Pyrolysis of Huadian oil shale under catalysis of shale ash

- Under catalysis of shale ash, aliphatics in oil are partially converted to aromatics.
- Under catalysis of shale ash, long-chain aliphatics are converted to shorter ones.
- The ash effects can be promoted by increased ash content or by augmented temperature.
- The cyclization of aliphatics is more contributive to the formation of aromatics.
- CaO in shale ash plays an important role to the general performance of shale ash.

The influence of shale ash on the pyrolysis of Huadian oil shale was investigated. It was found that under the catalysis of shale ash, aliphatics in shale oil were partially converted to aromatics, and the long- chain aliphatics were converted to shorter ones. This effect could be improved by increased content of shale ash or by augmented temperature. Beyond the Diels-Alder reaction for the formation of aromatics, a novel reaction route of cyclization of aliphatics followed by dehydrogenation to aromatics was proposed. The component of CaO in shale ash plays an important role to the general performance of shale ash.