A preparing method of a mercaptan etherification catalyst

Abstract

A preparing method of a mercaptan etherification catalyst is disclosed. The method includes: (1) dipping an Al2O3 carrier with a potassium salt solution, drying, and calcinating at 300-600 DEG C to obtain a K2O / Al2O3 carrier; and (2) adding a molybdenum-containing compound, a nickel-containing compound and a composite auxiliary agent into deionized water to prepare a dipping solution; and (3) dipping the carrier obtained in the step (1), drying and calcinating at 200-400 DEG C to obtain a NiO-MoO3-K2O / Al2O3 catalyst. The Al2O3 carrier is modified by the K2O so as to enhance carbon deposit resistance and stability of the catalyst. The composite auxiliary agent, the molybdenum-containing compound and the nickel-containing compound form a complex, thus weakening interaction of NiO, MoO3 and the Al2O3 carrier, promoting dispersion of active components in the Al2O3 carrier, and enhancing activity of the catalyst. The catalyst is high in activity of removing mercaptan in gasoline, and has good hydrogenation effects for dienes.

Description

technical field [0001] The invention relates to a preparation method of a mercaptan etherification catalyst, in particular to a preparation method of a catalyst used for the reaction of mercaptans and diolefins in catalytic cracking gasoline to generate thioether compounds. Background technique [0002] Catalytic cracking (FCC) gasoline is currently the main source of gasoline. The output of FCC gasoline in my country accounts for more than 70% of the total gasoline output, and the total sulfur content and mercaptan content of FCC gasoline are very high. Generally, the total sulfur content is between 200 and 1000 μg / g, and the mercaptan content is 10-100 μg / g, so reducing the total sulfur and mercaptans in FCC gasoline is the key to producing high-standard clean gasoline. [0003] For the removal of mercaptans in catalytic cracked gasoline, there are mainly Merox deodorization process and non-caustic alkali deodorization process, but these two processes can only oxidize merca...

AI Technical Summary

Problems solved by technology

The catalyst is used to remove mercaptans and dienes in full-fraction catalytic cracking gasoline. The removal efficiency of mercaptans is very high, and there is no alkali residue discharge, but the disadvantage is that the removal rate of dienes needs to be further improved.

The reaction conditions are room temperature ~ 140 ℃, pressure 0.5 ~ 1MPa, agent oil ratio is 1:10 ~ 20; the catalyst is made of SiO 2 -Al 2 o 3 or SiO 2 -ZrO 2 As the carrier, phosphoric acid and polyphosphoric acid are the active components, phosphoric acid and polyphosphoric acid account for 10-80% of the catalyst weight, and the rest is the carrier; in SiO 2 -Al 2 o 3 Middle Al 2 o 3 18-50% by weight, SiO 2 50-82% by weight; in SiO 2 -ZrO 2 Medium SiO 2 and ZrO 2 The molar ratio is 1:1; silica hydrogel prepared by sodium silicate and alumina hydrogel prepared by ammonium nitrate precipitation or Zr(SO 4 ) 2 The hydrolyzate is mixed, and the active components of phosphoric acid and polyphosphoric acid are loaded on the carrier. The transfer rate of mercaptan and thiophene in this method is over 90%, but the disadvantage is that the active components of phosphoric acid and polyphosphoric acid are easy to lose

The hydrodemercaptan process provided by the invention is carried out under the condition of dissolving hydrogen, which significantly reduces energy consumption and hydrogen consumption, but the disadvantage is that the cost of precious metals is relatively high, and they are easily poisoned by sulfides

At a reaction temperature of 120 °C, a pressure of 1.0 MPa, and a space velocity of 10 h -1 And under the condition of hydrogen, the conversion rate of mercaptan can reach 94.9%, but the disadvantage is that the carbon deposition of the catalyst is relatively high, and the stability needs to be further improved

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