In Situ Pyrolysis of Oil Shale with the Copper-Amine Complex as an Efficient Catalyst

The Triassic Chang 7 shale in the Ordos Basin is recognized as an important supplementary resource alongside conventional petroleum reserves. Nevertheless, conventional techniques cannot achieve cost-effective production. In this study, a copper-based catalyst, copper-tetraethylenepentamine (Cu-TEPA), was synthesized and its catalytic performance was evaluated via shale pyrolysis in a sealed system under fixed experimental conditions: a thermal reaction temperature of 450 °C, a constant heating duration of 3 h, and a Cu-TEPA-to-raw shale mass ratio of 0.1 wt %. The introduction of Cu-TEPA resulted in a remarkable enhancement of pyrolysis efficiency and the hydrocarbon recovery rate; the shale oil yield increased significantly by 33.33% as compared with the noncatalytic pyrolysis. Simultaneously, Cu-TEPA exhibited excellent catalytic performance in heteroatom removal, achieving removal rates of 32.8% for sulfur atoms and 55.1% for nitrogen atoms, which significantly improved the quality of the product oil. The copper-amine complex catalyst shows great potential for cost-effective in situ shale oil production.