Nano Ni—CeO2 catalyst for syngas production and its preparation thereof

Patent metadata

Field	Value
Publication number	US-9480974-B2
Application number	US-201514819708-A
Country	US
Kind code	B2
Filing date	Aug 6, 2015
Priority date	Sep 22, 2014
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

The present invention relates to Nano Ni—CeO 2 catalyst and its preparation thereof useful for syngas production. Particularly, the present invention relates to a process for the activation of methane at low temperature for the production of synthesis gas (mixture of CO and H 2 ) using nanosize Ni—Ce oxide catalyst. More particularly, the present invention relates to a process for the partial oxidation of methane to synthesis gas between temperature range of 450° C. to 800° C. at atmospheric pressure over Ni—CeO 2 solid catalyst. The process provides a methane conversion of 20-98% with H 2 to CO molar ratio of 1.6 to 2 without deactivation till 100 h.

First claim

We claim:

1. A process for the preparation of a Nano Ni—CeO 2 catalyst having a formula NiO—CeO 2 that comprises NiO in the range of 2.5-10 wt % and CeO 2 in the range 97.5-90 wt %, wherein 2-5 nm Ni nanoparticles are present on 30-40 nm CeO 2 nanoparticles, said process comprising the steps of;
a) precipitating Ce(NO 3 ) 3 •6H 2 O in ethanol wherein mole ratio of Ce-salt:ethanol is in the range of 8:130 to 9:150 with 2-5% NH3 solution where Ce(NO 3 ) 3 •6H 2 O was used as the precursor of Ce,
b) maintaining the pH of the mixture between 7-10 and stirring the mixture for a period of 1-2 h at room temperature ranging between 30-40° C.,
c) heating the resultant solution at a temperature range of 80-90° C. for a period of 3-5 hrs to obtain a thick mixture substance,
d) evaporating the thick mixture substance to dryness at a temperature range of 90-100° C. for a period of 15-20 hrs to obtain solid;
e) calcining the solid obtained as obtained in step (d) at a temperature range of 450-650° C. for a time period in the range of 4-8 hours to obtain Ce oxide;
f) adding dropwise Ni(NO 3 ) 2 dissolved in water medium wherein mole ratio of Ni(NO 3 ) 2. 6H 2 O:H 2 O is in the range of 4.5×10 −4 :0.55 to 9×10 −4 :0.55 to the ethanolic solution of cetyltrimethylammonium bromide in mole ratio of Ni:CTAB ranging between 1:0.75 to 1:1 and stirring the solution for a period ranging between 15-30 mins at temperature ranging between 25-35° C. to obtain Ni salt solution,
g) adding Ni salt solution as obtained in step (f) with CeO 2 in mole ratio of Ni:CeO 2 ranging between 1:40 to 1:10 as obtained in step (e) in ethanol followed by adding hydrazine in mole ratio of Ni:hydrazine ranging between 1:40 to 1:160 to adjust pH in the range of 8-9 followed by stirring the mixture for the period ranging between 2-3 hrs at temperature ranging between 25-35° C.,
h) drying the mixture of step g) at temperature ranging between 60-90° C. for a period ranging between15-20 hrs. followed by calcining at a temperature ranging between 450-650 ° C. for a time period ranging between 3-10 hrs. to obtain Nano Ni—Ce oxide catalyst.

2. A process for syngas production using a Ni—CeO 2 catalyst having a formula NiO—CeO 2 that comprises NiO in the range of 2.5-10 wt % and CeO 2 in the range 97.5-90 wt % wherein 2-5 nm Ni nanoparticles are present on 30-40 nm CeO 2 nanoparticles, wherein the said process comprises;
passing O 2 :CH 4 :He mixture with a molar ratio of 1:2:2 to 1:2:7 in a reactor at atmospheric pressure in the presence of Nano Ni—Ce oxide catalyst wherein methane to catalyst ratio (v/v) is in the range of 6:1.25×10 −3 to 20:1.15 at a temperature ranging between 450-800° C. for a period ranging between 1-100 hrs at a gas hourly space velocity (GSHV) ranging between 5000-500000 mlg −1 h −1 to obtain syngas.

3. The process for syngas production as claimed in claim 2 , wherein Nano Ni—Ce oxide catalyst used is in the wt ratio of Ni:CeO 2 from 2.5:97.5 to 10:90.

4. The process for syngas production as claimed in claim 2 , wherein the activation of methane in reactor is done at 450° C.

5. The process for syngas production as claimed in claim 2 , wherein the conversion of methane is in the range of 1-98%.

6. The process for syngas production as claimed in claim 2 , wherein the H 2 /CO ratio of syngas obtained is in the range of 1.6-2.0.

7. The process for syngas production as claimed in claim 2 , wherein the catalyst is stable without any deactivation upto 100 hrs.

Assignees

• Council Scient Ind Res

Inventors

• Rajaram Bal
• Rajib Kumar Singha
• Chandrashekar Pendem
• Sivakumar Konathala Laxmi Narayan
• Ankur Bordoloi

Classifications

• B01J37/08

  Heat treatment {(B01J37/0009, B01J37/0018 take precedence)} · CPC title

• B01J23/83 Primary

  with rare earths or actinides · CPC title

• C01B2203/0261

  containing a catalytic partial oxidation step [CPO] · CPC title

• B01J37/0018

  Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat) · CPC title

• Y02P20/52

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