Ammonia purge gas conversion

Patent · Tue Feb 04 04:00:00 EST 1986

OSTI ID:5965643

Van Dijk, C P; Solbakken, A; Mandelik, B G

In a process for producing ammonia in a first synthesis loop wherein fresh ammonia synthesis gas containing hydrogen, nitrogen, and lesser amounts of argon and methane is combined with a first recycle gas to provide a first combined synthesis gas, a portion of the first combined synthesis gas is reacted over ammonia synthesis catalyst containing iron to provide a first converted gas. A first purge stream is removed from the first converted gas to provide the first recycle gas, and ammonia is recovered from the first synthesis loop. The improvement described in this patent consists of (a) adjusting the hydrogen to nitrogen molar ratio of the fresh ammonia synthesis gas to between 2.80 and 2.98 and removing the first purge stream in sufficient amount to maintain a concentration of argon plus methane in the first synthesis loop between 3 and 7 volume percent and the hydrogen to nitrogen molar ratio in the first synthesis loop between 2.50 and 2.90; (b) introducing the first purge stream to a second synthesis loop in which the first purge stream is combined with a second recycle gas to provide a second combined synthesis gas, reacting a portion of the second combined synthesis gas over ammonia synthesis catalyst comprising a platinum group metal supported on graphite-containing carbon to provide a second converted gas; (c) recovering ammonia from the second synthesis loop; and (d) removing a second purge stream from the second synthesis loop in sufficient amount to maintain the hydrogen to nitrogen molar ratio in the second synthesis loop between 2.00 and 2.50.

• Assignee: The M.W. Kellogg Co., Houston, TX
• Patent Number(s): US 4568531
• OSTI ID: 5965643
• Country of Publication: United States
• Language: English

Related Subjects

090320* -- Inorganic Hydrogen Compound Fuels-- Preparation-- (1976-1989)
10 SYNTHETIC FUELS
ALKANES
AMMONIA
ARGON
CARBON
CATALYSTS
CATALYTIC EFFECTS
CHEMICAL PREPARATION
ELEMENTAL MINERALS
ELEMENTS
FLUIDS
GASES
GRAPHITE
HYDRIDES
HYDROCARBONS
HYDROGEN
HYDROGEN COMPOUNDS
METALS
METHANE
MINERALS
NITROGEN
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NONMETALS
ORGANIC COMPOUNDS
PLATINUM
PLATINUM METALS
QUANTITY RATIO
RARE GASES
RECYCLING
SYNTHESIS
SYNTHESIS GAS
TRANSITION ELEMENTS