Removal of Cu, Ir, Pd and Os ions in the form of chelates from wastewaters by naphthalene

Abstract

New effective methods have been developed for the removal of trace amounts of Cu(II), Ir(III), Pd(II) and Os(VIII) ions from wastewaters. These heavy metal ions were allowed to form chelates with 1‐phenyl‐4,4,6‐trimethyl(1H,4H)‐pyrimidine‐2‐thiol (PTPT) and then adsorbed on macrocrystalline naphthalene in a fluidized bed reactor. The metal‐PTPT chelates were also extracted into molten naphthalene in a batch reactor. The percentage removals of these metals by both methods were found to be almost 100%. Those methods were evaluated with synthetic and real wastewaters containing several metal ions. The percentage removal decreased only to 96 to 99%, due to interference from other metals. The naphthalene can be recycled in the process after removing metals with a HNO₃or NaOH solution.

Key words:

• Heavy metal
• pollution control
• adsorption
• extraction
• naphthalene

Notes

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