Investigation on the catalytic effect of AAEMs on the pyrolysis characteristics of Changji oil shale and its kinetics.

• The AAEMs were selected as catalysts of oil shale to study the pyrolysis process. • The yield of shale oil and gas improved with the presence of AAEMs during pyrolysis. • The AAEMs promote the release of H 2 and reduce the precipitation of C 2 H 4 and C 2 H 6. • Na+ increases the relative content of alkanes in the shale oil and declines alkenes. • The catalysts of Na and Mg reduce the E values of oil shale during pyrolysis. Changji oil shale in Xinjiang Province of China is abundant and characterized by high ash content and low oil content. While, catalytic pyrolysis is an effective method to improve pyrolysis performance. In this paper, CH 3 COONa, (CH 3 COO) 2 Ca and MgO were selected as catalysts of oil shale to investigate the its pyrolysis behavior and pyrolysates characteristics. The results reveal that the three catalysts improve the yields of shale oil and gas. They also promote the release of H 2 and reduce the precipitation of C 2 H 4 and C 2 H 6 in the pyrolysis gas. And CH 3 COONa and MgO improve the formation of CH 4 , while, CH 3 COONa and (CH 3 COO) 2 Ca enhance the yield of CO. In addition, these catalysts have little influence on the component of the spent shale because of its high ash contents. The existence of CH 3 COONa increases the relative content of alkanes in the shale oil and declines the relative content of alkenes, while (CH 3 COO) 2 Ca and MgO play the opposite role. The presence of AAEMs cations increases H/C ratio and the relative content of short-chain aliphatic hydrocarbons in shale oil, making the shale oil lightened. The catalysts of CH 3 COONa and MgO reduce the activation energy of oil shale during pyrolysis. Because Na+ and Mg2+ as polar centers, change the electron cloud distribution of C C bond. The E values of CJ, CJ + Na and CJ + Ca during pyrolysis fluctuated with the entire conversion rates and CJ + Mg exhibited a constantly increasing trend. [ABSTRACT FROM AUTHOR]