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Based on the characteristics of typical C9 + aromatics in naphtha fractions, the effects of key process parameters and heavy aromatic composition on product distribution of fluid catalytic cracking (FCC) of heavy aromatics (HAs) were investigated. The results show that catalysts with large pore size and strong acid sites are favorable for the conversion of HAs to benzene–toluene–xylene (BTX) at higher reaction temperatures and moderate catalyst–oil ratios (C/O). With a Y zeolite-based catalyst which was hydrothermally pretreated for 4 h, the conversion of Feed 1 at 600 °C and C/O of 10 may reach 64.93%. Meanwhile, the yield and selectivity of BTX are 34.80 and 53.61%, respectively. The proportion of BTX can be adjusted within a certain range. The HAs from different sources show high conversion and good BTX selectivity, which provides strong support for the technological development of HAs to light aromatics in FCC operation.

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Methyl acetate (MA) has a wide range of applications as an important industrial chemical. Traditional MOR zeolite for carbonylation of DME to MA accumulated carbon easily because of a 12-membered ring (12 MR) channel. In this work, we innovatively developed the method of recrystallization ferrierite (FER) zeolite using special chelating ligand sodium oleate which can affect ions other than alkali metals. The characterization results of N2 adsorption, transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) show that hydrothermal recrystallization of ferrierite using sodium oleate resulted in a higher Si/Al ratio, a bigger specific surface area and a larger number of Brønsted acid sites in the eight MR channels, which was more efficient in the reaction of carbonylation of dimethyl ether than ordinary alkali treatment.

Highly efficient and stable catalysts are among the key factors in industrial ethanol dehydration to ethylene. Among the widely studied catalysts, alumina is the most suitable for industrial application. In this study, novel gamma alumina was synthesized by solvent protection and a hydrothermal procedure. HRTEM, XRD, FT-IR, NH3-TPD, H-D exchange, and 29Si MAS NMR were employed to compare the difference in physicochemical properties between the novel gamma alumina and commercial alumina. Characterization results show that the as-synthesized novel gamma alumina mainly exposes the high-energy crystal plane (111) while the commercial alumina mainly exposes the thermostatically stable (110) crystal plane. The dominating (111) plane, according to the characterizations, endows the novel gamma alumina with a higher density of surface hydroxyl groups, higher acid content, and higher surface energy compared to the commercial alumina. The catalytic performance of the two catalysts for industrial ethanol dehydration to ethylene was studied. The novel (111) plane-exposed alumina showed a higher yield of ethylene than commercial alumina under the same reaction conditions. This could be related to the difference in atomic arrangement and the unsaturated aluminum coordination of different crystal planes. Stability testing under severe reaction conditions (450 °C, 1 MPa, 4 h−1) indicates that novel gamma alumina shows better stability (catalyst life cycle increased by 50%) and produces less acetaldehyde as a byproduct. The effects of steam treatment on the catalytic performance were further investigated. The surface acidity and the catalytic performance of novel gamma alumina present a volcanic curve with the increase in steam treatment temperature. Under the optimal water vapor treatment temperature of 650 °C, the conversion of ethanol and selectivity of ethylene were both higher than 99%.