Sulfur-containing aliphatic polymer for the selective absorption of dissolved metal species
OwnerNorman B. Rainerinventor
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Abstract
A sulfur-containing water insoluble hydrogel polymer for selectively removing trace amounts of dissolved metal species is produced from a reaction product of nitrilotriacetic acid (NTA) and polyethylenimine (PEI) which is then treated in a water-swollen state with carbon disulfide. The polymer has a physical configuration that facilitates formation of a porous stationary bed through which water can pass for treatment.
Claims24
1) A sulfur-containing water insoluble hydrogel polymer comprised of a thermally produced cross-linked polyamide reaction product of nitrilotriacetic acid (NTA) and polyethylenimine (PEI), further reacted with carbon disulfide, said polymer having selective absorption affinity for dissolved heavy metals and having a physical form capable of producing a stationary porous bed through which water can be caused to flow.
18) A sulfur-containing water insoluble hydrogel polymer having the ability to selectively absorb dissolved trace heavy metal species, said polymer having been produced by the steps of:
- a) forming a prepolymer solution by dissolving NTA and PEI in water,
- b) heating said prepolymer solution to drive off the water of solution, and continuing said heating to cause a cross-linking reaction to occur between the NTA and PEI to produce a solid water-insoluble polyamide first reaction product,
- c) contacting said first reaction product with water to produce a water-swollen first reaction product, and
- d) contacting said water-swollen first reaction product with carbon disulfide under conditions that permit said carbon disulfide to vaporize and interact with said water-swollen first reaction product.
Dependencies are inferred from the claim text.