Metal carbide nanomaterial catalysts and production method thereof

Patent metadata

Field	Value
Publication number	US-2020246786-A1
Application number	US-202016744383-A
Country	US
Kind code	A1
Filing date	Jan 16, 2020
Priority date	Feb 4, 2019
Publication date	Aug 6, 2020
Grant date	—

Abstract

A catalyst that includes heterogeneous metal carbide nanomaterials and a novel preparation method to synthesize the metal carbide nanomaterials under relatively mild conditions to form an encapsulated transition metal and/or transition metal carbide nanoclusters in a support and/or binder. The catalyst may include confined platinum carbide nanoclusters. The preparation may include the treatment of encapsulated platinum nanoclusters with ethane at elevated temperatures. The catalysts may be used for catalytic hydrocarbon conversions, which include but are not limited to, ethane aromatization, and for selective hydrogenation, with negligible green oil production.

First claim

1 . A method for synthesizing a catalyst comprising the steps of:
mixing a support and/or binder with an aqueous solution of metal precursor, preferably metal nitrate, to form a mixture; drying the mixture to form a dry product; calcinating the dry product; and reducing the dry product to form a catalyst comprising an encapsulated metal nanocluster within the support and/or binder.

2 . The method according to claim 1 , further comprising the step of activating the catalyst in an atmosphere comprising at least one carbon-containing molecule, and the catalyst comprises multiple encapsulated metal nanoclusters.

3 . The method according to claim 2 , wherein the metal is a transition metal, preferably platinum.

4 . The method according to claim 1 , further comprising the step of cooling the dry product in a hydrogen atmosphere.

5 . The method according to claim 1 , wherein the calcinating comprises an air calcination.

6 . The method according to claim 5 , wherein the calcinating occurs at a temperature between 300-800° C., preferably at 550° C., for a certain period, preferably 0.5 to 24 hours, more preferably four hours.

7 . The method according to claim 1 , wherein the catalyst contains between 300-25000 ppm of platinum, and most preferably 500 ppm platinum.

8 . The method according to claim 1 , wherein the dry product is reduced in hydrogen between 300-800° C., preferably at 630° C., for a certain period, preferably 0.5 to 24 hours, more preferably one hour.

9 . The method according to claim 1 , wherein after the reducing step, the dry product is purged with an inert gas, and the ethane activation occurs at temperatures between 300-750° C., for a certain period, cooled to 100° C. in ethane flow, and further cooled to room temperature in an inert atmosphere.

10 . The method according to claim 1 , wherein an inert binder can be added before or after the calcinating step.

11 . The method according to claim 2 , wherein the encapsulated metal nanoclusters have a size close to 1 nm, and said metal nanoclusters are encapsulated within micropores of the support.

12 . The method according to claim 3 , wherein the catalyst has a platinum dispersion greater than 90%.

13 . The method according to claim 2 , wherein the activated catalyst comprises encapsulated platinum carbide nanoclusters having a size close to 1 nm, and wherein the at least one carbon-containing molecule, is preferably ethane.

14 . A catalyst comprising:
a support; and a plurality of metal carbide nanoclusters encapsulated in a plurality of micropores of the support.

15 . The catalyst according to claim 14 , wherein the support is selected from, but not limited to, inorganic oxides, silicon carbide, silicon nitride, boron nitride, carbon, and combinations thereof, preferably an aluminosilicate zeolite, more preferably ZSM-5.

16 . The catalyst according to claim 14 , wherein the metal is a transition metal, preferably platinum.

17 . The catalyst according to claim 14 , wherein the encapsulated platinum carbide nanoclusters have a size close to 1 nm.

18 . The catalyst according to claim 14 , wherein the catalyst has a platinum dispersion greater than 90%.

Assignees

• China Energy Investment Corp Ltd
• Nat Institute Of Clean-And-Low-Carbon Energy

Inventors

• Shan Junjun
• Wang Hui
• Nguyen Lisa
• Miles Joshua
• Cheng Jihong

Classifications

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J35/393

  Metal or metal oxide crystallite size · CPC title

• B01J35/45

  Nanoparticles · CPC title

• B01J2235/10

  Infrared [IR] · CPC title

• Y02P20/52

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