Process for the production of formaldehyde

Patent metadata

Field	Value
Publication number	US-10457634-B2
Application number	US-201816113859-A
Country	US
Kind code	B2
Filing date	Aug 27, 2018
Priority date	Feb 20, 2015
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

A process is described for the production of formaldehyde, comprising (a) subjecting methanol to oxidation with air in a formaldehyde production unit thereby producing a formaldehyde-containing stream; (b) separating said formaldehyde-containing stream into a formaldehyde product stream and a formaldehyde vent gas stream; wherein the vent gas stream, optionally after treatment in a vent gas treatment unit, is passed to one or more stages of: (i) synthesis gas generation, (ii) carbon dioxide removal, (iii) methanol synthesis or (iv) urea synthesis.

First claim

What is claimed is:

1. A process for producing formaldehyde, comprising:
(a) oxidizing methanol with air in a formaldehyde production unit, thereby producing a formaldehyde-containing stream; and
(b) separating said formaldehyde-containing stream in a separation unit into a formaldehyde product stream and a formaldehyde vent gas stream; wherein the formaldehyde vent gas stream, after treatment in a vent gas treatment unit, is passed to one or more stages of: (i) a synthesis gas generation unit, (ii) a carbon dioxide removal unit, (iii) a methanol synthesis unit or (iv) a urea synthesis unit; wherein
the vent gas treatment unit comprises an emission control system comprising a catalytic combustor to convert the vent gas stream into carbon dioxide, nitrogen, and steam.

2. The process of claim 1 , wherein the formaldehyde production unit comprises an oxidation reactor containing a bed of oxidation catalyst, the process further comprising recycling a portion of the formaldehyde vent gas stream to the oxidation reactor.

3. The process of claim 1 , comprising recycling the formaldehyde vent gas to the methanol synthesis unit.

4. The process of claim 1 , comprising passing the formaldehyde vent gas to the carbon dioxide removal unit; wherein the carbon dioxide removal unit is a unit for removing carbon dioxide from a synthesis gas generated in the synthesis gas generation unit.

5. The process of claim 1 , comprising passing the formaldehyde vent gas to the urea synthesis unit.

6. The process of claim 1 , comprising passing the formaldehyde vent gas to the synthesis gas generation unit, wherein the formaldehyde vent gas is used in the synthesis gas generation unit as a component of a fuel gas.

7. The process of claim 1 , comprising passing the formaldehyde vent gas to the synthesis gas generation unit, wherein the formaldehyde vent gas stream is used in the synthesis gas generation unit as a feedstock.

8. The process of claim 1 , wherein the formaldehyde production unit comprises an oxidation reactor containing a bed of oxidation catalyst, wherein the process is operated without recycling any of the formaldehyde vent gas stream to the oxidation reactor.

9. A process for producing formaldehyde, comprising (a) oxidizing methanol with air in a formaldehyde production unit, thereby producing a formaldehyde-containing stream; and (b) separating said formaldehyde-containing stream into a formaldehyde product stream and a formaldehyde vent gas stream; wherein the formaldehyde vent gas stream, optionally after treatment in a vent gas treatment unit, is passed to one or more stages of: (i) a methanol synthesis unit or (ii) a urea synthesis unit.

10. A process for producing formaldehyde, comprising (a) oxidizing methanol with air in a formaldehyde production unit, thereby producing a formaldehyde-containing stream; and (b) separating said formaldehyde-containing stream into a formaldehyde product stream and a formaldehyde vent gas stream; wherein the formaldehyde vent gas stream, without treatment in a vent gas treatment unit, is passed to one or more stages of a carbon dioxide removal unit operating by either reactive absorption, physical absorption, or pressure-wing adsorption.

Assignees

• Johnson Matthey Plc

Inventors

• Erlandsson Ola
• Magnusson Andreas
• Pach John David
• Sheldon Daniel

Classifications

• Y02P20/52

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

• C10J2300/1853

  Steam reforming, i.e. injection of steam only · CPC title

• C10J2300/1838

  Autothermal gasification by injection of oxygen or steam · CPC title

• C10J2300/0976

  as steam · CPC title

• C10J2300/0959

  Oxygen · CPC title