Method for directly converting synthetic gas into low-carbon olefins

Abstract

The invention discloses a method for preparing low-carbon olefins from synthetic gas, and belongs to the field of olefins. In order to solve the problems that due to a backmixing phenomenon, the retention time is inconsistent, reaction products are widely distributed, and side reactions of olefin secondary reaction and water gas reaction and the like are intensified so as to influence the economy of the process in the traditional process for preparing low-carbon olefins from synthetic gas, a rotating packed bed reactor is used as a reactor, a solid Fischer-Tropsch synthesis catalyst is used or a catalyst is prepared into slurry, and the synthetic gas is converted into the low-carbon olefins. By the method, the selectivity of the low-carbon olefins can be greatly improved, and reaction heat can be quickly removed to stabilize the temperature of a reaction bed.

Description

technical field [0001] The present invention relates to a method for preparing low-carbon olefins, more specifically, the present invention relates to a method for preparing low-carbon olefins from synthesis gas. Background technique [0002] Low-carbon olefins, such as ethylene, propylene, and butene, are important chemical raw materials. At present, they mainly come from the steam cracking process of hydrocarbons such as naphtha and low-molecular alkanes such as propane. With the increasing depletion of petroleum resources and rising petroleum prices, the future energy structure will be biased towards coal, natural gas and biomass. Therefore, new ways to synthesize low-carbon olefins from coal, natural gas or biomass have attracted increasing attention. [0003] There are a variety of process routes for the synthesis of low-carbon olefins by using coal, natural gas or biomass, mainly including conversion into synthesis gas and then direct conversion into low-carbon olefins...

AI Technical Summary

Problems solved by technology

[0005] From the research status at home and abroad in this field, there are mainly the following problems at present: 1. The product distribution is relatively wide, which is unfavorable to the synthesis of low-carbon olefins with high selectivity; Hydrogen reactions and disproportionation reactions) will lead to increased production of low-value by-products such as alkanes

The amount of catalyst used in some test devices is only 1-2ml, which is equivalent to a differential reactor, which cannot reflect the secondary reaction of olefins, and does not mean that there is no secondary reaction, so that there is a big difference between the test results and the industrial results; 3. A large amount of CO is generated due to the water gas reaction 2 , thus resulting in the loss of CO, resulting in a decrease in the yield of olefins; 4. The reaction process is a strongly exothermic process, and there are still difficulties in removing the heat of reaction