A carbonized cobalt catalyst supported by acid-activated clay for the selective hydrogenation of acetylene

Abstract

This study focused on the purification of ethylene from acetylene using a catalyst made of cobalt deposited on a carbon-containing material, such as clay. Cobalt catalysts with different mass fractions were carbonized at a temperature of 550 °C, activated with 5% and 10% nitric acid and tested for the hydrogenation of acetylene to ethylene. The physicochemical properties were investigated by means of X-ray powder diffraction (XRD), scanning electron microscope (SEM) and TG/DSC. The reaction products were analyzed using a Chrom-3700 gas chromatograph and gas chromatography–mass spectrometry (Agilent 7890A/5975C). The conversion of a 7% Co/CL-10 catalyst, carbonized at 550 °C, was 82% at 100 °C, and reached 95% at 140 °C. Side reactions were activated when the temperature rose above 140 °C, which reduced the ethylene yield. The carbonized catalysts exhibited more activity than traditional impregnated catalysts that had not been subjected to carbonization. This paper outlines a simple method for preparing Co/CL-10 catalysts with high catalytic activities for the selective hydrogenation of acetylene, using the carbonization process on a chemically-activated carrier clay.