Effects of Natural Dolomite Catalysts on Cracking Anthracene Oil

Natural dolomite catalysts, representing a cheap and environmentally friendly alternative to nickel-based compounds, can be used for the cracking of anthracene oil to form more valuable products. The impact of operating conditions (temperature, water/oil mass ratio, and space velocity) on the distribution and yield of pyrolysis products was investigated in a fixed-bed reactor, providing insights into the mechanism of cracking. The gaseous products were analyzed by gas chromatography; the catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy; and the pyrolysis oil was analyzed by gas chromatography–mass spectrometry. The obtained results revealed that the gaseous products comprised H 2, CO, CO 2, CH 4, and C 2 +. In comparison to anthracene oil, the pyrolysis oil contained significantly decreased amounts of alkyl aromatic hydrocarbons and indene compounds as well as an increased content of polycyclic aromatic hydrocarbons, such as naphthalene and phenanthrene. XRD and SEM analyses revealed granular coke deposition on the catalyst surface at a high temperature accompanied by partial conversion of the catalyst to CaCO 3, which could be mitigated using high water/oil ratios. Thus, this study demonstrated the influence of reaction conditions on natural-dolomite-catalyzed cracking of anthracene oil, which is important for optimizing industrial production processes.