RESUMEN
Objective To develop a new method for the determination of trace manganese in water by flame atomic absorption after cloud point extraction. Methods The effect of experimental conditions such as pH value and concentration of reagents and equilibration temperature on cloud point extraction and determination sensitivity was discussed. The chemical variables affecting the separation phase and extraction recovery were optimized. Results Under the optimum conditions, pre-concentration of only 50 ml of sample in the presence of 0.05% Triton X-114 presented a detection limit of 0.28 ?g/L(3?) for manganese. The enhancement factor was 65 for manganese. The relative standard deviation was 2.17%. The calibration graph using the pre-concentration system for manganese was linear with a correlation coefficient of 0.999 at levels near the detection limits up to at least 120 ?g/L. The recovery rates were 98.0%-101.5%. Conclusion The method is rapid, accurate, simple and is suitable for determination of trace manganese in water samples.