Chelating resin and process for making same
AssigneeOlin Corporation
InventorsDavid W. Cawlfield, William M. Moore, John L. Stubbs, Jr.
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Abstract
A resin chelating agent and process for making it are disclosed. The process comprises reacting the crosslinked product formed from the reaction of an aqueous suspension of a polyethyleneimine with a polycarboxylic acid with a mixture of a caustic agent comprising an alkali metal or alkaline earth metal hydroxide and carbon bisulfide to produce the finished resin. The resin can be produced in both head and powder form and is capable of selectively removing a large number of metallic contaminants from process and waste water streams. It is also essentially insensitive to the presence of alkali metal and alkaline earth metal ions dissolved in said streams.
Claims27
A process for preparing a resin chelating agent comprising:
- (a) reacting an aqueous suspension of a polyethyleneimine with a polycarboxylic acid to produce a crosslinked polyamido precursor resin;
- (b) breaking up the precursor resin by saturation with a first polar solvent;
- (c) grinding the broken precursor resin to a uniform particle size below about 1 millimeter;
- (d) suspending said ground precursor resin in a second polar solvent and reacting said precursor resin in a mixture comprising carbon bisulfide and a hydroxyl containing compound selected from the group consisting of alkali metal hydroxides, alkaline earth metal hydroxides, and ammonium hydroxide, whereby said resin chelating agent is produced;
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- (e) separating said resin from said mixture.
A resin chelating agent prepared by the process which comprises:
- (a) reacting an aqueous suspension of a polyethyleneimine with a polycarboxylic acid to produce a crosslinked polyamido precursor resin;
- (b) breaking up the precursor resin by saturation with a first polar solvent;
- (c) grinding the broken precursor resin to a uniform particle size below about 1 millimeter;
- (d) suspending said precursor in a polar solvent and reacting said precursor resin a mixture comprising sodium hydroxide and carbon bisulfide, said resin having a sulfur content of between about 30 and about 45 percent by weight and an equivalent Cu.sup.+2 capacity of between about 4 and about 6;
- and
- (e) separating said resin from said mixture.
Dependencies are inferred from the claim text.