RapidDistillationless " Free Cyanide " Determinationbya FlowInjectionLigandExchange Method EMIL

In the first part of this research, extensive speciesdependent cyanide recoveries studies were performed using the approved standard methods available for determination of free cyanide. The data obtained show that serious problems are associated with both the CATC (cyanide amenable to chlorination) and WAD (weak and dissociable cyanide) methods. In the second part, a novel flow injection gas-diffusion method for the determination of free cyanide was developed. Complete cyanide recoveries even in the presence of a large excess of the free CNion were found for the following species: [Zn(CN)4]2-, [Cd(CN)4]2-, [Ni(CN)4J2-, [CU(CN)4P-, [Ag(CNh]-, [Hg(CN)4]2-, and Hg(CNh. No recoveries of CNwere obtained from the species that are considered as non free cyanide producing ones, such as [Fe(CN)6]3-I4-,[CO(CN)6P-,and [Au(CNh]-. The method developed is rapid, selective, reproducible, and easy to automate.