Coking gasoline hydrofining process

Abstract

The invention discloses a coking gasoline hydrofining process. According to the process, a fixed bed reactor is adopted; the fixed bed reactor is filled with a hydrodesulfurization denitrification catalyst; the catalyst comprises a carrier and an active ingredient; the carrier is KIT-1 of which a synthesized skeleton structure is doped with a heteroatom Cu<2+>; the active ingredient is a mixture of MO2N, W2N, Mo2C and WC; the catalyst also contains a catalytic assistant; the catalytic assistant is a mixture of TiO2, CeO2, V2O5 and NbPO4; the reaction conditions of the fixed bed reactor are that the reaction temperature is 240 to 350 DEG C, the partial hydrogen pressure is 2 to 3.5 MPa, the volume ratio of hydrogen to oil is 450 to 700; the volume space velocity is 1 to 2 h<-1>. Through the process, the total sulphur content of coking gasoline is controlled to be below 5 ppm, and the service life of the catalyst is prolonged to over 8a.

Description

technical field [0001] The invention relates to a coking gasoline hydrogenation desulfurization refining process, in particular to a coking gasoline hydrogenation refining process using a specific catalyst. Background technique [0002] Coker gasoline, also known as coker naphtha, is a fraction with an initial boiling point up to 180 (205°C) produced during delayed coking. Coking gasoline has high sulfur content and olefin content, low motor octane number (about 60), and poor stability (bromine price 40-60gBr / 100g). Stabilized coking gasoline can only be used as a semi-finished product, and generally needs to be processed Hydrofining to remove nitrogen-containing, sulfur-containing compounds and diolefins before it can be used as a blending component of gasoline for vehicles or as a petrochemical raw material (light oil) to produce ethylene, as a raw material for ammonia synthesis, or as a raw material for catalytic reforming . [0003] The sulfur content of coking gasolin...

AI Technical Summary

Problems solved by technology

[0004] In the existing desulfurization process, hydrofining has been widely used due to its mature environment-friendly technology. However, the sulfur content of the raw materials targeted by the existing hydrogenation process is mostly at the level of several hundred ppm, and for as high as 6000ppm-10,000 The sulfur content in ppm, the catalyst used in the existing hydrorefining process is difficult to adapt to such a high sulfur content, generally there will be two problems: first, the activity of the catalyst decreases rapidly, and the device is under the condition of processing other raw materials The service life of the catalyst can reach 6a (6 years) or even longer, but after dealing with coked gasoline, the service life of the catalyst is only 1-2a

[0005] After analysis, it is found that when the catalyst used in the existing hydrofinishing is used for the hydrofinishing of coked gasoline, the loss of the metal components of the catalyst is relatively large, indicating that the active components on the catalyst are reduced, and the pore volume is much smaller, resulting in the reaction between the reactant and the catalyst. The contact area of ​​the catalyst decreases, which is directly reflected in the decrease of the catalyst activity

At the same time, when producing ethylene feedstock, reformate feedstock, and synthetic ammonia feedstock, coking gasoline requires high operating severity and high hydrogenation depth, which leads to aggravated carbon deposition in the catalyst bed and a rapid increase in pressure drop