Preparation of activated carbon from spent catalyst with mercury by microwave-induced CO2 activation

This study reported the regeneration of mercury-loaded porous carbon catalyst utilized in the manufacture of PVC (Polyvinyl chloride) resin using the combined effect of microwave heating and CO2 purging. The porosity, functional, and surface chemistry was featured by means of low-temperature nitrogen adsorption, scanning electron microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The result showed that the iodine number, methylene blue adsorption, and yield of FMC were 791.64 mg/g, 270 mg/g, and 84.2%, respectively, under the best conditions. Additionally, the mercury removal rates were above 99.5% at different temperatures. The regenerated samples at different temperatures were characterized to assess their physical binding capability and chemisorption abilities, which further revealed the impact of regeneration temperature on the improvement in the porosity of the regenerated catalyst. The findings revealed the potential of microwave heating for the regeneration of FMCs.