Comparison of iron deposits removing material from the marine archaeological wood of Nanhai I shipwreck.

• Iron deposits in Nanhai I shipwreck wood were hydroxyl iron oxide and pyrite. • Near-neutral DTPA and amidoxime cellulose had high iron deposit removal efficiency. • Na 2 S 2 O 4 improved the iron deposits removal efficiency of EDTA-2Na. Iron deposits are commonly found in marine archaeological wood, causing acidification, degradation, and mechanical damage to marine archaeological wood. This study focused on extracting iron deposits from loose wood samples taken from the Nanhai Ⅰ shipwreck. The removal efficiency of iron deposits in wood using materials, such as EDTA-2Na, DTPA, C 6 H 17 N 3 O 7 , Na 2 C 2 O 4 , amidoxime cellulose, DFO, EDTA-2Na-H 2 O 2 , DTPA-H 2 O 2 , EDTA-2Na-Na 2 S 2 O 4 , and DTPA-Na 2 S 2 O 4 , was evaluated. Analysis using scanning electron microscopy/energy dispersive spectroscopy and X-ray diffraction identified the presence of iron deposits in the wood of the Nanhai I shipwreck including goethite (FeOOH) and pyrite (FeS 2). The removal efficiency was evaluated by ICP-AES and results showed that amidoxime cellulose and DTPA had higher removal efficiency for iron deposits in wood. The difference between the iron deposits removal efficiency of DTPA and EDTA was significant after the addition of oxidant (H 2 O 2) and reductant (Na 2 S 2 O 4) to the systems, respectively. The addition of oxidant H 2 O 2 to DTPA improved the iron deposits removal efficiency of DTPA from wood within 30 days. Furthermore, the addition of reductant Na 2 S 2 O 4 to EDTA-2Na significantly improved the iron deposits removal efficiency of EDTA-2Na from wood. These findings provide a valuable reference for developing efficient methods for removing iron deposits during the practical protection of the Nanhai I shipwreck. [ABSTRACT FROM AUTHOR]