A column solid phase extraction (SPE) and preconcentration method was developed for the determination of Fe(III) ion in aqueous samples by flame atomic absorption spectrometry. The method is based on sorption of Fe(III) ions on natural Analcime Zeolit column modified with a new Schiff base, 5-((4-nitrophenylazo)-N-(2′,4′-dimethoxyphenyl))salicylaldimine (L), and then eluted with 0.1 M EDTA and determined by FAAS. Various parameters, such as the effect of sample pH, flow rate, volume of the sample and interference of the metal ions on the method, to optimize the conditions for determination of Fe(III) ions in aqueous samples, were studied. The recoveries were >99%. The developed method was applied to the determination of trace Fe(III) ions in drinking water and river water samples with satisfactory results.

Microwave-assisted distillation (MAD) is a combination of microwave heating and dry distillation at atmospheric pressure in which isolation and concentration of volatile compounds are carried out, simultaneously without solvent or water. The aim of this work is to evaluate the performance of MAD when isolating the essential oil of Rosa damascena Mill. For this purpose, first, two main parameters, namely extraction time and microwave power, which affect the efficiency of the extraction, were optimized. Then, to demonstrate the feasibility of the method, oil obtained under optimal conditions was compared quantitatively and qualitatively with that obtained by conventional hydrodistillation (HD) using an electric mantle heater. Considering the extraction yield, optimal extraction time and microwave power were obtained to be 15 minutes and 650 W, respectively. Extraction of essential oil from rose flowers with MAD offers important advantages over traditional HD in terms of energy saving, extraction time (15 minutes versus 3.5 hours) and extraction yield (0.037% versus 0.018%). However, there is a significant decrease in monoterpene alcohol percentages and increase in hydrocarbon percentages, which is a disadvantage from qualitative point of view.