LEAD PRECONCENTRATION AS RAC-(E,E)-N,N-BIS(2-CHLOROBENZYLIDENE)CYCLOHEXANE-1,2-DIAMINE COMPLEXEI FROM WATER AND TOBACCO SAMPLES BY DISPERSIVE LIQUID-LIQUID MICROEXTRACTION

摘要

A dispersive liquid—liquid micro-extraction (DLLME) procedure for determination of Pb(II) in water and tobacco samples has been developed using rac-(E,E)-N,N'-bis(2-chlorobenzylidene)cyclohexane-l,2-diamine as a chelating agent. Factors influencing the efficiency of DLLME have been optimised, including metal solution pH, type and amount of dispersing solvent, type and amount of extraction solvent, amount of chelating agent and sample volume. The optimized conditions for maximum recovery were as foll