Method for producing an aromatic hydrocarbon with an oxygenate as raw material

Abstract

A method for producing an aromatic hydrocarbon with an oxygenate as raw material, includes: i) reacting an oxygenate in at least one aromatization reactor to obtain an aromatization reaction product; ii) separating the aromatization reaction product to obtain a gas phase hydrocarbons flow X and a liquid phase hydrocarbons flow Y; iii) after removing gas and/or a part of the oxygenate from the gas phase hydrocarbons flow X, a hydrocarbons flow X1 containing a non-aromatic hydrocarbon is obtained; or after removing gas and/or a part of the oxygenate from the gas phase hydrocarbons flow X, a reaction is conducted in another aromatization reactor and a separation is conducted to obtain a flow X2 containing a non-aromatic hydrocarbon and a flow X3 containing an aromatic hydrocarbon. The flows are further treated.

Claims

1. A method for producing an aromatic hydrocarbon with an oxygenate as raw material, comprising i) reacting an oxygenate in at least one aromatization reactor to obtain an aromatization reaction product; ii) separating the aromatization reaction product through a separation unit A, to obtain a gas phase hydrocarbons flow X and a liquid phase hydrocarbons flow Y; iii) separating the gas phase hydrocarbons flow X through a separation unit B, to remove at least one substance and/or a part of the oxygenate and to obtain a hydrocarbons flow X1 containing a non-aromatic hydrocarbon; or separating the gas phase hydrocarbons flow X through a separation unit B to remove at least one substance and/or a part of the oxygenate and to obtain a remaining part, subjecting the remaining part to a second aromatization reaction in a second aromatization reactor, and separating the second aromatization reaction product through the separation unit A, to obtain a flow X2 containing a non-aromatic hydrocarbon and a flow X3 containing an aromatic hydrocarbon; iv) subjecting the liquid phase hydrocarbons flow Y and optionally the flow X3 containing an aromatic hydrocarbon to a non-precise rectification in a separation unit C, to obtain a mixed hydrocarbons flow M of an aromatic hydrocarbon having less than or equal to 7 carbon numbers and a flow N of residual hydrocarbons; v) separating the flow N of the residual hydrocarbons through a separation unit D, to obtain a flow K containing a non-aromatic hydrocarbon, a C.sub.8 aromatic hydrocarbon flow J and a C.sub.9.sup.+ aromatic hydrocarbon flow L; vi) recycling one of the hydrocarbons flow X1 containing a non-aromatic hydrocarbon and the flow X2 containing a non-aromatic hydrocarbon, the mixed hydrocarbons flow M of an aromatic hydrocarbon having less than or equal to 7 carbon numbers and/or a part or all of the flow K containing a non-aromatic hydrocarbon, optionally with an additional C.sub.2.sup.+ hydrocarbons flow, to the above oxygenate; or recycling one of the hydrocarbons flow X1 containing a non-aromatic hydrocarbon and the flow X2 containing a non-aromatic hydrocarbon, the mixed hydrocarbons flow M of an aromatic hydrocarbon having less than or equal to 7 carbon numbers and/or a part or all of the flow K containing a non-aromatic hydrocarbon to the aromatization reactor in iii); vii) optionally, reacting the C.sub.9.sup.+ aromatic hydrocarbons flow L in at least one reactor selected from a transalkylation reactor and a dealkylation reactor to obtain a C.sub.8 aromatic hydrocarbon flow L1.

2. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein the liquid phase hydrocarbons flow Y is separated by one of the following two manners: 1) flow Y enters a separation unit C1 and is separated by a non-precise rectification to obtain a mixed hydrocarbons flow M1 of aromatic hydrocarbons having less than or equal to 6 carbon numbers and a hydrocarbons flow N1 having more than 6 carbon numbers, and the hydrocarbons flow N1 enters a separation unit D1 to obtain a C.sub.8 aromatic hydrocarbon flow and a C.sub.9.sup.+ aromatic hydrocarbon flow; 2) flow Y enters a separation unit C2 and is separated by a non-precise rectification to obtain a mixed hydrocarbons flow M2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers and a hydrocarbons flow N2 having more than 7 carbon numbers, and the hydrocarbons flow N2 enters a separation unit D2 to obtain a C.sub.8 aromatic hydrocarbon flow and a C.sub.9.sup.+ aromatic hydrocarbon flow.

3. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein a part or all of the non-aromatic hydrocarbon flow and the flow of the oxygenate come into contact with a catalyst for reaction in the same aromatization reactor or by entering different aromatization reactors; at least one reactor selected from the group consisting of a transalkylation reactor and a dealkylation reactor in the method is used for converting a C.sub.9.sup.+ aromatic hydrocarbon flow in the product of aromatic hydrocarbons to dimethylbenzene; the reaction conditions for said transalkylation reactor are a temperature of 350 to 550° C., a reaction pressure of 0.1 to 5.0 MPa, a molar ratio of hydrogen/hydrocarbon of 1.5:1 to 200:1, a weight space velocity of raw material of 0.1 to 5 h.sup.−1; the reaction conditions of said dealkylation reactor are a reaction temperature of 300 to 800° C., a molar ratio of hydrogen/hydrocarbon of 0.1 to 200:1 and a weight space velocity of the hydrocarbons of 0.5 to 10 h.sup.−1.

4. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, comprising only one aromatization reactor, said method comprising the following steps: a) under process conditions of a temperature of 400 to 550° C., a pressure of 0.01 to 2.0 MPa and a weight space velocity of raw material(s) of 0.1 to 4 h.sup.−1, contacting a flow of oxygenate(s) with a catalyst for reaction in the aromatization reactor to obtain a first hydrocarbons flow; b) removing CO.sub.2 and a part of oxygenate(s) from said first hydrocarbons flow through a first separation unit to obtain a gas phase non-aromatic hydrocarbons flow, a liquid phase hydrocarbons flow containing an aromatic hydrocarbon and an aqueous phase; c) removing at least one substance and a part of oxygenate(s) from said gas phase non-aromatic hydrocarbons flow through a second separation unit to obtain a C.sub.2.sup.+ hydrocarbons flow; d) further separating the liquid phase hydrocarbons flow containing an aromatic hydrocarbon according to one of the following four manners: d1) subjecting the liquid phase hydrocarbons flow containing an aromatic hydrocarbon to non-precise rectification through a third separation unit to obtain a second hydrocarbon flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers and a third hydrocarbon flow of aromatic hydrocarbons having more than 7 carbon numbers, and separating said third hydrocarbons flow through a fourth separation unit to obtain a fourth hydrocarbons flow, a flow containing C.sub.8 aromatic hydrocarbon and a C.sub.9.sup.+ aromatic hydrocarbon flow, and reacting said C.sub.9.sup.+ aromatic hydrocarbon flow in a dealkylation reactor to obtain a C.sub.8 aromatic hydrocarbon flow; obtaining a fifth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers from the second hydrocarbons flow and a part or all of the C.sub.2.sup.+ hydrocarbons flow, wherein said fifth hydrocarbons flow further optionally comprises a part or all of at least one selected from the fourth hydrocarbons flow and a C.sub.2.sup.+ hydrocarbons flow outside the reaction-separation system; and returning said fifth hydrocarbons flow to the oxygenate(s) flow for further reaction; d2) subjecting the liquid phase hydrocarbons flow containing an aromatic hydrocarbon to a non-precise rectification through a third separation unit to obtain a second hydrocarbon flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers and a third hydrocarbons flow of aromatic hydrocarbons having more than 7 carbon numbers, and obtaining a fourth hydrocarbons flow containing non-aromatic hydrocarbons, a flow containing C.sub.8 aromatic hydrocarbons and a first C.sub.9.sup.+ aromatic hydrocarbon flow from said third hydrocarbons flow through a fourth separation unit; obtaining a sixth hydrocarbon flow containing dimethylbenzene from a second C.sub.9.sup.+ aromatic hydrocarbon flow and a methylbenzene flow outside the reaction-separation system through a transalkylation reactor, wherein the second C.sub.9.sup.+ aromatic hydrocarbon flow is selected from one of a part or all of the first C.sub.9.sup.+ aromatic hydrocarbon flow or a mixture of a part or all of the first C.sub.9.sup.+ aromatic hydrocarbon flow and a C.sub.9.sup.+ aromatic hydrocarbon flow outside the reaction-separation system; obtaining a fifth hydrocarbons flow of aromatic hydrocarbon having less than or equal to 7 carbon numbers from the second hydrocarbons flow and a part or all of the C.sub.2.sup.+ hydrocarbons flow, wherein said fifth hydrocarbons flow further optionally comprises a part or all of at least one selected from the fourth hydrocarbons flow and a C.sub.2.sup.+ hydrocarbons flow outside the reaction-separation system; and returning said fifth hydrocarbons flow to the oxygenate(s) flow for further reaction; d3) subjecting the liquid phase hydrocarbons flow containing an aromatic hydrocarbon to a non-precise rectification through a fifth separation unit to obtain a seventh hydrocarbon flow of aromatic hydrocarbon having less than or equal to 6 carbon numbers and an eighth hydrocarbons flow of aromatic hydrocarbon having more than 6 carbon numbers, obtaining a ninth hydrocarbons flow containing non-aromatic hydrocarbons, a first methylbenzene flow, a flow containing C.sub.8 aromatic hydrocarbons and a C.sub.9.sup.+ aromatic hydrocarbon flow from said eighth flow through a sixth separation unit; obtaining a fifth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers from a part or all of the C.sub.2.sup.+ hydrocarbons flow and the seventh hydrocarbons flow, wherein said fifth hydrocarbons flow further optionally comprises a part or all of at least one selected from the ninth hydrocarbons flow and a C.sub.2.sup.+ hydrocarbons flow outside the reaction-separation system; and returning said fifth hydrocarbons flow to the oxygenate flow for further reaction; d4) subjecting the liquid phase hydrocarbons flow containing an aromatic hydrocarbon to a non-precise rectification through a fifth separation unit to obtain a seventh hydrocarbons flow of aromatic hydrocarbons having less than or equal to 6 carbon numbers and an eighth hydrocarbons flow of aromatic hydrocarbons having more than 6 carbon numbers, obtaining a ninth hydrocarbon flow containing non-aromatic hydrocarbons, a first methylbenzene flow, a flow containing C.sub.8 aromatic hydrocarbons and a first C.sub.9.sup.+ aromatic hydrocarbon flow from said eighth hydrocarbons flow through a sixth separation unit; contacting a methylbenzene flow and a second C.sub.9.sup.+ aromatic hydrocarbon flow with a catalyst in a transalkylation reactor to obtain a flow containing dimethylbenzene, wherein said second methylbenzene flow is selected from one of a part or all of the first methylbenzene flow or a mixed flow of a part or all of the first methylbenzene flow and a methylbenzene flow outside the reaction-separation system, and said second C.sub.9.sup.+ aromatic hydrocarbon flow is selected from one of a part or all of the first C.sub.9.sup.+ aromatic hydrocarbon flow or a mixed flow of a part or all of the first C.sub.9.sup.+ aromatic hydrocarbon flow and a C.sub.9.sup.+ aromatic hydrocarbon flow outside the reaction-separation system; obtaining a fifth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers from a part or all of the C.sub.2.sup.+ hydrocarbon flow and the seventh hydrocarbons flow, wherein said fifth hydrocarbons flow further optionally comprises a part or all of at least one selected from the ninth hydrocarbon flow and a C.sub.2.sup.+ hydrocarbons flow outside the reaction-separation system; and returning said fifth hydrocarbons flow to the oxygenate(s) flow for further reaction.

5. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, comprising two aromatization reactors, said method comprising the following steps: h) under process conditions of a temperature of 400 to 550° C., a reaction pressure of 0.01 to 2.0 MPa and a weight space velocity of raw material(s) of 0.1 to 4 h.sup.−1, contacting a flow of oxygenate(s) with a catalyst for reaction in a first aromatization reactor to obtain a first hydrocarbons flow; i) removing CO.sub.2 and a part of acidic oxygenate to obtain a first gas phase non-aromatic hydrocarbon flow, a first liquid phase hydrocarbons flow containing aromatic hydrocarbons and an aqueous phase from the first hydrocarbons flow through a first separation unit; j) removing gas and a part of oxygenate(s) from a second hydrocarbons flow through a second separation unit to obtain a C.sub.2.sup.+ non-aromatic hydrocarbons flow, wherein the second hydrocarbons flow is a mixed hydrocarbons flow of the first gas phase non-aromatic hydrocarbon flow and a third flow; k) under process conditions of a temperature of 450 to 650° C., a reaction pressure of 0.01 to 2.0 MPa and a weight space velocity of raw material(s) of 0.1 to 4 h.sup.−1, contacting a fourth hydrocarbons flow with a catalyst in a second aromatization reactor to obtain a fifth hydrocarbons flow, wherein said fourth hydrocarbons flow is selected from a mixed hydrocarbons flow of the C.sub.2.sup.+ non-aromatic hydrocarbons flow and a flow I, wherein the flow I is selected from a part or all of at least one of a C.sub.2.sup.+ non-aromatic hydrocarbon flow outside the reaction-separation system and a sixth flow; l) removing CO.sub.2 and a part of acidic oxygenate to obtain a second gas phase non-aromatic hydrocarbon flow, a second liquid phase hydrocarbons flow containing aromatic hydrocarbons and an aqueous phase from the fifth hydrocarbons flow through a seventh separation unit; m) further separating the first liquid phase hydrocarbons flow and the second liquid phase hydrocarbons flow according to one of the following four manners: m1) separating the first liquid phase hydrocarbons flow and the second liquid phase hydrocarbons flow in an eighth separation unit by a non-precise rectification to obtain a seventh hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers and an eighth hydrocarbons flow of aromatic hydrocarbons having more than 7 carbon numbers, and separating said eighth hydrocarbons flow through a ninth separation unit to obtain the ninth flow containing non-aromatic hydrocarbons, a first C.sub.8 aromatic hydrocarbon flow and a first C.sub.9.sup.+ aromatic hydrocarbon flow, reacting said first C.sub.9.sup.+ aromatic hydrocarbon flow or a mixed hydrocarbons flow of the first C.sub.9.sup.+ aromatic hydrocarbon flow and optionally a second C.sub.9.sup.+ aromatic hydrocarbon flow in a dealkylation reactor to obtain a second C.sub.8 aromatic hydrocarbon flow; obtaining a tenth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers from the seventh hydrocarbons flow and a flow H, wherein said flow H is selected from at least one of a C.sub.2.sup.+ hydrocarbons flow outside the reaction-separation system and the ninth flow; and returning said tenth hydrocarbons flow to the oxygenate(s) flow for further reaction; m2) separating the first liquid phase hydrocarbons flow and the second liquid phase hydrocarbons flow in an eighth separation unit by a non-precise rectification to obtain a seventh hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers and an eighth hydrocarbons flow having more than 7 carbon numbers, and separating said eighth hydrocarbons flow through a ninth separation unit to obtain the ninth flow containing non-aromatic hydrocarbons, a C.sub.8 aromatic hydrocarbon flow and a first C.sub.9.sup.+ aromatic hydrocarbon flow, obtaining a tenth flow containing C.sub.8 aromatic hydrocarbons from a second C.sub.9.sup.+ aromatic hydrocarbon flow and a methylbenzene flow outside a reaction-separation system, wherein the second C.sub.9.sup.+ aromatic hydrocarbon flow is selected from the first C.sub.9.sup.+ aromatic hydrocarbon flow or a mixed flow of the first C.sub.9.sup.+ aromatic hydrocarbon flow and a C.sub.9.sup.+ aromatic hydrocarbon flow outside the reaction-separation system, obtaining an eleventh hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers from the seventh hydrocarbons flow and a flow H, wherein said flow H is selected from at least one of a C.sub.2.sup.+ hydrocarbons flow outside the reaction-separation system and the ninth flow; and returning said eleventh hydrocarbons flow to the oxygenate(s) flow for further reaction; m3) separating the first liquid phase hydrocarbons flow and the second liquid phase hydrocarbons flow in a tenth separation unit by a non-precise rectification to obtain a twelfth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers and a thirteenth hydrocarbons flow having more than 7 carbon numbers, and separating said thirteenth hydrocarbons flow through an eleventh separation unit to obtain the fourteenth flow containing non-aromatic hydrocarbons, a C.sub.8 aromatic hydrocarbon flow and a C.sub.9.sup.+ aromatic hydrocarbon flow; obtaining a fifteenth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers from the twelfth hydrocarbons flow and a flow H, wherein said flow H is selected from at least one of C.sub.2.sup.+ hydrocarbons flow outside the reaction-separation system and the fourteenth flow; and returning said fifteenth hydrocarbons flow to the oxygenate flow for further reaction; m4) separating the first liquid phase hydrocarbons flow and the second liquid phase hydrocarbons flow in an eighth separation unit by a non-precise rectification to obtain a twelfth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers and a thirteenth hydrocarbons flow having more than 7 carbon numbers, and separating said thirteenth hydrocarbons flow through a ninth separation unit to obtain a fourteenth flow containing non-aromatic hydrocarbons, a C.sub.8 aromatic hydrocarbon flow and a first C.sub.9.sup.+ aromatic hydrocarbon flow, obtaining a sixteenth flow containing C.sub.8 aromatic hydrocarbons from a second C.sub.9.sup.+ aromatic hydrocarbon flow and a methylbenzene flow outside the reaction-separation system, wherein the second C.sub.9.sup.+ aromatic hydrocarbon flow is selected from the first C.sub.9.sup.+ aromatic hydrocarbon flow or a mixed flow of the first C.sub.9.sup.+ aromatic hydrocarbon flow and a C.sub.9.sup.+ aromatic hydrocarbon flow outside the reaction-separation system, obtaining a seventeenth hydrocarbons flow of aromatic hydrocarbons having less than or equal to 7 carbon numbers from the twelfth hydrocarbons flow and a flow H, wherein said flow H is selected from at least one of C.sub.2.sup.+ hydrocarbon flow outside the reaction-separation system or the fourteenth flow; and returning said seventeenth hydrocarbons flow to the oxygenate flow for further reaction.

6. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein said aromatization reactor comprises at least one of a fluidized-bed reactor, a fixed-bed reactor and a moving-bed reactor, and said transalkylation reactor and dealkylation reactor are fixed-bed reactors.

7. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein said aromatization reactor is a fluidized-bed reactor or a moving-bed reactor, optionally with different regeneration systems or with a common regeneration system.

8. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein said aromatization catalyst comprises at least one molecular sieve active component selected from ZSM-5 and ZSM-11 molecular sieves, wherein the molar ratio of silicon oxide to aluminium oxide in the molecular sieve is from 10:1 to 200:1.

9. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein said alkylation catalyst comprises at least one molecular sieve active component selected from MOR, ZSM-5 and BETA molecular sieves, and said dealkylation process may be free of catalyst or comprises oxide, molecular sieve type dealkylation catalyst.

10. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein the molecular sieve component prior to the molding of the catalyst or the catalyst supporting the modification component is subjected to a high temperature hydro-thermal treatment under conditions of a temperature of 400 to 750° C., a partial pressure of water vapor of 5 to 100%, a treatment time period of 0.5 to 120 hours.

11. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 1, wherein the separation unit A comprises operation units of quenching, alkaline washing or water washing; the separation unit B comprises a pressure swing adsorption, a rectification or an adsorption; or the separation unit D comprises rectification or solvent extraction rectification.

12. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 4, wherein the gas in c) comprises H.sub.2, CO, CO.sub.2, N.sub.2 or CH.sub.4.

13. The method for producing an aromatic hydrocarbon with an oxygenate as raw material according to claim 5, wherein the gas in j) comprises H.sub.2, CO, CO.sub.2, N.sub.2 or CH.sub.4.

Description

THE DESCRIPTION OF FIGURES

(1) FIG. 1 is a flow chart of one embodiment of the present invention;

(2) FIG. 2 is a flow chart of one embodiment of the present invention;

(3) FIG. 3 is a flow chart of one embodiment of the present invention;

(4) FIG. 4 is a flow chart of one embodiment of the present invention;

(5) FIG. 5 is a flow chart of one embodiment of the present invention;

(6) FIG. 6 is a flow chart of one embodiment of the present invention;

(7) FIG. 7 is a flow chart of one embodiment of the present invention;

(8) FIG. 8 is a flow chart of one embodiment of the present invention;

(9) FIG. 9 is a flow chart of the separation manner of the flow Y of the present invention;

(10) FIG. 10 is a flow chart of the separation manner of the flow Y of the present invention.

SPECIFIC EMBODIMENTS

(11) The present invention is further elaborated with the following specific Examples.

Example 1

(12) With reference to the reaction-separation flow chart of, for example, FIG. 1, it had the following steps:

(13) a) contacting the methanol flow 1 in an aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 400° C., a pressure of 0.05 MPa, a methanol weight space velocity of 0.1 h.sup.−1 to obtain the hydrocarbons flow 3;

(14) b) removing CO.sub.2 and a part of oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;

(15) c) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the flow 4 through the separation unit 2 via pressure swing adsorption to obtain a C.sub.2.sup.+ hydrocarbons flow 6;

(16) d) subjecting the hydrocarbons flow 5 to a non-precise rectification through the separation unit 3 to obtain the hydrocarbons flow 7 of aromatic hydrocarbons having less than or equal to 7 carbon numbers and a hydrocarbons flow 8 of aromatic hydrocarbons having more than 7 carbon numbers, and obtaining the hydrocarbons flow 9, the flow 10 containing C.sub.8 aromatic hydrocarbon and the C.sub.9.sup.+ aromatic hydrocarbon flow 11 from the hydrocarbons flow 8 through the separation unit 4;
e) returning the above hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers consisting of the C.sub.2.sup.+ hydrocarbons flow 6, the hydrocarbons flow 7 and the hydrocarbons flow 9 to the above methanol flow 1 for further reaction;
f) reacting the C.sub.9.sup.+ aromatic hydrocarbon flow 11 in a dealkylation reactor under the conditions of 750° C., a hydrocarbons weight space velocity of 8 h.sup.−1 and a reaction pressure of 5 MPa to obtain a C.sub.8 aromatic hydrocarbon flow 201, without any catalyst during this reaction process.

(17) The aromatization reactor was of a fixed-bed form. The catalyst contained ZSM-5 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 10:1, wherein the catalyst was treated for 0.5 hour at 750° C. and a water vapor partial pressure of 100% before use.

(18) In the present Example, the conversion rate of methanol was more than 99%; the yield of dimethylbenzene was 81.5% and the total yield of aromatic hydrocarbon was 84.8%, based on the weight of carbon and hydrogen of methanol.

Example 2

(19) With reference to the reaction-separation flow chart of, for example, FIG. 2, it had the following steps.

(20) a) contacting the methanol flow 1 in an aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 550° C., a pressure of 2.0 MPa, a methanol weight space velocity of 4.0 h.sup.−1 to obtain the hydrocarbons flow 3;

(21) b) removing CO.sub.2 and a part of oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;

(22) c) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the flow 4 through the separation unit 2 via pressure swing adsorption to obtain the C.sub.2.sup.+ hydrocarbons flow 6;

(23) d) subjecting the hydrocarbons flow 5 to a non-precise rectification through the separation unit 3 to obtain the hydrocarbons flow 7 of aromatic hydrocarbons having less than or equal to 7 carbon numbers and the hydrocarbons flow 8 of aromatic hydrocarbons having more than 7 carbon numbers, and obtaining the hydrocarbons flow 9 containing non-aromatic hydrocarbon, the flow 10 containing C.sub.8 aromatic hydrocarbon and the C.sub.9.sup.+ aromatic hydrocarbon flow 11 from the hydrocarbons flow 8 through the separation unit 4;
e) returning the above hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers consisting of the C.sub.2.sup.+ hydrocarbons flow 6, the hydrocarbons flow 7 and the hydrocarbons flow 9 containing non-aromatic hydrocarbons and the C.sub.2.sup.+ hydrocarbons flow 101 outside the reaction-separation system to the above methanol flow 1 for further reaction, wherein the hydrocarbons flow 101 had a weight composition of 43% ethylene, 32% propylene, 20% 1-butene and 5% n-butane, and the C.sub.2.sup.+ hydrocarbons flow 101 and the methanol flow 1 has a weight ratio of 1:10;
f) forming the above C.sub.9.sup.+ aromatic hydrocarbon flow 12 with the above C.sub.9.sup.+ aromatic hydrocarbon flow 11, and contacting the C.sub.9.sup.+ aromatic hydrocarbon flow 12, the methylbenzene flow 13 outside the reaction-separation system through a dealkylation reactor under the conditions of a temperature of 350° C., a hydrogen pressure of 5.0 MPa and a weight space velocity of raw material(s) of 0.1 h.sup.−1 with a catalyst to obtain the hydrocarbons flow 15 containing dimethylbenzene.

(24) The aromatization reactor was of a fluidized-bed form and the transalkylation reactor was of a fixed-bed reactor form. The catalyst contained ZSM-5 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 10:1, wherein the catalyst was treated for 0.5 hour at 750° C. and a water vapor partial pressure of 100% before use.

(25) In the present Example, the conversion rate of methanol was more than 99%; the yield of dimethylbenzene was 90.5% and the total yield of aromatic hydrocarbon was 98.9%, based on the weight of carbon and hydrogen of methanol.

Example 3

(26) With reference to the reaction-separation flow chart of, for example, FIG. 3, it had the following steps:

(27) a) contacting the dimethyl ether flow 1 in an aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 480° C., a pressure of 0.3 MPa, a weight space velocity of raw material of 1.5 h.sup.−1 to obtain the hydrocarbons flow 3;
b) removing CO.sub.2 and a part of oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;
c) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the flow 4 through the separation unit 2 via rectification to obtain the C.sub.2.sup.+ hydrocarbons flow 6;
d) subjecting the hydrocarbons flow 5 to a non-precise rectification through the separation unit 5 to obtain the hydrocarbons flow 21 of aromatic hydrocarbons having less than or equal to 6 carbon numbers and a hydrocarbons flow 22 of aromatic hydrocarbons having more than 6 carbon numbers, and obtaining the hydrocarbons flow 23 containing non-aromatic hydrocarbons, the methylbenzene flow 24, the flow 25 containing C.sub.8 aromatic hydrocarbons and the C.sub.9.sup.+ aromatic hydrocarbon flow 26 from the flow 22 through the separation unit 6;
e) returning the above hydrocarbon flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers consisting of the C.sub.2.sup.+ hydrocarbons flow 6, the hydrocarbons flow 21 and the hydrocarbons flow 23 containing non-aromatic hydrocarbons to the above dimethyl ether flow 1 for further reaction.

(28) The aromatization reactor was of a fluidized-bed reactor form. The catalyst contained ZSM-5 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 30:1, wherein the catalyst was treated for 120 hours at 400° C. and a water vapor partial pressure of 50% before use.

(29) In the present Example, the conversion rate of dimethyl ether was more than 99%; the yield of dimethylbenzene was 82.5% and the total yield of aromatic hydrocarbon is 88.2%, based on the weight of carbon and hydrogen of dimethyl ether.

Example 4

(30) With reference to the reaction-separation flow chart of, for example, FIG. 4, it had the following steps.

(31) a) contacting the dimethyl ether flow 1 in an aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 520° C., a pressure of 0.3 MPa, a weight space velocity of raw material of 0.8 h.sup.−1 to obtain the hydrocarbons flow 3;
b) removing CO.sub.2 and a part of oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;
c) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the flow 4 through the separation unit 2 via rectification to obtain the C.sub.2.sup.+ hydrocarbons flow 6;
d) subjecting the hydrocarbons flow 5 to a non-precise rectification through the separation unit 5 to obtain a hydrocarbons flow 21 of aromatic hydrocarbons having less than or equal to 6 carbon numbers and the hydrocarbons flow 22 of aromatic hydrocarbons having more than 6 carbon numbers, and obtaining the hydrocarbons flow 23 containing non-aromatic hydrocarbons, the methylbenzene flow 24, the flow 25 containing C.sub.8 aromatic hydrocarbons and the C.sub.9.sup.+ aromatic hydrocarbon flow 26 from the flow 22 through the separation unit 6;
e) returning the above hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers consisting of 95% by weight of the flow 6, the hydrocarbons flow 22 and the hydrocarbons flow 23 containing non-aromatic hydrocarbons to the above dimethyl ether flow 1 for further reaction;
f) the methylbenzene flow 24 and the methylbenzene flow 105 outside the reaction-separation system formed the mixed flow 27, wherein the weight ratio of the methylbenzene flow 105 to the methylbenzene flow 24 was 20:80, and the C.sub.9.sup.+ aromatic hydrocarbon flow 26 formed the C.sub.9.sup.+ aromatic hydrocarbon flow 28; contacting the mixed flow 27 and the C.sub.9.sup.+ aromatic hydrocarbon flow 28 in a transalkylation reactor under the reaction conditions of a temperature of 550° C., a hydrogen pressure of 0.5 MPa and a weight space velocity of raw material of 10 h.sup.−1 with a catalyst to obtain the flow 29 containing dimethylbenzene.

(32) The aromatization reactor was of a fluidized-bed reactor form. The catalyst contained ZSM-5 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 100:1, wherein the catalyst was treated for 60 hours at 550° C. and a water vapor partial pressure of 75% before use.

(33) In the present Example, the conversion rate of dimethyl ether was more than 99%; the yield of dimethylbenzene was 88.3% and the total yield of aromatic hydrocarbons was 94.8%, based on the weight of carbon and hydrogen of dimethyl ether.

Example 5

(34) With reference to the reaction-separation flow chart of, for example, FIG. 5, it had the following steps:

(35) h) contacting the methanol flow 1 in the first aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 450° C., a pressure of 0.05 MPa, a weight space velocity of raw material of 1.0 h.sup.−1 to obtain the hydrocarbons flow 3;
i) removing CO.sub.2 and a part of acidic oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;
j) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the hydrocarbons flow 31 through the separation unit 2 via C.sub.5-C.sub.9 gasoline absorption to obtain the C.sub.2.sup.+ non-aromatic hydrocarbons flow 32, wherein the hydrocarbon flow 31 was a mixed hydrocarbon flow of the flow 4 and the gas phase non-aromatic hydrocarbon flow 35;
k) contacting the mixed hydrocarbons flow 33 in the second aromatization reactor under the process conditions of a temperature of 450° C., a pressure of 0.1 MPa, a weight space velocity of raw material of 0.1 h.sup.−1 to obtain the hydrocarbons flow 34, wherein the hydrocarbons flow 33 was a mixed hydrocarbons flow of the flow 32 and the flow I which was selected from a part or all of at least one of the C.sub.2.sup.+ non-aromatic hydrocarbons flow 102 outside the reaction-separation system and the flow 39;
l) removing CO.sub.2 and a part of acidic oxygenates from the hydrocarbons flow 34 through the separation unit 7 to obtain the gas phase non-aromatic hydrocarbons flow 35, the liquid hydrocarbons flow 36 containing aromatic hydrocarbons and the aqueous phase;
m) separating the flow 5 and the flow 36 in the separation unit 8 through a non-precise rectification to obtain the hydrocarbon flow 37 of aromatic hydrocarbons having less than or equal to 7 carbon numbers and the hydrocarbons flow 38 of aromatic hydrocarbons having more than 7 carbon numbers, and separating the flow 38 through the separation unit 9 to obtain the flow 39 containing non-aromatic hydrocarbons, the C.sub.8 aromatic hydrocarbon flow 40 and the C.sub.9.sup.+ aromatic hydrocarbon flow 41;
n) returning the hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers formed by the flow 37 and the flow 39 to the methanol flow 1 for further reaction;
o) contacting the C.sub.9.sup.+ aromatic hydrocarbon flow 41 in a fixed-bed dealkylation reactor under the reaction conditions of a reaction temperature of 350° C., a reaction pressure of 3 MPa, a molar ratio of hydrogen to hydrocarbons of 10:1 and a hydrocarbons weight space velocity of 4 h.sup.−1 with a Pt/ZSM-5 catalyst for reaction to obtain the C.sub.8 aromatic hydrocarbon flow 202;

(36) The first aromatization reactor was of a fluidized-bed reactor form and the second aromatization reactor was of a fixed-bed reactor form; the aromatization catalyst contained ZSM-5 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 100:1, wherein the catalyst was treated for 60 hours at 550° C. and a water vapor partial pressure of 75% before use.

(37) In the present Example, the conversion rate of methanol was more than 99.9%; the yield of dimethylbenzene was 82.0% and the total yield of aromatic hydrocarbon was 89.7%, based on the weight of carbon and hydrogen of methanol.

Example 6

(38) With reference to the reaction-separation flow chart of, for example, FIG. 6, it had the following steps.

(39) h) contacting the methanol flow 1 in the first aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 550° C., a pressure of 2.0 MPa, a weight space velocity of raw material of 4 h.sup.−1 to obtain the hydrocarbons flow 3;
i) removing CO.sub.2 and a part of acidic oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;
j) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the hydrocarbons flow 31 through the separation unit 2 via rectification to obtain the C.sub.2.sup.+ non-aromatic hydrocarbons flow 32, wherein the hydrocarbons flow 31 was a mixed hydrocarbon flow of the flow 4 and 95% by weight of the flow 35;
k) contacting the hydrocarbons flow 33 in the second aromatization reactor under the process conditions of a temperature of 650° C., a pressure of 1.0 MPa, a weight space velocity of raw material of 4 h.sup.−1 with a catalyst to obtain the hydrocarbons flow 34, wherein the hydrocarbons flow 33 was a mixed flow of the flow 32 and the C.sub.2.sup.+ non-aromatic hydrocarbons flow 102 whose weight composition was 35% ethylene, 5% ethane, 29% propylene, 12% propane, 11%1-butene, 7% n-butane, and the weight ratio of the C.sub.2.sup.+ non-aromatic hydrocarbon flow 102 to the flow 32 was 0.5:1;
l) removing CO.sub.2 and a part of acidic oxygenate to obtain the gas phase non-aromatic hydrocarbon flow 35, the liquid phase hydrocarbons flow 36 containing aromatic hydrocarbons and the aqueous phase from the hydrocarbons flow 34 through the separation unit 7;
m) separating the flow 5 and the flow 36 in the separation unit 8 through a non-precise rectification to obtain the hydrocarbons flow 37 of aromatic hydrocarbons having less than or equal to 7 carbon numbers and the hydrocarbons flow 38 having more than 7 carbon numbers, and separating the flow 38 through the separation unit 9 to obtain the flow 39 containing non-aromatic hydrocarbons, the C.sub.8 aromatic hydrocarbon flow 40 and the C.sub.9.sup.+ aromatic hydrocarbon flow 41;
n) returning the hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers formed by the flow 37 and the flow 39 to the methanol flow 1 for further reaction;
o) forming a C.sub.9.sup.+ aromatic hydrocarbon flow 42 by the flow 41, and contacting the C.sub.9.sup.+ aromatic hydrocarbon flow 42 and the methylbenzene 43 outside the reaction-separation system in the dealkylation reactor under a reaction temperature of 400° C., a reaction pressure of 3.0 MPa, a weight space velocity of raw material of 4 h.sup.−1 with a catalyst for reaction to obtain a C.sub.8 aromatic hydrocarbon flow 44;
wherein, both the first aromatization reactor and the second aromatization reactor were of a fluidized-bed reactor form and the same catalyst were used, wherein the catalyst contained ZSM-11 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 75:1 and the catalyst was treated for 16 hours at 700° C. and a water vapor partial pressure of 30% before use.

(40) In the present Example, the conversion rate of methanol was more than 99.9%; the yield of dimethylbenzene was 91.7% and the total yield of aromatic hydrocarbon was 99.2%, based on the weight of carbon and hydrogen of methanol.

Example 7

(41) With reference to the reaction-separation flow chart of, for example, FIG. 7, it had the following steps:

(42) h) contacting an methanol flow 1 in the first aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 500° C., a pressure of 0.5 MPa, a weight space velocity of raw material of 0.8 h.sup.−1 to obtain the hydrocarbons flow 3;
i) removing CO.sub.2 and a part of acidic oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;
j) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the hydrocarbons flow 31 through the separation unit 2 via rectification to obtain the C.sub.2.sup.+ non-aromatic hydrocarbon flow 32, wherein the hydrocarbons flow 31 was a mixed hydrocarbon flow of the flow 4 and the gas phase non-aromatic hydrocarbons flow 35;
k) contacting the hydrocarbons flow 33 in the second aromatization reactor under the process conditions of a temperature of 600° C., a pressure of 0.3 MPa, a weight space velocity of raw material of 1.0 h.sup.−1 with a catalyst to obtain the hydrocarbons flow 34, wherein the hydrocarbons flow 33 was from a flow 32;
l) removing CO.sub.2 and a part of acidic oxygenate(s) to obtain the gas phase non-aromatic hydrocarbon flow 35, the liquid phase hydrocarbon flow 36 containing aromatic hydrocarbons and the aqueous phase from the hydrocarbons flow 34 through the separation unit 7;
m) separating the flow 5 and the flow 36 in the separation unit 10 through a non-precise rectification to obtain the hydrocarbons flow 47 of aromatic hydrocarbons having less than or equal to 7 carbon numbers and the hydrocarbons flow 48 having more than 7 carbon numbers, and separating the flow 48 through the separation unit 11 to obtain the flow 49 containing non-aromatic hydrocarbons, the C.sub.8 aromatic hydrocarbon flow 50 and the C.sub.9.sup.+ aromatic hydrocarbon flow 51;
n) returning the hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers formed by the flow 47 and the flow 49 to the methanol flow 1 for further reaction;
wherein, both the first aromatization reactor and the second aromatization reactor were of a moving-bed reactor form and the same catalysts were used, wherein the catalyst contained ZSM-5 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 150:1 and the catalyst was treated for 24 hours at 600° C. and a water vapor partial pressure of 60% before use.

(43) In the present Example, the conversion rate of methanol was more than 99.9%; the yield of dimethylbenzene was 82.9% and the total yield of aromatic hydrocarbon was 88.5%, based on the weight of carbon and hydrogen of methanol.

Example 8

(44) With reference to the reaction-separation flow chart of, for example, FIG. 8, it had the following steps.

(45) h) contacting the methanol flow 1 and the hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers in the first aromatization reactor with a catalyst for reaction under the process conditions of a temperature of 480° C., a pressure of 0.4 MPa, a weight space velocity of raw material of 0.6 h.sup.−1 to obtain the hydrocarbons flow 3;
i) removing CO.sub.2 and a part of acidic oxygenates from the flow 3 through the separation unit 1 to obtain the gas phase non-aromatic hydrocarbons flow 4, the liquid hydrocarbons flow 5 containing aromatic hydrocarbons and the aqueous phase;
j) removing inorganic gases such as H.sub.2, CO, CO.sub.2, N.sub.2 and the like, CH.sub.4 and a part of oxygenates from the hydrocarbons flow 31 through the separation unit 2 via pressure swing adsorption to obtain the C.sub.2.sup.+ non-aromatic hydrocarbons flow 32, the hydrocarbons flow 31 is a mixed hydrocarbons flow of the flow 4 and the flow 35;
k) contacting the hydrocarbons flow 33 in the second aromatization reactor under the process conditions of a temperature of 610° C., a pressure of 0.3 MPa, a weight space velocity of raw material of 0.8 h.sup.−1 with a catalyst to obtain the hydrocarbons flow 34, wherein the hydrocarbons flow 33 was the flow 32;
l) removing CO.sub.2 and a part of acidic oxygenates to obtain the gas phase non-aromatic hydrocarbon flow 35, the liquid phase hydrocarbons flow 36 containing aromatic hydrocarbons and the aqueous phase from the hydrocarbons flow 34 through the separation unit 7;
m) separating the flow 5 and the flow 36 in the separation unit 9 through a non-precise rectification to obtain the hydrocarbons flow 47 of aromatic hydrocarbon having less than or equal to 7 carbon numbers and the hydrocarbons flow 48 having more than 7 carbon numbers, and separating the flow 48 through the separation unit 10 to obtain the flow 49 containing non-aromatic hydrocarbons, the C.sub.8 aromatic hydrocarbon flow 50 and the C.sub.9.sup.+ aromatic hydrocarbon flow 51;
n) returning the hydrocarbons flow 2 of aromatic hydrocarbons having less than or equal to 7 carbon numbers formed by the flow 47 and the flow 49 to the methanol flow 1 for further reaction;
o) the mixed C.sub.9.sup.+ aromatic hydrocarbon flow 52, which was formed by the flow 51 and the C.sub.9.sup.+ aromatic hydrocarbon flow 106 outside the reaction-separation system, reacted with the methylbenzene flow 53 outside the reaction-separation system through a transalkylation reactor under a reaction temperature of 450° C., a hydrogen pressure of 4.0 MPa, a weight space velocity of raw material of 2 h.sup.−1 to obtain the C.sub.8 aromatic hydrocarbon flow 54, wherein the weight ratio of the methylbenzene flow 53 outside the reaction-separation system to the C.sub.9.sup.+ aromatic hydrocarbon flow 52 was 1:5 and the weight ratio of the flow 106 to the flow 51 was 1:5;
wherein, both the first aromatization reactor and the second aromatization reactor were of a fluidized-bed reactor form, the transalkylation reactor was of a fixed-bed form, and they comprised the same catalysts, wherein the catalyst contained ZSM-5 molecular sieve active components having silicon oxide and aluminium oxide in a molar ratio of 150:1 and the catalyst was treated for 24 hours at 600° C. and a water vapor partial pressure of 60% before use.

(46) In the present Example, the conversion rate of methanol was more than 99.9%; the yield of dimethylbenzene was 87.6% and the total yield of aromatic hydrocarbon was 95.2%, based on the weight of carbon and hydrogen of methanol.

Comparative Example 1

(47) The reaction-separation procedure of producing aromatic hydrocarbons with an oxygenate comprised one aromatization reactor. The byproducts, i.e. non-aromatic hydrocarbons and benzene and methylbenzene, were taken as product directly, and were not subjected to a cycle conversion to aromatic hydrocarbons; the raw materials, the forms of aromatization reactors and the reaction conditions were the same as those of Example 1. The conversion rate of methanol was more than 99.9%, the total yield of aromatic hydrocarbon was 49.6% and the yield of dimethylbenzene was 29.8%.

Comparative Example 2

(48) The reaction-separation procedure of producing aromatic hydrocarbons with an oxygenate comprised one aromatization reactor; only benzene and methylbenzene in the product were returned to the reactor and converted to dimethylbenzene through alkylation. The raw materials, the forms of aromatization reactors, the reaction conditions and the operation conditions were the same as those of Example 3. The conversion rate of methanol was more than 99.9%, the total yield of aromatic hydrocarbon was 53.4% and the yield of dimethylbenzene was 35.2%.