Energy & Fuels, Vol.31, No.6, 5995-6003, 2017
Adjustment of the Product Distribution over a Bifunctional Ca12Al14O33-Supported MnOx Catalyst from Cracking Gasification of the Petroleum Residue
Cracking gasification of the petroleum residue toward expected gas and light oil products is catalyzed in a fluidized bed reactor using calciuM-ahrininate (C(12)A(7)) and IVIn-modified C(12)A(7) as the bifunctiorial catalysts. The performances of the reaction temperature and Mn-modified C(12)A(7) catalysts on the product distribution for the vacuum residue cracking are studied. The results showed that ethylene, propylene, and butylene are the primary products of the petroleum residue cracking over C(12)A(7), reflected in the C-2-C-4 olefinicity of 63.4% at 650 degrees C with catalyst/oil of 7.0. For Mn-modified C(12)A(7) catalysts, the C-2-C-4 olefinicity of the 0.4 wt % Mn/C(12)A(7) catalyst is increased to 66.9%, while that of 1.0 and 2.0 wt % Mn/C(12)A(2) catalysts is decreased to 40.1 and 25.1%, respectively. Besides, the C-4-C-5 hydrocarbon yield is increased from about 3.0 wt % over C(12)A(7) and 0.4 wt % Mn/C(12)A(7) catalysti to approximately 11.5 wt % over 1.0 and 2.0 wt % Mn/C(12)A(7) catalysts. This indicated a technical feasibility for adjusting the product distribution using Mn-modified C(12)A(7) catalysts. Moreover, the Mn-modified Catalysts showed proper residue cracking activity to allow for both the expected light liquid yield of about 59 wt % and the heavy oil conversion ratio of up to 92.0 wt %. Steam gasification of coke on C(12)A(7) and Mn-modified C(12)A(7) catalysts resulted in the syngas products containing H-2 and CO2 contents of about 58.0 and 24.0 % respectively. Furthermore, the possibility of circulating the modified C(12)A(7) catgyst in the vacuum residue cracking gasification process is also verified.