A kind of oxygen carrier for producing high-quality syngas and its preparation method and application

Abstract

The invention relates to an oxygen carrier that generates high-quality synthesis gas and its preparation method and application. The oxygen carrier is CeO 2 with AFe n Al 12‑n o 19 (A=Ba,La) composite, the general formula of this composite metal oxygen carrier is CeO 2 ‑AFe n Al 12‑n o 19 (A=Ba, La), wherein, 0<n≤12, the total molar ratio x of cerium to ferrocerium ranges from 0.1 to 0.9. The preparation process is as follows: first, use barium nitrate or lanthanum nitrate, iron nitrate, and aluminum nitrate as precursors to prepare a nitrate solution, and add ammonium carbonate as a precipitant for co-precipitation. After suction filtration, washing, drying, and roasting, the carrier AFe is obtained. n Al 12‑n o 19 , and then prepare a cerium nitrate solution, impregnate, dry in the shade, dry, non-equilibrium plasma treatment, and then roast. This oxygen carrier not only has a higher CH 4 Conversion rate, H 2 Selective to CO and able to selectively oxidize methane to H 2 / CO is very close to the theoretical value of 2 high-quality syngas.

Description

【Technical field】 [0001] The invention belongs to the field of methane conversion to produce synthesis gas, and in particular relates to an oxygen carrier for producing high-quality synthesis gas and its preparation method and application. 【Background technique】 [0002] In recent years, it has been proven that the world's unconventional natural gas reserves have reached 9 million cubic meters, which has greatly eased human demand for natural gas. Unconventional natural gas generally includes shale gas, tight sand gas, mud gas (biogas), combustible ice, and coal seams Gas or coal mine gas etc. According to the statistics of the International Energy Agency (IEA) in 2012, the proven technically recoverable reserves of unconventional natural gas in my country are about 50 trillion cubic meters, including 36 trillion cubic meters of shale gas and 3 trillion cubic meters of tight gas. meters, and coalbed methane is 9 trillion cubic meters. As my country's non-traditional natural...

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Problems solved by technology

However, due to the disadvantages of high energy consumption, large and complex equipment, large floor space, and high investment and operating costs, the production cost of synthesis gas accounts for about 60% of the total investment and production costs of the entire natural gas chemical process, and the synthetic gas produced Gas H 2 / CO is too high (H 2 / CO=3), not suitable for direct use in Fischer-Tropsch synthesis

The second important way to produce synthesis gas is CH 4 -CO 2 Reforming, due to reduced investment and energy consumption, especially in mitigating the greenhouse gas CO 2 The pressure of emission reduction is of great significance in protecting the environment, so people pay more and more attention to it. However, due to the high cost of noble metal catalysts, nickel-based catalysts are prone to carbon deposition and deactivation, and the synthesis gas H 2 / CO is too low (H 2 / CO=1) and other problems, it is still far from meeting the requirements of industrialization

The currently developed oxygen carriers have shortcomings such as low oxygen loading rate, low quality of synthesis gas, low cycle reactivity, and inability to withstand high reaction temperature.

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