that sequential feeding can produce coprecipitates with better uniformity. An appropriate time difference between the Mn²⁺ and Cu²⁺ feeds can make the coprecipitate more uniform and enhance the Cu–Mn interactions in the catalyst. Higher ratios of both surface Mn³⁺/Mn⁴⁺ and O_latt/O_ads are considered attributable to better catalytic performance.