A kind of C3 selective hydrogenation catalyst, preparation method and hydrogenation method

Abstract

The invention discloses a catalyst for selective hydrogenation of C3 and a preparation method thereof, and a hydrogenation method. The catalyst comprises a carrier and active components loaded on thecarrier, wherein the carrier is Mn-and-Ce-modified Al2O3; Pd is used as a main active component; Ga-Ga2O3 is used as a co-active component; the the co-active component Ga2O3 exists in the form of an amorphous gamma crystal phase; the co-active component Ga is obtained through partial reduction of Ga2O3; the reduction degree of Ga in Ga2O3 is 10-70%; the crystal form of the carrier modified Al2O3 contains a theta phase, and the proportion of the theta phase is greater than 30%; the content of Pd is 0.1-1.0 wt% of the total mass of the carrier; and in the co-active component Ga-Ga2O3, the totalcontent of Ga is 0.05-2.0 wt% of the total mass of the carrier. The catalyst of the invention is capable of resisting trace organic sulfur, has high activity and selectivity for the alkynes and diolefins, and can effectively realize selective hydrogenation and removal of the MAPD liquid phase in a C3 fraction.

Description

technical field [0001] The present invention relates to a C3 field, and furthermore, relates to a C3 selective hydrogenation catalyst, a preparation method and a hydrogenation method. Background technique [0002] In ethylene plants at home and abroad, the carbon three fractions obtained after steam cracking, cryogenic and separation of petroleum hydrocarbons mainly contain propylene, propane, methylacetylene (MA) and propadiene (PD). Affected by the cracking raw material and cracking depth, the MAPD content in the C3 fraction is usually about 1-5% (mol), and sometimes even reaches 6-7% (mol). In order to obtain polymer grade propylene, MAPD must be removed to the required index. [0003] MAPD mainly adopts gas-phase catalytic selective hydrogenation, liquid-phase catalytic selective hydrogenation and catalytic distillation to remove MAPD in the third fraction of carbon in industrial devices. The gas-phase selective hydrogenation process is to heat the carbon three fractio...

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Problems solved by technology

The gas-phase selective hydrogenation process is to heat the carbon three fractions to gasify them, and pass through the catalyst bed in a gaseous state for hydrogenation reaction. In comparison, this process does not need to set up a circulation pipeline, the process flow is straightforward, and the amount of precious metals used in the catalyst is low. , but the reaction temperature is high, the catalyst is easy to coke and has poor resistance to impurity pollution

In the late 1990s, there were many researches and developments on the C3 catalytic rectification hydrogenation process, such as patents US6794552, CN102040446A, CN1690028A, etc. The achievements are mainly to combine the liquid phase catalytic hydrogenation method with the propylene rectification technology, so that the catalyst packing has the The dual functions of catalysis and rectification have high reaction efficiency, no special internal parts are required in the reaction section, and the utilization rate of equipment is high. However, the catalyst replacement of catalytic rectification is cumbersome, and the catalyst in the tower cannot be regenerated. Once poisoned, it must be stopped for replacement, which makes this technology It cannot be widely used. At present, only Yanshan Petrochemical has adopted this process in China.

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