Non noble metal based diesel oxidation catalyst

Patent metadata

Field	Value
Publication number	US-10646827-B2
Application number	US-201515112986-A
Country	US
Kind code	B2
Filing date	Jan 21, 2015
Priority date	Jan 21, 2014
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

Disclosed is a cheap and efficient non noble metal based catalyst for the oxidation of diesel or hydrocarbons, its synthesis and its application for diesel oxidation at low temperature. The catalyst comprises a mixed oxide of manganese and cerium, or manganese, cerium and zirconium. The catalyst has improved water and sulphur tolerance.

First claim

We claim:

1. A diesel oxidation catalyst comprising a mixed oxide of A and B, wherein A is Mn and B is Ce or a mixture of Ce and Zr, said catalyst comprises oxide of A in the range of 1-23.314% by weight of the catalyst and oxide of B in the range of 76.686-99% by weight of the catalyst, wherein the catalyst is devoid of noble-metal, and the BET surface area of the catalyst is 150-160 m 2 /g with a pore volume of about 0.381 cm 3 /g;
said catalyst is prepared by a process comprising:
a) mixing salt of A and salt of B in water or a mixture of water and an acid to obtain a solution;
b) adjusting pH of the solution obtained in step (a) in the range of 7-12;
c) heat treating the solution of (b) to a temperature in the range of 100-200° C. for 15-120 minutes to obtain a reaction mixture;
d) cooling and filtering the reaction mixture to obtain a residue; and
e) washing and calcinating the residue obtained in step (d) at a temperature in the range of 300-800° C. for 1-5 hours to obtain the diesel oxidation catalyst.

2. The catalyst according to claim 1 , wherein the salt of A and B is selected from the group consisting of nitrate, acetate.

3. The catalyst according to claim 1 , wherein the acid used is nitric acid.

4. A method for using a diesel oxidation in oxidation of propene and carbon monoxide or mixture thereof from diesel engine exhaust, said method comprising the steps of:
i) heating said catalyst at 500° C. for 1 hr in flow of 10% O 2 in He followed by cooling to a temperature range of 25° C. to 50° C.; and
ii) passing a mixture of carbon monoxide, oxygen and helium gas or a mixture of propene, oxygen and helium gas of said catalyst,
wherein gas hourly space velocity of the mixture of gases is in the range of 20,000 h −1 to 100,000 h −1 ;
wherein the catalyst comprises a mixed oxide of A and B, wherein A is Mn and B is Ce or a mixture of Ce and Zr, said catalyst comprises oxide of A in the range of 1-60% by weight of the catalyst and oxide of B in the range of 40-99% by weight of the catalyst, wherein the catalyst is devoid of noble-metal, and the BET surface area of the catalyst is 150-160 m 2 /g with a pore volume of about 0.381 cm 3 /g.

5. The catalyst according to claim 1 , wherein the catalyst oxidizes carbon monoxide (50% conversion) at a temperature in the range of 30 to 250° C.

6. The catalyst according to claim 1 , wherein the catalyst exhibits sulphur tolerance with oxidation of carbon monoxide (50% conversion) at a temperature in the range of 200 to 300° C.

7. The catalyst according to claim 1 , wherein the catalyst exhibits water tolerance with oxidation of carbon monoxide (50% conversion) at a temperature in the range of 220 to 300° C.

Assignees

• Council Scient Ind Res

Inventors

• Umbarkar Shubhangi B
• Dongare Mohan K
• More Pavan M
• Biradar Ankush V

Classifications

• B01D2255/407

  Zr-Ce mixed oxides · CPC title

• B01D2258/012

  Diesel engines and lean burn gasoline engines · CPC title

• B01D2255/9205

  Porosity · CPC title

• B01D2255/65

  Catalysts not containing noble metals · CPC title

• B01D2255/20715

  Zirconium · CPC title