Stabilized chelating agents for removing hydrogen sulfide

Patent · Mon Jan 01 23:00:00 EST 1990

OSTI ID:6963258

Bedell, S A

This patent describes a method for removing hydrogen sulfide from gas streams. It comprises: passing a gas containing hydrogen sulfide through a stabilized aqueous solution initially comprising: metal ions in a concentration of at least about 100 ppm; a chelating agent in an amount of at least equimolar to the metal ions; a buffering compound in a concentration sufficient to provide a pH between 4 and 11; and an inhibitor in a concentration sufficient to retard degradation of the chelating agents, the inhibitor being selected from a group consisting of iodide ions, bromide ions, nitrites, amino acids, alkyl amines, and combinations thereof; continuously oxidizing the sulfide to elemental sulfur while reducing the metal ions, a portion of the inhibitor combining with free hydroxyl radicals formed in the solution; removing the elemental sulfur from the solution; and oxidizing the metal ions with oxygen to regenerate the solution.

• Assignee: Dow Chemical Co., Midland, MI
• Patent Number(s): US 4891205; A
• Application Number: PPN: US 6-831969A
• OSTI ID: 6963258
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010402* -- Coal
Lignite
& Peat-- Purification & Upgrading
AIR POLLUTION CONTROL
CHALCOGENIDES
CHELATING AGENTS
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CONTROL
DESULFURIZATION
ELEMENTS
FLUIDS
FUEL GAS
FUELS
GAS FUELS
GASEOUS WASTES
GASES
HYDROGEN COMPOUNDS
HYDROGEN SULFIDES
METALS
OXIDATION
POLLUTION CONTROL
REDUCTION
REMOVAL
SULFIDES
SULFUR COMPOUNDS
WASTES