Catalyst used in the production of ethylene and propylene from methanol and/or dimethyl ether, method for preparing the same and method for using the same

Patent metadata

Field	Value
Publication number	US-9844770-B2
Application number	US-201214366156-A
Country	US
Kind code	B2
Filing date	Apr 23, 2012
Priority date	Dec 19, 2011
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

The application provides a catalyst for producing ethylene and propylene from methanol and/or dimethyl ether, and a preparation and application thereof. In the present application, a molecular sieve catalyst co-modified by rare earth metals and silanization is utilized. First, the material containing methanol and/or dimethyl ether reacts on the catalyst to generate hydrocarbons. The hydrocarbons are separated into a C 1 -C 5 component and a C 6 + component. Then the C 6 + component is recycled to the feeding port and fed into the reactor after mixing with methanol and/or dimethyl ether. The above steps are repeated, to finally generate C 1 -C 5 products, in which the selectivity for ethylene and propylene can reach more than 90 wt % in the C 1 -C 5 component, so that the maximal yield can be achieved in the production of ethylene and propylene from methanol and/or dimethyl ether.

First claim

The invention claimed is:

1. A process for producing ethylene and propylene from methanol and/or dimethyl ether, comprising the steps of;
(a) contacting methanol and/or dimethyl ether with a catalyst to generate a first stream containing hydrocarbons, the catalyst produced by the steps consisting of:
(i) impregnating a HZSM-5 and/or a HZSM-11 zeolite molecular sieve in a lanthanum nitrate solution for 1-12 hours, followed by filtering, drying and calcining to obtain a lanthanum-modified molecular sieve;
(ii) impregnating said obtained lanthanum-modified molecular sieve in one or more silicon sources selected from the group consisting of tetramethyl silicate, tetraethyl silicate, and silicon tetraethyl for 1-12 hours, followed by filtering, drying and calcining to obtain a molecular sieve catalyst co-modified by lanthanum and silanization;

(b) separating said first stream obtained from step (a) into a first C 1 -C 5 component and a first C 6+ component;
(c) mixing said first C 6+ component obtained from step (b) with methanol and/or dimethyl ether to generate a mixture material, and contacting the mixture material with said catalyst to generate a second stream containing hydrocarbons;
(d) separating said second stream obtained from step (c) into a second C 1 -C 5 component and a second C 6+ component, wherein said second C 1 -C 5 component contains ethylene and propylene and is collected as a target product and said second C 6+ component is recycled to step (c); and
(e) repeating step (c) and step (d), wherein the mixture material formed by mixing said second C 6+ component obtained in step (d) with methanol and/or dimethyl ether is used in step (c), so that said second C 1 -C 5 component containing ethylene and propylene is obtained continuously;
wherein said catalyst co-modified by lanthanum and silanization is the only catalyst used in the process, said catalyst is loaded by lanthanum, and a surface acidity of said catalyst is modified by silicon compounds; and
wherein a loading amount of said lanthanum is 0.5-5 wt % of a total weight of said catalyst, and a loading amount of said silicon compounds, which is based on silicon oxide, is 0.1-10 wt % of the total weight of said catalyst.

2. The process according to claim 1 , wherein process is carried out at a temperature of 400-600° C. and a pressure of 0-2.0 MPa, and methanol and/or dimethyl ether are fed at a weight hourly space velocity of 0.2-10 h −1 .

3. The process according to claim 1 , wherein the process is conducted in a fixed bed, a moving bed or a fluidized bed reactor.

4. The process according to claim 1 , wherein the loading amount of said lanthanum is 1-5 wt % of the total weight of said catalyst; and the loading amount of said silicon compounds, which is based on silicon oxide, is 1-10 wt % of the total weight of said catalyst.

5. The process according to claim 1 , wherein said silicon source is tetraethyl silicate.

6. A process for producing ethylene and propylene from methanol and/or dimethyl ether, comprising the steps of;
(a) contacting methanol and/or dimethyl ether with a catalyst to generate a first stream containing hydrocarbons, the catalyst produced by the steps consisting of:
(i) impregnating a HZSM-5 and/or a HZSM-11 zeolite molecular sieve in a lanthanum nitrate solution for 1-12 hours, followed by filtering, drying and calcining to obtain a lanthanum-modified molecular sieve;
(ii) impregnating said obtained lanthanum-modified molecular sieve in one or more silicon sources selected from the group consisting of tetramethyl silicate, tetraethyl silicate, and silicon tetraethyl for 1-12 hours, followed by filtering, drying and calcining to obtain a molecular sieve catalyst co-modified by lanthanum and silanization;

(b) separating said first stream obtained from step (a) into a first C 1 -C 5 component and a first C 6+ component;
(c) mixing said first C 6+ component obtained from step (b) with methanol and/or dimethyl ether to generate a mixture material, and contacting the mixture material with said catalyst to generate a second stream containing hydrocarbons;
(d) separating said second stream obtained from step (c) into a second C 1 -C 5 component and a second C 6+ component, wherein said second C 1 -C 5 component contains ethylene and propylene and is collected as a target product and said second C 6+ component is recycled to step (c); and
(e) repeating step (c) and step (d), wherein the mixture material formed by mixing said second C 6+ component obtained in step (d) with methanol and/or dimethyl ether is used in step (c), so that said second C 1 -C 5 component containing ethylene and propylene is obtained continuously;
wherein said catalyst co-modified by lanthanum and silanization is loaded by lanthanum, and a surface acidity of said catalyst is modified by silicon compounds; and wherein a loading amount of said lanthanum is 0.5-5 wt % of a total weight of said catalyst, and a loading amount of said silicon compounds, which is based on silicon oxide, is 0.1-10 wt % of the total weight of said catalyst.

Assignees

• Xu Lei
• Liu Zhongmin
• Zhu Shukui
• Yu Zhengxi
• Dalian Inst Chem & Physics Cas

Inventors

• Xu Lei
• Liu Zhongmin
• Zhu Shukui
• Yu Zhengxi

Classifications

• Y02P20/52

  using catalysts, e.g. selective catalysts · CPC title

• B01J2229/186

  not in framework positions · CPC title

• B01J2229/32

  Reaction with silicon compounds, e.g. TEOS, siliconfluoride · CPC title

• C07C2523/10

  of rare earths · CPC title

• B01J29/405 Primary

  containing rare earth elements, titanium, zirconium, hafnium, zinc, cadmium, mercury, gallium, indium, thallium, tin or lead · CPC title