Effect of Double Transition Metal Salt Catalyst on Fushun Oil Shale Pyrolysis

Shale ash (SA) as the carrier, the ratio of Cu to Ni in the Cu-Ni transition metal salt being, respectively, 1 : 0, 2 : 1, 1 : 1, 1 : 2, 0 : 1, the double transition metal salt catalyst (Cu(m)Ni(n)/SA) was prepared to explore the effect of such catalysts on the pyrolysis behavior and characteristics of Fushun OS. The research results show that the temperature (T(max)) corresponding to the maximum weight loss rate decreased by 12.9°C, 4.0°C, and 3.6°C; and the apparent activation energy decreased by 35.2%, 33.9%, and 29.6%, respectively, after adding catalysts Cu(0)Ni(1)/SA in pyrolysis. The addition of Cu(0)Ni(1)/SA and Cu(2)Ni(1)/SA further improves the shale oil (SO) yield of 3.5% and 3.1%, respectively. Cu(0)Ni(1)/SA produces more aromatic hydrocarbons, which, however, weakens the stability of SO and is of toxicity in use. After analyzing the pyrolysis product—semicoke (SC) and SO—with ATR-FTIR and GC-MS methods, Cu(m)Ni(n)/SA promotes the secondary cracking and aromatization of OS pyrolysis, increasing the content of the compound of olefins and aromatics in SO, and hastening the decomposition of long-chain aliphatic hydrocarbons to short-chain aliphatic hydrocarbons.