RESIN PENGKHELAT AMBERLITE XAD-16-1 , 5 –DIFENIL KARBAZIDA UNTUK PRA -KONSENTRASI DAN ANALISIS SELEKTIF KROMIU M (V I)

Abstract

Cr(VI) compounds are toxic and carcinogenic, consequently, the development of asensitive method, as well as the selective analysis of chromium in environmentalsample is absolutely essential. A chelating resin Amberlite XAD-16-1,5-Diphenylcarbazide has been synthesized and characterized. Preconcentrated and selectiveanalysis of chromium(VI) by forming complex at H2SO4 0,05 M. The Cr(VI) ionwas retained on XAD-16-DPC mini-column and can be eluted quantitatively withHNO3 5 M and determined by Atomic Absorption Spectrometry. The effect ofH2SO4 concentration, contact time, retention capacity, eluent concentration wereinvestigated. The research shows that retention capacity of Amberlite XAD-16-DPC is 2.24 mg Cr / g XAD for batch method and dynamic retention capacity is24.71 μg Cr / g XAD for column method with time saturated of minicolumn is 16.5second. The precision for this method expressed as coefficient variation is 3.68 %at a 95% confidence level. The limit of detection obtained was 69 ppb. The linierrange can be attained between 100 ppb until 900 ppb with a correlation coefficientis 0.985. This method has a good accuracy according to 100 % of recovery. TheFlow Injection Analysis performance can be showed by enrichment factor,concentration efficiency, and consumptive index obtained was 2, 0.5 / minutes, and6.5 mL, respectively. The study of analytical and Flow Injection Analysisperformance showed that this method can be used to selective analysisChromium(VI) on a ppb level.