Recovery of iron oxide from coal fly ash

Patent · Tue May 31 00:00:00 EDT 1983

OSTI ID:864567

Dobbins, Michael S ^[1]; Murtha, Marlyn J ^[1]

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1. Ames, IA

A high quality iron oxide concentrate, suitable as a feed for blast and electric reduction furnaces is recovered from pulverized coal fly ash. The magnetic portion of the fly ash is separated and treated with a hot strong alkali solution which dissolves most of the silica and alumina in the fly ash, leaving a solid residue and forming a precipitate which is an acid soluble salt of aluminosilicate hydrate. The residue and precipitate are then treated with a strong mineral acid to dissolve the precipitate leaving a solid residue containing at least 90 weight percent iron oxide.

• Research Organization: Ames Laboratory (AMES), Ames, IA; Iowa State Univ., Ames, IA (United States)
• DOE Contract Number: W-7405-ENG-82
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4386057
• Application Number: 06/358,958
• OSTI ID: 864567
• Country of Publication: United States
• Language: English

Related Subjects

recovery
iron
oxide
coal
fly
ash
quality
concentrate
suitable
feed
blast
electric
reduction
furnaces
recovered
pulverized
magnetic
portion
separated
treated
hot
strong
alkali
solution
dissolves
silica
alumina
leaving
solid
residue
forming
precipitate
acid
soluble
salt
aluminosilicate
hydrate
mineral
dissolve
containing
90
weight
percent
mineral acid
coal fly
acid soluble
pulverized coal
fly ash
weight percent
iron oxide
solid residue
soluble salt
alkali solution
residue containing
percent iron
strong alkali
magnetic portion
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