CN102911003B

CN102911003B - Method for removing thiophenic sulfur from coking benzene

Info

Publication number: CN102911003B
Application number: CN201210416255.7A
Authority: CN
Inventors: 崔文科; 王小宁; 李波娃; 关亚斌; 王文革
Original assignee: Shanxi Yangmei Fengxi Fertilizer Industry (Group) Co Ltd
Current assignee: Shanxi Yangmei Fengxi Fertilizer Industry (Group) Co Ltd
Priority date: 2012-10-26
Filing date: 2012-10-26
Publication date: 2014-07-23
Anticipated expiration: 2032-10-26
Also published as: CN102911003A

Abstract

The invention discloses a method for removing thiophenic sulfur from coking benzene, belonging to the field of chemical industry production of benzene. The method comprises the following steps: conveying fresh benzene to a benzene heat exchanger by a fresh benzene pump under the pressurizing action, exchanging heat, conveying to a benzene electric heater, mixing hydrogen gas with benzene steam, heating and gasifying, and conveying to a benzene desulfurization reactor; enabling the temperature to be 210-260 DEG C, the pressure to be 0.75-1.05MPa and the air velocity to be 2-3h<-1> in the benzene desulfurization reactor, adding thiophene with hydrogen to be converted into hydrogen sulfide under the action of a catalyst NHDS-8, and adsorbing onto the catalyst; enabling the benzene steam after desulfurization to enter into the benzene heat exchanger so as to convert gaseous benzene into liquid benzene; and carrying out gas-liquid separation on the liquid benzene and the hydrogen in a benzene separator, decompressing the liquid benzene through an adjusting valve, conveying to a benzene process tank, separating the hydrogen through a wire mesh demister, and conveying to a hydrogen circulator for further circulation. The method is better in thiophene removal performance, is capable of reducing the thiophene content in raw materials to be in PPb level, and is low in investment cost and simple to operate.

Description

A kind of method that removes thiophenic sulfur in coking benzene

Technical field

The invention belongs to benzene chemical production field, relate to a kind of method that removes thiophenic sulfur in coking benzene.

Background technology

Coking benzene is the important sources of fine-chemical intermediate, as the benzene of one of important industrial chemicals, just can be refined and be obtained by coking benzene.The coking benzene resource of China is very abundant, at present approximately there is the benzene of 40 %～50 % to come from coking benzene, but carbonization benezene in purified petroleum benzin output less than 20 %, purified petroleum benzin more than 80 % is from the production of petroleum benzene, because domestic market is to the increasing substantially and petroleum resources in short supply of benzene demand, development coking benzene industry has important practical significance and economic benefit greatly.

Slough thiophene in coking benzene and conventionally have physical methods such as the chemical processes such as sulfuric acid washing, shortening, selective oxidation and extracting rectifying, freezing and crystallizing, fractionation by adsorption etc.; but effect is not very desirable; need and the attention of environment protection based on industry, the subject matter of this industry existence is the thiophene-type sulfide in effective elimination coking benzene how at present.

Summary of the invention

The present invention is the problem in order to solve the thiophene-type sulfide in the how effective elimination coking benzene that benzene chemical industry exists, and a kind of method that removes thiophenic sulfur in coking benzene is provided.

The present invention is achieved by the following technical solutions:

A method that removes thiophenic sulfur in coking benzene, comprises the following steps:

(1) fresh benzene being come by fresh benzene tank is delivered to benzene interchanger through fresh benzene pump through pressurization, after interchanger heat exchange, deliver to benzene electric heater, in benzene electric heater, hydrogen mixes with benzene vapor, after the gasification of benzene electric heater heat temperature raising, deliver to benzene desulphurization reactor;

(2), in benzene desulphurization reactor, controlling temperature is that 210-260 DEG C, pressure are 0.75-1.05MPa, air speed 2-3h ^-1time, the hydrogenation of thiophene under catalyst n HDS-8 effect of the thiophene in benzene vapor is converted into hydrogen sulfide, and hydrogen sulfide is adsorbed onto on catalyzer again, completes the desulfurization of benzene;

(3) enter benzene interchanger from desulphurization reactor out through the benzene vapor of desulfurization, in benzene condenser, the benzene of gaseous state obtains condensation and changes into liquid benzene;

(4) condensed liquid phenenyl and hydrogen carry out gas-liquid separation in benzene separator, and liquid phenenyl is delivered to benzene process tank after variable valve decompression, and hydrogen send hydrogen recycle machine further to circulate after wire mesh demister separates.

Shortening method, catalyzer is after reduction, oxidation state metal center is changed into the center, as-reduced metal with high activity, the active metal of NHDS-8 catalyzer is nickel, in the time contacting with catalyzer containing the benzene of organosulfur, on catalyzer, the nickel of reduction-state can make the sulphur on thiophene-type sulfide in raw material react with it, generates NiS, the NiS generating transfers to sulphur on carrier ZnO under hydrogen effect, has kept catalyst activity constant simultaneously.

Its reaction equation is:

Ni＋C ₄H ₄S→NiS＋C ₄H ₄

NiS＋H ₂→Ni＋H ₂S

H ₂S＋ZnO→ZnS＋H ₂O

Because this catalyzer can be transferred to sulphur rapidly on carrier ZnO under hydrogen, in product and tail gas substantially without H ₂s, thereby reach the object of deeply removing thiophene class sulfide.

Adopt U.S. Agilent 7890A gas chromatograph to detect for the trace thiophene in the benzene after desulfurization and total sulfur qualitative analysis, SCD sulphur luminescence detector, PPb level sulphur dedicated analysis post 60m × 0.32, detector pressure 5-10Torr, double plasma controller pressure 300-400 Torr, 800 DEG C of burner temperature, hydrogen flow rate 40-50Sccm, oxidant gas flow velocity 60-65 Sccm(Air).Proving that by analytical results this catalyzer has higher activity and selectivity, is a kind of method that removes the thiophene in coking benzene being suitable for that has.

Compared with prior art, the present invention has the following advantages:

(1) NHDS-8 hydrogenating desulfurization adsorptive catalyst has special catalyst structure and higher catalytic activity, selectivity and stability;

(2) have the performance that removes preferably thiophene, in raw material, thiophene content can be down to PPb level;

(3) use this hydrogenation adsorption desulfurize technology low, simple to operate advantage that there is cost of investment, and can deeply removing thiophene sulphur, have broad application prospects.

Embodiment

Embodiment 1

(2), in benzene desulphurization reactor, controlling temperature is that 210-230 DEG C, pressure are 1-1.05MPa, air speed 2.5h ^-1time, the hydrogenation of thiophene under catalyst n HDS-8 effect of the thiophene in benzene vapor is converted into hydrogen sulfide, and hydrogen sulfide is adsorbed onto on catalyzer again, completes the desulfurization of benzene;

Embodiment 2

(2), in benzene desulphurization reactor, controlling temperature is that 225-245 DEG C, pressure are 0.75-1MPa, air speed 2h ^-1time, the hydrogenation of thiophene under catalyst n HDS-8 effect of the thiophene in benzene vapor is converted into hydrogen sulfide, and hydrogen sulfide is adsorbed onto on catalyzer again, completes the desulfurization of benzene;

Embodiment 3

(2), in benzene desulphurization reactor, controlling temperature is that 240-260 DEG C, pressure are 0.9-1MPa, air speed 3h ^-1time, the hydrogenation of thiophene under catalyst n HDS-8 effect of the thiophene in benzene vapor is converted into hydrogen sulfide, and hydrogen sulfide is adsorbed onto on catalyzer again, completes the desulfurization of benzene;

Claims

1. remove a method for thiophenic sulfur in coking benzene, it is characterized in that comprising the following steps:

(2), in benzene desulphurization reactor, controlling temperature is that 210-260 DEG C, pressure are 0.75-1.05MPa, air speed 2-3h ^-1time, the hydrogenation of thiophene under catalyst n HDS-8 effect of the thiophene in benzene vapor is converted into hydrogen sulfide, and hydrogen sulfide is adsorbed onto on catalyzer again, completes the desulfurization of benzene; Wherein, described catalyst n HDS-8 is that active metal is the catalyzer that nickel, carrier are ZnO;