COMPARISON BETWEEN MICROWAVE AND CONVENTIONAL HEATING PROCEDURES IN TESSIERS EXTRACTIONS OF CALCIUM, COPPER, IRON AND MANGANESE IN A LAGOONSEDIMENT

The results of Tessier's extraction of calcium, copper, iron and manga nese in sediments using conventional and microwave heating were compar ed. The metals were determined by atomic absorption spectrometry with flame and electrothermal atomization. Magnesium chloride (extractant o f exchangeable fraction) was replaced with ammonium acetate. Sediments collected from the Venice lagoon were analysed. The results showed th at microwave heating produces results comparable to those of conventio nal heating with a much shorter operating time.