Study On Lattice Oxygen Catalysts In Making Synthesis Gas From Natural Gas

The method making synthetic gas mainly include steam reforming method, combined reforming of methane method, auto thermal reforming and non-catalytic partial oxidation method in present industrial mature system. We find a kind of brand-new catalyzed partial oxidation craft.Catalyst provided the crystal lattice oxygen in this method, the crystal lattice oxygen and methane producted synthesis gas through selective oxidation reaction.The catalyst reducted into the low valent state after the lattice oxygen catalysts participated reaction. Methane and oxygen didn't contact in the oxidizing reaction process,it solved the secure problem; Catalysts was oxidated from ortho states to high valent state with gas phase oxygen.The oxidation process supple lattice oxygen catalysts.Thus the circulation was completed. In the reduction process, the catalyst reacted directly with the air.The reaction need not the extra air separation plant. which also solves the problem of air separation.After preliminary information retrieval,we determined perovskite-type mixed oxide (ABO3) as the main material of lattice oxygen catalysts.The material is a cubic crystal system basing on A or B cation for node, B and oxygen ions constituted BO6 eight icosahedron.In this paper, The author screened different catalytic materials and performance study tests using XRD, H2-TPR, CH4-TPSR, pulse response, a continuous flow reaction, XPS and other methods;The author screened investigate of catalyst and the shape conditions; Oxygen species of catalytic materials were studied.The author screened preparation conditions and the method of catalyst's moulding.We believe that the catalytic material LaFeO3 most suitable for methane selective oxidation reactions, the best preparation conditions have the gel formation temperature for 75~85℃, calcination temperature for 900℃, baking time for 10 hours, agent for the amino acid, amino acid and nitrate ion ratio of 4:3, La Source and purity of raw materials on the nature of catalytic material haven't significant impact; in the reaction temperature 900℃, the total gas flow rate conditions 211/min continuous reaction to the results of the flow rate of methane conversion 93%, CO selectivity of 97.6%, catalytic materials for selective oxidation of methane was 22 g / Kg cat.