CN109395726B

CN109395726B - Catalyst for selective hydrogenation of fused ring compounds

Info

Publication number: CN109395726B
Application number: CN201710709612.1A
Authority: CN
Inventors: 孔德金; 李经球; 陈雪梅
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2017-08-18
Filing date: 2017-08-18
Publication date: 2021-09-03
Anticipated expiration: 2037-08-18
Also published as: CN109395726A

Abstract

The invention relates to a catalyst for selective hydrogenation of condensed ring compounds, which mainly solves the problems of low hydrogenation selectivity of condensed ring compounds and high loss rate of monocyclic aromatic hydrocarbons in the prior art. The invention provides a polycyclic aromatic hydrocarbon selective hydrogenation catalyst, which comprises: the catalyst contains a non-acidic or weakly acidic porous carrier and at least two metal elements or compounds selected from VIII, IB and IIB loaded on the carrier, and the metal elements or compounds are distributed on the surface of the carrier in a nuclear shell layer manner, so that the hydrogenation selectivity of the condensed ring compound is obviously improved.

Description

Catalyst for selective hydrogenation of fused ring compounds

Technical Field

The invention relates to a catalyst for selective hydrogenation of condensed ring compounds and a preparation method thereof.

Background

The polycyclic aromatic hydrocarbon refers to an aromatic hydrocarbon component with a bicyclic structure and a polycyclic structure, and exists in processes such as catalytic cracking, ethylene tar and PX production in large quantity, for example, the annual yield of catalytic cracking light cycle oil is over 1000 ten thousand, and most of the aromatic hydrocarbon component is used as a diesel oil blending component. In recent years, with the increasing demand of PX in China, PX has a situation of short supply and short demand, and realizing the large-scale and raw material diversification of an aromatic hydrocarbon combination device is one of the key factors for solving the problems of the current PX industrial production. Therefore, it is of great significance to fully utilize the polycyclic aromatic hydrocarbons co-produced by the aromatic hydrocarbon combination device and research the polycyclic aromatic hydrocarbons co-produced by the oil refining device to produce the light aromatic hydrocarbons. From the reaction process, the most critical step for realizing the conversion from the polycyclic aromatic hydrocarbon to the monocyclic aromatic hydrocarbon is to realize the selective hydrogenation of the polycyclic aromatic hydrocarbon and partially hydrogenate the polycyclic aromatic hydrocarbon to generate a monocyclic aromatic hydrocarbon component. In a system with coexistence of monocyclic aromatic hydrocarbon and polycyclic aromatic hydrocarbon, the realization of the selective hydrogenation of the aromatic hydrocarbon is an important process for improving the yield of the monocyclic aromatic hydrocarbon. Noble metals such as platinum and palladium and non-noble metals such as molybdenum and nickel are reported to be used for hydrogenation saturation of polycyclic aromatic hydrocarbons.

CN104117386A discloses a polycyclic aromatic hydrocarbon hydrogenation ring-opening catalyst, which is a Beta molecular sieve component containing 5-100% and noble metals selected from Pt, Ir and Pd of 0.1-3% loaded on the Beta molecular sieve component.

CN102688770A discloses an aromatic hydrogenation catalyst, which is composed of mesoporous zeolite and noble metal, and improves the hydrogenation and dearomatization activity and sulfur resistance of the catalyst.

CN103301874B discloses a method for selective ring opening of polycyclic aromatic hydrocarbons by hydrogenation and a catalyst composition, comprising an acidic molecular sieve loaded VIII group metal oxide and a Mo-containing catalyst, wherein the Mo-containing catalyst is a bimetallic sulfide formed by Mo and transition metal, and the yield of a selective ring opening product is remarkably improved by applying a combined catalyst and a water additive.

CN103666553 discloses a process for hydroconversion of polycyclic aromatic hydrocarbons, wherein polycyclic aromatic hydrocarbons are at least partially saturated in a hydrogenation reaction zone to obtain a conversion rate of polycyclic aromatic hydrocarbons of more than 40% and a yield of monocyclic aromatic hydrocarbons of 4-80%; and then the conversion rate of polycyclic aromatic hydrocarbon is more than 85 percent and the relative yield of monocyclic aromatic hydrocarbon is 4-30 percent through the reaction of a hydrocracking reaction zone, thereby reducing the hydrogen consumption of polycyclic aromatic hydrocarbon conversion. None of the above patent documents relates to a technique for partially hydrogenating a polycyclic aromatic hydrocarbon with high selectivity in a system in which monocyclic and polycyclic aromatic hydrocarbons coexist.

Disclosure of Invention

The invention aims to solve the technical problems of low hydrogenation selectivity of polycyclic aromatic hydrocarbons and high loss of monocyclic aromatic hydrocarbons in the prior art, and provides a novel selective hydrogenation catalyst for polycyclic aromatic hydrocarbons, which has the advantages of high selective hydrogenation rate of polycyclic aromatic hydrocarbons and low loss of monocyclic aromatic hydrocarbons when the catalyst is used for treating materials containing monocyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons.

In order to solve the technical problems, the invention adopts the following technical scheme: a polycyclic aromatic hydrocarbon selective hydrogenation catalyst comprises: contains non-acidic or weakly acidic porous carrier and at least two metal elements or compounds selected from VIII, IB and IIB which are loaded on the carrier and are distributed in a nuclear shell layer.

In the technical scheme, the non-acidic or weakly acidic porous carrier is selected from at least one of alumina, amorphous silica-alumina, kaolin and aluminosilicate. The nuclear phase layer metal is at least one of Zn, Cu, Cd, Ag and their compounds. In a more preferable scheme, the core phase layer metal simultaneously comprises a mixture of Zn and Cu, wherein the weight ratio of Zn to Cu is (0.1-10): 1. zn and Cu have synergistic effect on improving the selective hydrogenation activity of the condensed ring compound.

The shell phase layer metal is at least one selected from Pt, Pd, Ir metal and compounds thereof. In a more preferable scheme, the shell phase layer metal simultaneously comprises a Pt and Pd mixture, wherein the weight ratio of Pt to Pd is (0.1-8): 1, Pt and Pd have synergistic effect on improving the selective hydrogenation activity of the condensed ring compound.

The condensed ring compound selective hydrogenation catalyst comprises, by weight, 0.01-15 parts of nuclear phase layer metal by weight of the total catalyst, and 0.05-8 parts of an optimized scheme; the content of the metal in the shell phase layer is 0.01-5 parts of the total weight of the catalyst, and the optimized scheme is 0.02-3 parts.

In order to solve the second technical problem, the invention adopts the following technical scheme: a preparation method of a catalyst for selective hydrogenation of condensed ring compounds comprises the following steps:

a) dissolving salt containing nuclear phase layer metal in water or non-aqueous solution, loading a layer of metal compound on a carrier by the methods of precipitation, adsorption and impregnation, drying, and roasting at the temperature of 400-600 ℃ to prepare the catalyst I with the nuclear phase layer structure.

b) Dissolving salt containing shell phase layer metal in water or non-aqueous solution, loading on the catalyst I with a core phase layer structure by a dipping, precipitation or coating method, drying, and roasting at the temperature of 400-600 ℃ to prepare the fused ring compound selective hydrogenation catalyst.

Wherein, the metal in the step a) is selected from at least one of a zinc-containing compound, a copper-containing compound, a cadmium-containing compound or a silver-containing compound, wherein the metal is selected from at least one of zinc nitrate, zinc chloride, zinc acetate, copper nitrate, copper carbonate, copper chloride, cadmium nitrate or silver nitrate; the non-aqueous solution is selected from one of alcohol compounds, ketone compounds and petroleum ether, and the non-aqueous solution is selected from one of ethanol, acetone, cyclohexane, n-heptane or toluene; b) the metal salt in the step (A) is at least one selected from platinum-containing compounds, palladium-containing compounds and iridium-containing compounds, and the metal salt is at least one selected from chloroplatinic acid, dinitro platinum ammonium, palladium chloride, palladium nitrate, iridium chloride and chloro-iridic acid; the non-aqueous solution is selected from one of alcohol compounds, ketone compounds and petroleum ether, and the non-aqueous solution is selected from one of ethanol, acetone, cyclohexane, n-heptane or toluene. The catalyst reacts under the conditions that the reaction temperature is 100-500 ℃, the reaction pressure is 1.0-5MPa, the hydrogen-hydrocarbon molar ratio is 1-8 and the feeding weight space velocity is 1-20.

According to the invention, based on the interaction between the core shell layer loaded metals, the electronic characteristics of the shell layer metal can be effectively adjusted, so that the adsorption strength of the shell layer metal to the aromatic hydrocarbon is adjusted, and the selective hydrogenation activity to the polycyclic aromatic hydrocarbon is improved. When the catalyst is used for treating a material containing polycyclic aromatic hydrocarbons, the catalyst has the advantages of high selective hydrogenation rate of the polycyclic aromatic hydrocarbons and high yield of monocyclic aromatic hydrocarbons.

The invention is further illustrated but is not limited by the following description of the examples:

Detailed Description

[ example 1 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A1 with 5 percent (wt) of zinc content, and the catalyst A1 is dipped with a certain chloroplatinic acid solution in equal volume to obtain a core-shell metal layer catalyst B1 with 0.3 percent (wt) of platinum content.

5 g of core-shell metal layer catalyst B1 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. Inverse directionThe starting materials were toluene and naphthalene 90:10 (by weight) and the reaction performance is shown in table 1. Wherein R2/R1 represents the ratio of the hydrogenation rate of naphthalene to the hydrogenation rate of toluene, and the hydrogenation selectivity of the catalyst to polycyclic aromatic hydrocarbon is reflected.

[ example 2 ]

20 g of alumina ball carrier is taken, dipped with a certain copper nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A2 with 5 percent (wt) of copper content, and the catalyst A2 is dipped with a certain chloroplatinic acid solution in equal volume to obtain a core-shell metal layer catalyst B2 with 0.3 percent (wt) of platinum content.

5 g of core-shell metal layer catalyst B2 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 3 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A3 with 2 percent (wt) of zinc content, and the catalyst A3 is dipped with a certain chloroplatinic acid solution in equal volume to obtain a core-shell metal layer catalyst B3 with 0.3 percent (wt) of platinum content.

5 g of core-shell metal layer catalyst B3 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 4 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A4 with 5 percent (wt) of zinc content, and the catalyst A4 is dipped with a certain chloropalladate solution in equal volume to obtain a core-shell metal layer catalyst B4 with 0.3 percent (wt) of palladium content.

5 g of core-shell metal layer catalyst B4 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 5 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate solution in the same volume, dried at 120 ℃ for 4 hours, roasted at 550 ℃ for 4 hours to prepare a modified catalyst A5 with 5 percent (wt) of zinc content, and the catalyst A5 is dipped with a certain chloroiridic acid aqueous solution in the same volume to obtain a core-shell metal layer catalyst B5 with 0.3 percent (wt) of iridium content.

5 g of core-shell metal layer catalyst B5 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 6 ]

20 g of alumina ball carrier is taken, dipped with a certain silver nitrate solution in the same volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A6 with 5 percent (wt) of silver content, and the catalyst A6 in the same volume is dipped with a certain chloroplatinic acid ethanol solution to obtain a core-shell metal layer catalyst B6 with 0.3 percent (wt) of platinum content.

5 g of core-shell metal layer catalyst B6 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw material is tolueneNaphthalene 90:10 (by weight) and the reactivity is shown in table 1.

[ example 7 ]

20 g of alumina ball carrier is taken, dipped with a certain cadmium nitrate solution in the same volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A7 with 5 percent (wt) of cadmium content, and the catalyst A7 is dipped with a certain chloroplatinic acid solution in the same volume to obtain a core-shell metal layer catalyst B7 with 0.3 percent (wt) of platinum content.

5 g of core-shell metal layer catalyst B7 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 8 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate and copper nitrate solution in equal volume, dried at 120 ℃ for 4 hours, roasted at 550 ℃ for 4 hours to prepare a modified catalyst A8 with 2 percent (wt) of zinc and 3 percent (wt) of copper, and the catalyst A8 is dipped with a certain chloroplatinic acid solution in equal volume to obtain a core-shell metal layer catalyst B8 with 0.3 percent (wt) of platinum.

5 g of core-shell metal layer catalyst B8 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 9 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate and copper nitrate solution in equal volume, dried at 120 ℃ for 4 hours, roasted at 550 ℃ for 4 hours to prepare a modified catalyst A9 with 2 percent (wt) of zinc and 3 percent (wt) of copper, and the catalyst A9 is dipped with a certain chloroplatinic acid and palladium chloride solution in equal volume to prepare a core-shell metal layer catalyst B9 with 0.1 percent (wt) of platinum and 0.2 percent (wt) of palladium.

5 g of core-shell metal layer catalyst B9 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 10 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate and copper nitrate solution in equal volume, dried at 120 ℃ for 4 hours, roasted at 550 ℃ for 4 hours to prepare a modified catalyst A10 with 2 percent (wt) of zinc and 3 percent (wt) of copper, and the catalyst A10 is dipped with a certain chloroplatinic acid and chloroiridic acid solution in equal volume to prepare a core-shell metal layer catalyst B10 with 0.1 percent (wt) of platinum and 0.2 percent (wt) of iridium.

5 g of core-shell metal layer catalyst B10 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 11 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate and copper nitrate solution in equal volume, dried at 120 ℃ for 4 hours, roasted at 550 ℃ for 4 hours to prepare a modified catalyst A11 with 2 percent (wt) of zinc and 3 percent (wt) of copper, and the catalyst A11 is dipped with a certain chloroplatinic acid and palladium chloride solution in equal volume to prepare a core-shell metal layer catalyst B11 with 0.05 percent (wt) of platinum and 0.25 percent (wt) of palladium.

5 g of core-shell metal layer catalyst B11 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows:the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 12 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate and copper nitrate solution in equal volume, dried at 120 ℃ for 4 hours, roasted at 550 ℃ for 4 hours to prepare a modified catalyst A12 with 2 percent (wt) of zinc and 3 percent (wt) of copper, and the catalyst A12 is dipped with a certain chloroplatinic acid and palladium chloride solution in equal volume to prepare a core-shell metal layer catalyst B12 with 0.2 percent (wt) of platinum and 0.1 percent (wt) of palladium.

5 g of core-shell metal layer catalyst B12 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 13 ]

20 g of alumina ball carrier is taken, dipped with certain zinc nitrate and silver nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A13 with 2 percent (wt) of zinc content and 3 percent (wt) of silver content, and the catalyst A13 is dipped with certain chloroplatinic acid and palladium chloride solution in equal volume to prepare a core-shell metal layer catalyst B13 with 0.05 percent (wt) of platinum content and 0.25 percent (wt) of palladium content.

5 g of core-shell metal layer catalyst B13 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 14 ]

20 g of alumina ball carrier is taken, dipped with a certain zinc nitrate and cadmium nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A14 with 2 percent (wt) of zinc and 3 percent (wt) of cadmium, and the catalyst A14 is dipped with a certain chloroplatinic acid and palladium chloride solution in equal volume to prepare a core-shell metal layer catalyst B14 with 0.05 percent (wt) of platinum and 0.25 percent (wt) of palladium.

5 g of core-shell metal layer catalyst B14 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 15 ]

20 g of alumina ball carrier is taken, dipped with a certain copper nitrate and cadmium nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A15 with the copper content of 2 percent (wt) and the cadmium content of 3 percent (wt), and the catalyst A15 is dipped with a certain chloroplatinic acid and palladium chloride solution in equal volume to prepare a core-shell metal layer catalyst B15 with the platinum content of 0.05 percent (wt) and the palladium content of 0.25 percent (wt).

5 g of core-shell metal layer catalyst B15 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 16 ]

20 g of alumina ball carrier is taken, dipped with a certain copper nitrate and silver nitrate solution in equal volume, dried for 4 hours at 120 ℃, roasted for 4 hours at 550 ℃ to prepare a modified catalyst A16 with the copper content of 2 percent (wt) and the silver content of 3 percent (wt), and the catalyst A16 is dipped with a certain chloroplatinic acid and palladium chloride solution in equal volume to prepare a core-shell metal layer catalyst B16 with the platinum content of 0.05 percent (wt) and the palladium content of 0.25 percent (wt).

5 g of core-shell metal layer catalyst B16 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 17 ]

A modified catalyst A17 with zinc content of 2% (wt) and copper content of 3% (wt) is prepared by isovolumetrically impregnating 20 g of amorphous silica-alumina ball carrier with a certain solution of zinc nitrate and copper nitrate, drying at 120 ℃ for 4 hours, and calcining at 550 ℃ for 4 hours, and a core-shell metal layer catalyst B17 with platinum content of 0.05% (wt) and palladium content of 0.25% (wt) is prepared by isovolumetrically impregnating a certain solution of chloroplatinic acid and palladium chloride with the catalyst A17.

5 g of core-shell metal layer catalyst B17 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

[ example 18 ]

A carrier prepared from 20 g of dealuminized mordenite (Si/Al is 100) and alumina is taken, a certain amount of zinc nitrate and copper nitrate solution is soaked in the carrier in the same volume, the carrier is dried at 120 ℃ for 4 hours and roasted at 550 ℃ for 4 hours to prepare a modified catalyst A18 with the zinc content of 2 percent (wt) and the copper content of 3 percent (wt), and a certain amount of chloroplatinic acid and palladium chloride solution are co-soaked in the catalyst A18 in the same volume to prepare a core-shell metal layer catalyst B18 with the platinum content of 0.05 percent (wt) and the palladium content of 0.25 percent (wt).

5 g of core-shell metal layer catalyst B18 was placed in a reactor, and hydrogen was introduced to reduce at 450 ℃ for 3 hours, and then cooled to 350 ℃, and hydrogen and a material containing toluene and naphthalene were introduced to contact the catalyst for reaction activity investigation. Inverse directionThe conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

Comparative example 1

20 g of alumina ball carrier is taken and dipped into a certain chloroplatinic acid solution with the same volume to obtain the catalyst B19 with the platinum content of 0.3 percent (wt).

5 g of catalyst B19 was placed in a reactor, and reduced by introducing hydrogen at 450 ℃ for 3 hours, then cooled to 350 ℃ and introduced with hydrogen and the material containing toluene and naphthalene was contacted with the catalyst for activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

Comparative example 2

20 g of alumina ball carrier is taken and dipped into a certain chloroplatinic acid and palladium chloride solution in equal volume to obtain the catalyst B20 with the platinum content of 0.05 percent (wt) and the palladium content of 0.25 percent (wt).

5 g of catalyst B20 was placed in a reactor, and reduced by introducing hydrogen at 450 ℃ for 3 hours, then cooled to 350 ℃ and introduced with hydrogen and the material containing toluene and naphthalene was contacted with the catalyst for activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1The reaction temperature is 350 ℃, the reaction pressure is 3.0MPa, and the hydrogen-hydrocarbon molecular ratio is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

Comparative example 3

20 g of alumina ball carrier is taken, dipped with a certain solution of zinc nitrate and copper nitrate in equal volume, dried for 4 hours at 120 ℃, and roasted for 4 hours at 550 ℃, thus obtaining the modified catalyst B21 with 2 percent (wt) of zinc and 3 percent (wt) of copper.

5 g of catalyst B21 was placed in a reactor, and reduced by introducing hydrogen at 450 ℃ for 3 hours, then cooled to 350 ℃ and introduced with hydrogen and the material containing toluene and naphthalene was contacted with the catalyst for activity investigation. The reaction conditions are as follows: the total weight space velocity is 10 hours^-1Reaction temperature 350The reaction pressure is 3.0MPa, and the molecular ratio of hydrogen to hydrocarbon is 3.0. The reaction raw materials were toluene and naphthalene (90: 10 by weight), and the reaction performance was as shown in table 1.

TABLE 1

Claims

1. A process for selective hydrogenation of condensed ring compounds, wherein a condensed ring compound selective hydrogenation catalyst is employed, said catalyst comprising:

A) containing a non-acidic or weakly acidic porous carrier and supported thereon

B) At least two metal elements or compounds selected from VIII, IB and IIB in the nuclear shell distribution;

the nuclear phase layer metal is at least one of Zn, Cu, Cd, Ag and compounds thereof; the shell phase layer metal is at least one selected from Pt, Pd, Ir metal and compounds thereof.

2. The method according to claim 1, wherein the non-acidic or weakly acidic porous support is selected from at least one of alumina, silica, magnesia, amorphous silica-alumina, kaolin, aluminosilicate.

3. The method of claim 1, wherein the core phase layer metal content is 0.01 to 15 parts by weight based on the total weight of the catalyst.

4. The process of claim 1 wherein the shell phase metal content is from 0.01 to 5 parts by weight based on the total weight of the catalyst.

5. The method of any one of claims 1 to 4, wherein the fused ring compound selective hydrogenation catalyst is prepared by a process comprising:

a) dissolving salt containing nuclear phase layer metal in water or non-aqueous solution, loading a layer of metal compound on a carrier by methods of precipitation, physical adhesion and impregnation, drying, and roasting at the temperature of 400-600 ℃ to prepare a catalyst I with a nuclear phase layer structure;

b) dissolving salt containing shell phase layer metal in water or non-aqueous solution, loading on a catalyst I with a core phase layer structure by a dipping, precipitation or coating method, drying, and roasting at the temperature of 400-600 ℃ to prepare the fused ring compound selective hydrogenation catalyst;

wherein, the metal in the step a) is selected from at least one of a zinc-containing compound, a copper-containing compound, a cadmium-containing compound or a silver-containing compound, and the nonaqueous solution is selected from one of an alcohol compound, a ketone compound and petroleum ether; (ii) a b) The metal salt in the step (A) is at least one selected from platinum-containing compounds, palladium-containing compounds and iridium-containing compounds, and the non-aqueous solution is one selected from alcohol compounds, ketone compounds and petroleum ether.

6. The process as claimed in claim 1, wherein the reaction temperature is 100 ℃ and 500 ℃, the reaction pressure is 1.0 to 5MPa, the hydrogen-hydrocarbon molar ratio is 1 to 8, and the space velocity of the feed weight is 1 to 20.