Production of iron (ii) oxalate
AssigneeVspc Pty Ltd
InventorsJohn WORSLEY, Aabhash SHRESTHA
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Abstract
Disclosed herein is a method for producing iron (II) oxalate from an insoluble iron material, the method comprising digesting the insoluble iron material with a digestion liquor comprising one or more acids, and reacting digested iron species with a source of oxalate, the oxalate being in stoichiometric excess relative to the digested iron species, to form a slurry comprising iron (II) oxalate and residual oxalate: separating the iron (II) oxalate from the slurry to provide a solids stream comprising the iron (II) oxalate and a liquids stream comprising residual oxalate; and recycling the liquids stream as the source of oxalate or a component thereof.
Claims23
A method for producing iron (II) oxalate from an insoluble iron material, the method comprising:
- digesting the insoluble iron material with a digestion liquor comprising one or more acids, and reacting digested iron species with a source of oxalate, the oxalate being in stoichiometric excess relative to the digested iron species, to form a slurry comprising iron (II) oxalate and residual oxalate;
- separating the iron (II) oxalate from the slurry to provide a solids stream comprising the iron (II) oxalate and a liquids stream comprising residual oxalate;
- and
- recycling the liquids stream as the source of oxalate or a component thereof.
The method of any one of the preceding claims, wherein the digestion liquor comprises an aqueous solution of oxalic acid, the oxalic acid providing the source of oxalate.
The method of any one of the preceding claims, wherein the digestion liquor further comprises a mineral acid.
The method of any one of the preceding claims, wherein the insoluble iron feed material comprises iron metal and/or synthetically produced iron compounds.
A method for producing iron (II) oxalate from an iron material comprising impurities, the method comprising:
- digesting the insoluble iron material with a digestion liquor comprising one or more acids, and reacting digested iron species with a source of oxalate, the oxalate being in stoichiometric excess relative to the digested iron species, to form a slurry comprising iron (II) oxalate, residual oxalate, and solid impurities;
- oxidizing the iron (II) oxalate in the slurry to form a reaction solution, the reaction solution comprising soluble iron (III) oxalate, residual oxalate, and solid impurities;
- separating the solid impurities from the reaction solution;
- reducing the soluble iron (III) oxalate and forming a slurry comprising iron (II) oxalate and residual oxalate;
- separating the iron (II) oxalate from the slurry to provide a solids stream comprising the iron (II) oxalate and a liquid stream comprising residual oxalate;
- and
- recycling the liquids stream as the source of oxalate or a component thereof.
The method of any one of the preceding claims, wherein the insoluble iron feed material is digested at a temperature of from about 50° C. to about 100° C. and/or the soluble iron compound is reacted with a source of oxalate at a temperature of from about 50° C. to about 100° C.
The method of any one of the preceding claims, wherein the insoluble iron feed material is digested substantially under atmospheric pressure and/or the soluble iron compound is reacted with the source of oxalate substantially under atmospheric pressure.
The method of any one of the preceding claims, wherein the molar ratio of oxalic acid to iron in the insoluble iron feed material is at least 1.5 times the stoichiometric requirement.
A process for producing iron (II) oxalate, the process comprising:
- providing a feed of an insoluble iron material into a reactor;
- providing a feed of a digestion liquor comprising one or more acids into the reactor;
- contacting the insoluble iron material with the digestion liquor in the reactor to digest the insoluble iron feed material;
- reacting digested iron species in the reactor with a source of oxalate, the oxalate being in stoichiometric excess relative to the digested iron species, to form a slurry comprising iron (II) oxalate and residual oxalate;
- subjecting the slurry to a solid-liquid separation process to provide a solids stream comprising iron (II) oxalate and a liquids stream comprising residual oxalate;
- recycling the liquids stream into the reactor as the source of oxalate or a component thereof.
A process for producing iron (II) oxalate from an iron feed material comprising impurities, the process comprising:
- providing a feed of an insoluble iron material comprising impurities into a reactor;
- providing a feed of a digestion liquor comprising one or more acids into the reactor;
- contacting the insoluble iron material with the digestion liquor in the reactor to digest the insoluble iron feed material;
- reacting digested iron species in the reactor with a source of oxalate, the oxalate being in stoichiometric excess relative to the digested iron species, to form a slurry comprising iron (II) oxalate, residual oxalate, and solid impurities;
- oxidizing the iron (II) oxalate in the slurry to form a reaction solution, the reaction solution comprising soluble iron (III) oxalate, residual oxalate, and solid impurities;
- subjecting the reaction solution to a first solid-liquid separation process to separate the solid impurities from the reaction solution;
- reducing the soluble iron (III) oxalate and forming a slurry comprising iron (II) oxalate and residual oxalate;
- subjecting the slurry to a second solid-liquid separation process to provide a solids stream comprising iron (II) oxalate and a liquids stream comprising residual oxalate;
- recycling the liquids stream into the reactor as the source of oxalate or a component thereof.
Dependencies are inferred from the claim text.