Propane dehydrogenation method catalyzed by transition metal oxide-silica molecular sieve catalyst

Abstract

The invention relates to propane dehydrogenation technology, and aims to provide a transition metal oxide-silica molecular sieve catalyst catalyzed propane dehydrogenation method. In the method, the transition metal oxide-silica molecular sieve catalyst is loaded into a fixed-bed reactor, and then a reaction gas containing propane is introduced; the temperature of the catalyst bed is controlled to be 400-700° C., and the feed mass space velocity of propane is in the range of 0.01~100h ‑1 . The present invention maintains relatively high propane conversion rate and propylene selectivity, and the reaction temperature is obviously lower than that of the mature process, which is of great significance for energy saving, emission reduction and production safety risk reduction. The catalyst used has excellent anti-coking performance and a single-pass life much higher than that of industrial catalysts, and the hydrogen / hydrocarbon ratio in the product can be greater than 80% in a long-term stable working state. Part of the catalyst can still work continuously for more than 200h in the pure propane atmosphere without any protective gas at normal pressure, which is of great significance to improve the space-time yield of olefins, reduce the power consumption of the reaction process and the cost of product separation.

Description

technical field [0001] The invention belongs to propane dehydrogenation technology, and particularly relates to a method for catalyzing propane dehydrogenation with a metal oxide-silica molecular sieve catalyst. Background technique [0002] Propylene is one of the two basic organic chemical raw materials with the highest output in the world. Its downstream derivatives, such as polypropylene (accounting for more than 50% of propylene demand), acrylonitrile, acrylic acid, propylene oxide, etc., play an indispensable role in the development of today's society. or missing roles. It can be said that the production of propylene is one of the important links connecting the upstream and downstream industries of the petrochemical industry. [0003] At present, the production of propylene in my country mainly relies on the by-product / co-production of traditional refining processes such as naphtha steam cracking and catalytic cracking. The energy consumption is large and the yield is...

AI Technical Summary

Problems solved by technology

For example, the Pt / Sn catalyst used in the UOP process technology is basically non-toxic to the environment and has a long catalytic life, and its supporting moving bed technology can regenerate the catalyst on-line to ensure continuous reaction, but Pt is expensive and has poor toxicity resistance. (the sulfur content in the raw material should not be greater than 50ppm), the corresponding moving bed technology is complicated, the device investment is expensive and the power consumption is high

Chromium-based catalyst Cr used by Lummus 2 o 3 / Al 2 o 3 Although the catalytic activity is higher than that of Pt / Sn, and it has the advantages of good tolerance to raw material impurities and low price, but it also has the disadvantages of easy carbon deposition and deactivation, short single-pass life, frequent regeneration, and strong biological toxicity.

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