Study On Catalytic Gasification Characteristics Of Petroleum Coke

The steam and CO2 gasification (non-catalytic and catalytic) reactivity of petroleum coke was investigated using a fixed-bed reaction set-up and a thermogravimetry. From the steam gasification experiments of petroleum coke, the following results were obtained. In the case of non-catalytic gasification, the gasification acitivity of petroleum coke was quite low. In the case of catalytic gasification, the gasification rate of petroleum coke was elevated obviously, the ratio of CO and CO2 was reduced obviously, and the formation of H2 was strengthened obviously. After the loading of K2CO3 was up to 0.5mmol/g(petroleum coke), the gasification activity of petroleum coke hardly changed with the change of the content of catalysts. The catalytic activity ordering of different potassium salts was K2CO3>KAc>KNO3>K2SO4> KCl. The catalytic activity ordering of different metal salts with the same anion was KNO3> NaNO3>Ca(NO3)2>Ni(NO3)2>Fe(NO3)3>Cu(NO3)2. The catalytic activity ordering of different crop straw ashes was cotton straw ash> corn straw ash> wheat straw ash> rice straw ash.From the CO2 gasification experiments of petroleum coke, the following results were obtained. With the increasing loading of K2CO3, the time at which the gasification reaction was finished, was shortened. In the case of catalytic gasification, both the initial reaction temperature and the temperature at the maximum reaction rate were reduced up to about 300℃. Both the apparent activation energy and the preexponential factor, which were calculated by Freeman method, increased with the increasing loading of catalysts. The relationship between apparent activation energy and preexponential factor followed the kinetic compensation effect. There was a difference between the apparent activation energy from Freeman method and that from Ozawa method.