Potassium-catalyzed petroleum coke gasification activity with steam and H2 production characteristics
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摘要: 在固定床反应器中考察了钾盐对金山石油焦/水蒸气气化反应活性和产氢特性的影响,并与石油焦/水蒸气非催化气化反应特性进行了对比研究。研究结果表明,钾盐不仅能有效降低气化反应温度、改善石油焦的气化反应活性,而且能够促进气化反应过程中发生的各种反应(碳/水反应、水煤气变换和甲烷/水蒸气重整反应)。随着气化温度的升高,非催化气化的产物气中H2的含量逐渐增加,而催化气化的产物气中H2的含量则有所降低,这是由于非催化和催化气化条件下水煤气变换反应处于不同的状态。与非催化气化相比,催化气化条件下单位质量石油焦完全气化生成的产物气中H2不仅产率高,而且含量也高(非催化和催化气化条件下H2的含量分别为47.2%~54.1%和55.0%~60.4%)。各种钾盐对石油焦/水蒸气气化反应的催化活性顺序为:K2CO3>KAc>KNO3>K2SO4>KCl,但不同的钾盐对气体产物分布的影响较小。Abstract: The steam gasification of Jinshan petroleum coke catalyzed by potassium salts was investigated in a laboratory fixed-bed reactor, in which the catalytic effects on the gasification activity and the H2 production characteristics were examined. It is observed that the potassium salts can not only effectively lower the gasification temperature and greatly enhance the gasification activity of petroleum coke, but also promote the carbon-water reaction, the water-gas shift reaction and the methane-steam reforming reaction. With the increasing of gasification temperature, the H2 content in gas for non-catalytic gasification increases gradually, while that for the catalytic gasification decreases somewhat, which is probably ascribed to the different behavior of water-gas shift reaction during catalytic gasification. Compared with non-catalytic gasification, the catalytic gasification of petroleum coke can generate a higher hydrogen yield and content (the content of H2 is in the ranges of 47.2%~54.1% for non-catalytic gasification and 55.0%~60.4% for catalytic gasification). The ordering of the catalysis for various potassium salts is K2CO3>KAc>KNO3>K2SO4>KCl, but the type of potassium salts has no effects on the distribution of product gases.
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Key words:
- petroleum coke /
- potassium salt /
- gasification activity /
- H2 production characteristic
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