Template-free Hydrothermal Synthesis of Hollow Alumina Microspheres and Its Excellent Catalytic Properties for Thiolation

In view of the important industrial application value of alumina supports in the field of oil refining and reforming, it is of great significance to develop a simple and economical synthesis method for the hier-archical porous alumina. Herein, the hollow microsphere alumina was hydrothermally synthesized with -out template. The surface of the hollow microsphere alumina supports has a raised fluffy structure, the microsphere diameter is about 5 ti 8 lm, and the thickness of the shell is about 1 lm. The morphology evolution process from solid microspheres to core-shell microspheres with spindle-shaped nanoclusters, and then to hollow fluffy microspheres with protruding surface was observed by investigating the effect of hydrothermal synthesis temperature on the morphology of microspheres. Because of its specific mor-phology and surface characteristics, the microsphere can better disperse the active component KW to prepare KW/Al2O3 catalyst and used in the thiolation to methyl mercaptan. Compared with our previ-ously used catalysts prepared from commercial alumina, this KW/Al2O3 catalyst was not only able to greatly reduce the amount of active component, but also exhibited higher CH3SH selectivity. On the 10KW/Al catalyst, the CH3SH selectivity reached 66.2 % at 340 degrees C, which was about 10 % higher than that of the previous commercial alumina catalyst. This work can provide theoretical basis and practical guid-ance for the reasonable design of new alumina support and high efficiency methyl mercaptan catalyst.(c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.