Effects Of The Different Style On The Iron-based Catalyst For CO Hydrogenation To Light Olefins

With the rapid development of modern society, energy has become a bottleneck restricting the development of human society, particularly fossil fuels such as oil, etc. These fossil fuels are the cornerstone of contemporary human society depend the survival and progress. Coal as China’s most important energy and how " clean and efficient" use of coal is one of the most important issues in our country. Compared to traditional combustion technology, coal preparation chemical by synthesis gas is considered to be an important way of advanced clean coal utilization,almost all of the currently depleting oil resources from the production of chemicals which can be obtained from the synthesis gas conversion. Light Olefins(ethylene, propylene and butylene) are important foundation feedstocks and core product in the modern petrochemical. However, due to the diversity of CO hydrogenation and complexity of the product composition, a large number of oxygen-containing compounds are generated. At the same time, it is impossible to produce a single product or a few components due to restrictions by ASF distribution, namely the product distribution is difficult to control in the light hydrocarbon components, by-products such as CH4, C02 generation is inevitable, the generation of a large number of C5+ also affect light olefins the yield. Further secondary reactions(such hydrogenation, disproportionation, polymerization reaction) may also limit improve of olefin selectivity. The current core problem is synthesis of a high performance catalyst that can be improve olefin selectivity and effective control of product distribution.This article was prepared a number of different types of Fe-based catalysts and studied Mn K additive effect in CO hydrogenation reaction. Fe-Mn, Fe-Mn-K and supported Fe-Mn-K model catalysts reaction performance made detailed analysis. Combined with some catalyst characterization, Mn-K synergistic actionas as well as strong interaction between the supporter and the active component made a detailed in-depth research that can provide theoretical study for better understanding of the mechanism and reaction phenomenon in CO hydrogenation. The results were summarized as follows:(1) Through the Fe-Mn catalyst system phase and reaction performance analysis shows, a-Fe2O3 iron species as the active precursor more beneficial for olefin formation.(2) In the catalyst system presence Fe-Mn strong interaction, this effect can not effectively promote the olefins formation, but the catalyst degree of dispersion and bits hydrogenation activity can be increased, which additives Mn major contribution to the formation of light olefins.(3) Mn oxides are restrained by the addition of additives K,giving rise to more crystal defects of Fe-Mn compound.(4) By evaluating the performance reactions in the different catalytic systems, the interaction between the supporter and the active component as well as the active component and additives are not advantageous to olefin formation reaction.