Method for preparing olefin, aromatic hydrocarbon and hydrogen through steam catalytic conversion of methane

Abstract

The invention relates to a method for preparing olefin, aromatic hydrocarbon and hydrogen by steam catalytic cracking of methane by utilizing a quartz catalytic reactor. The process realizes high-efficiency conversion of methane, and generation of gas-phase polycyclic aromatic hydrocarbon and secondary carbon deposit under steam pressing, steam hardly participates in the reaction, only a trace amount of CO is generated, the steam improves the heat transfer efficiency, and the catalyst stability is high. The conversion rate of methane is 20-70%; the olefin selectivity is 85 to 95 percent; the benzene selectivity is 4.5 to 13 percent; the selectivity of CO is 0.5-2%; carbon deposition is zero. The method has the characteristics of long service lifetime of the catalyst, good oxidation reduction and hydrothermal stability of the catalyst at high temperature, high methane conversion rate and product selectivity, zero carbon deposition, no need of amplification of the catalyst, low industrialization difficulty, easiness in separation of the product, good process repeatability, safety and reliability in operation and the like, and has a wide industrial application prospect.

Description

technical field [0001] The invention relates to the application of a quartz catalytic reactor in steam catalytic cracking methane to olefins, aromatics and hydrogen. The process realizes efficient conversion of methane, generation of steam-compressed gas-phase fused-ring aromatics and secondary carbon deposits, and improvement of heat transfer efficiency by steam. , High catalyst stability and zero carbon deposition. Background technique [0002] The development and effective utilization of natural gas (methane) resources represents the development direction of the contemporary energy structure, and is also one of the important ways to guarantee sustainable development and green energy. In recent years, Western developed countries have also made breakthroughs in the development of shale gas and "combustible ice", and a "shale gas revolution" has broken out. There are many types of shale gas resources in my country, and the distribution is relatively concentrated. The recove...

AI Technical Summary

Problems solved by technology

For the selective oxidation of methane to produce methanol or formaldehyde, since the oxidation rate of the target product methanol and formaldehyde is much faster than that of the raw material methane, the selectivity of the reaction is low, and it is difficult to apply on a large scale.

[0008] Two patents (application numbers: 201310174960.5, 201511003407.0 and 201511003407.0) have been applied in the early stage. These two patents mainly apply for a metal-doped silicon-based catalyst, which is then placed in the reactor as a fixed bed, fluidized bed or moving bed. The process of catalytic conversion of methane to olefins; the disadvantages of these two methods are that the pressure drop of the catalyst bed is large, the heat conduction of the catalyst is poor, the temperature difference of the bed is large, and the catalyst preparation conditions are harsh and difficult to scale up.

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