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Spherical carbonaceous solid catalysts with -SO 3 H group are prepared by hydrothermal carbonization of starch followed by carbonization at low temperatures and sulfonation with H 2 SO 4 . The concentration of introduced -SO 3 H is determined by the amount of polar groups on carbon materials surface, and a high -SO 3 H group concentration (2.15 mmol g À1 ) is achieved. The spherical carbonaceous solid acid is evaluated as catalysts for the condensation of 2,4,5-triphenyl-imidazole under free solvent. Remarkably high 2,4,5-triphenyl-imidazole yields (93 %) can be obtained efficiently (110 o C and 90 min) when HTS-400-SO 3 H was used as catalyst. The catalytic activity is determined by the acid concentration of carbonaceous solid surface. There is slight decrease in catalytic activity of HTS-400-SO 3 H after five runs. The starch-derived catalysts can be easily recovered by simple filtration and exhibited high activity for ten successive recycles.[a] Dr.

To efficiently utilize the catalyst active sites and simultaneously enhance target hydrocarbon selectivity in Fischer-Tropsch synthesis (FTS), herein, we demonstrate a promising Co-Al 2 O 3 hollow-sphere catalyst prepared by a two-pot route including hydrothermal carbonization and wet impregnation. Benefiting by plentiful mesopores on the shell, reactants could access the cavity inside and the active sites on the inner surface for further FTS reaction. Compared with conventional solid catalyst, the hollow structure provided a "buffer-pot" effect, where feed gas and preliminary product from the shell could mix completely at a low flow rate. Heavy hydrocarbons were further confined, leading to enhanced formation of lighter C 5 -C 11 components, which more readily escaped out through the mesoporous shell, which thus played a "filter" role. Additionally, increased acidity on the shell generated more isoparaffins and olefins in the final product. This concept displayed a great superiority in improving active metal activity and selective production from multiple products compared with conventional supported catalysts.

A two-step method consisting of acid leaching and base leaching was developed and applied to create hierarchical pores on a general microporous Y zeolite. Characterization with BET and TEM on the texture, morphology and structure of the prepared hierarchical Y zeolite confirmed the coexistence of mesopores with zeolitic walls. The analysis results showed that the mesopore surface area and pore volume of the hierarchical zeolite Y (Y-ABx, A: acid leaching, B: base leaching, "x" represents for base leaching time) increased with increasing the base leaching time. The hierarchical zeolite Y supported Co as catalysts were employed to catalyze the hydrogenation of carbon monoxide to form hydrocarbons through Fischer-Tropsch synthesis (FTS) reaction. The CO conversion and C 5-11 selectivity on Co/Y-ABx catalysts increased significantly compared with those on the pristine Y supported Co catalyst. The isoparaffin selectivity of Co/Y-AB4 catalyst reached up to 52.3 % and middle hydrocarbons became the main FTS products due to the optimized hydrocracking and isomerization function afforded by the hierarchical zeolite Y with the strong Brønsted acid/Lewis acid (B/L) ratio and textural property.