Synthesis and properties of poly(hydroxamic acid) from crosslinked poly(methacrylate)

Area of Science:

• Materials Science
• Polymer Chemistry
• Analytical Chemistry

Background:

• Ion-exchange resins are crucial for metal ion separation and purification.
• Poly(hydroxamic acid) functional groups offer strong chelating properties for specific metal ions.

Purpose of the Study:

• To synthesize and characterize a novel poly(hydroxamic acid) chelating ion-exchange resin.
• To evaluate the resin's metal ion binding capacity and selectivity.
• To demonstrate the resin's application in separating complex metal ion mixtures.

Main Methods:

• Suspension polymerization of methacrylate and divinyl benzene to form crosslinked beads.
• Conversion of ester groups to hydroxamic acid using hydroxylamine in alkaline solution.
• Determination of hydroxamic acid capacity and metal ion binding affinities at different pH levels.

Main Results:

• The synthesized resin possesses a hydroxamic acid capacity of 2.71 mmol/g.
• The resin exhibits high affinity for Fe(III) and Pb ions.
• Metal ion capacities for Fe(III), Pb, Cu, Ni, and Co are significantly pH-dependent.
• Successful separation of Fe(III)CuCo/Ni and PbNi ion mixtures was achieved.

Conclusions:

• The developed poly(hydroxamic acid) resin is an effective chelating agent for metal ions.
• The pH-dependent nature of the resin allows for selective metal ion separation.
• This material shows promise for applications in wastewater treatment and metal recovery.