REMOVAL OF CU, IR, PD AND OS IONS IN THE FORM OF CHELATES FROM WASTEWATERS BY NAPHTHALENE

New effective methods have been developed for the removal of trace amo unts of Cu(II), Ir(III), Pd(II) and Os(VIII) ions from wastewaters. Th ese 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 micro crystalline naphthalene in a fluidized bed reactor. The metal-PTPT che lates 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 w astewaters containing several metal ions. The percentage removal decre ased only to 96 to 99%, due to interference from other metals. The nap hthalene can be recycled in the process after removing metals with a H NO3 or NaOH solution.