Catalytic cracking of tar component from high-temperature fuel gas

The cracking removal of tar component in high-temperature fuel gas cleanup is one of the most crucial problems in developing cleanest advanced power technology. Five catalysts were evaluated to tar component removal from high-temperature fuel gas in a fixed-bed reactor. 1-Methylnaphthalene was chosen as a model of tar component. The Y-zeolite and NiMo catalysts were found to be the most effective catalysts. Two catalysts almost removed 100% tar component at 550 °C. The process variables, temperature and space velocity, have very significant effects on tar component removal with catalysts. The long-term durability shows that two catalysts maintain more than 95% removal conversion at 550 °C in 168 h. The combustion study of coke deposited on catalysts by thermal gravimetric analysis technology shows that very small amount buildup of coke appears on two catalysts surface. Using a first-order kinetic model, the apparent energies of activation and pre-exponential factors for tar component removal reaction and coke combustion on catalysts were obtained for the most active catalysts.

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