US 11,897,781 B2
Method for producing hydrogen cyanide
Martin Steurenthaler, Bad Vilbel (DE); Martin Steffan, Alzenau-Wasserlos (DE); Thomas Müller, Altenstadt (DE); and Manfred Bäuml, Brühl (DE)
Assigned to Evonik Operations GmbH, Essen (DE)
Appl. No. 16/337,156
Filed by EVONIK OPERATIONS GMBH, Essen (DE)
PCT Filed Sep. 26, 2017, PCT No. PCT/EP2017/074381
§ 371(c)(1), (2) Date Mar. 27, 2019,
PCT Pub. No. WO2018/060196, PCT Pub. Date Apr. 5, 2018.
Claims priority of application No. 16191019 (EP), filed on Sep. 28, 2016.
Prior Publication US 2019/0225501 A1, Jul. 25, 2019
Int. Cl. C01C 3/02 (2006.01); B01J 12/00 (2006.01); B01J 19/24 (2006.01); B01J 23/42 (2006.01)
CPC C01C 3/0229 (2013.01) [B01J 12/005 (2013.01); B01J 19/2425 (2013.01); B01J 23/42 (2013.01); B01J 2219/00038 (2013.01); B01J 2219/00051 (2013.01); B01J 2219/00182 (2013.01); B01J 2219/0883 (2013.01); B01J 2219/247 (2013.01)] 16 Claims
 
1. A method for producing hydrogen cyanide, comprising passing a feed mixture comprising ammonia and methane through reaction tubes, coated on the inner surface with a catalyst comprising platinum, at a reaction temperature of 1000° C. to 1400° C. to provide a product gas mixture comprising hydrogen cyanide, hydrogen, unreacted ammonia and unreacted methane, the ammonia concentration in said product gas mixture being higher than the methane concentration in said product gas mixture, wherein for a time period of at least 100 h a concentration difference between said ammonia concentration and said methane concentration is maintained in a range of from 1.05% by volume to 3.0% by volume for at least 80% of the time by adjusting the reaction temperature, adjusting the molar ratio of ammonia to carbon in the feed mixture, adjusting a feed rate of said feed mixture, or any combination of said adjustments.