Catalyst for generating high-value olefins from liquefied petroleum gas and preparation method and application thereof

Abstract

The invention discloses a catalyst for generating high-value olefins (propylene, butylenes and isobutylene) from liquefied petroleum gas. The catalyst is characterized by comprising the following components: kaolin, garma-Al2O3, one or more chromic oxides, one or more rare earth oxides, one or more alkaline earth metal oxides and silicon oxide or silicate, wherein the kaolin accounts for 0 to 50 percent, the garma-Al2O3 accounts for 20 to 95 percent, the chromic oxide accounts for 1 to 40 percent, the rare earth oxide accounts for 0 to 20 percent, the alkaline earth metal accounts for 0 to 10percent and the silicon oxide or silicate accounts for 1 to 10 percent. A preparation method of the catalyst comprises the following steps of: pulping the kaolin and boehmite by adding water and stirring for 0 to 2 hours; adding active ingredients, such as a chromic salt, a rare earth metal, an alkali salt and the like into the pulp and stirring for 0 to 2 hours; adjusting the pH value of the mixture to between 1 and 3 with concentrated nitric acid; adding a silicate and an alumina sol into the mixture; spraying and drying the mixture; and roasting the mixture at the temperature of between 450 and 650 DEG C for 0 to 5 hours in a nitrogen atmosphere and roasting the mixture at the temperature of between 380 and 800 DEG C for 0 to 20 hours in air atmosphere to obtain the catalyst in a fluidized bed reactor, wherein the reaction conditions comprise that: the temperature is 500 to 700 DEG C, the absolute pressure is 0.01 to 0.2Mpa and the volume space velocity is 300 to 2,000 per hour, and the liquefied petroleum gas can be the liquefied gas for resident fuel from a catalytic cracker in a refinery and also can be one of or a mixture of propane, butane and isobutene.

Description

technical field [0001] The invention relates to a catalyst for dehydrogenating liquefied petroleum gas to produce high-value olefins and a preparation method thereof, as well as the application of the catalyst in producing high-value olefins from liquefied petroleum gas. Background technique [0002] The main component of liquefied petroleum gas is C 3 and C 4 alkanes. At present, China's petrochemical enterprises produce about 25 million tons of liquefied petroleum gas annually, which was mainly burned as household fuel in the past. With the increasing shortage of oil resources and the popularization of natural gas, liquefied petroleum gas should be transferred to areas with greater economic and social benefits. Correspondingly, my country's demand for low-carbon olefin resources is growing day by day. For example, propylene, as an important organic chemical raw material, can be used to produce polypropylene, acrylonitrile, butanol, octanol, propylene oxide, isopropanol...

AI Technical Summary

Problems solved by technology

The invention solves the problem of directly using liquefied gas to produce high-value olefi

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