Investigation of complexation and solid-liquid extraction of iron from paper by UV/VIS and atomic absorption spectrometry

The aim of this study was to evaluate the strategy for the investigation th e possibility of diminishing the iron-gall ink corrosion process occurring often in ancient manuscripts. In order to understand the respective process es, the efficiency of iron complex formation as well as solid-liquid extrac tion of iron compounds from the paper was investigated by UV/VIS spectromet ry and by graphite furnace atomic absorption spectrometry (GFAAS) as well. Acetylacetone, dibenzoylmethane and deferoxamine mesylate were chosen as th ey are known to form strong complexes with iron and they exhibit a broad ab sorbance band in the range of 390-600 nm. UV/VIS spectrometry was used for the determination of that part of iron, which was bound with the respective complexing agent. Parallel, the total amount of iron in the solution was m easured by GFAAS. The efficiency and rate of the process were investigated for FeCl3 as well as for iron compounds present in the iron-gall ink soluti on. It was demonstrated, that the process is based on the fast extraction o f the iron from the paper followed by the iron-complex formation in the sol ution.