Tetraethylene glycol thermooxidation and the influence of certain compounds relevant to conserved archaeological wood

摘要

The degradation of tetraethylene glycol (TEG) was studied at 70 °C under dry air and nitrogen. Degradation products were detected using gas chromatography-mass spectrometry (GC-MS). They were mono-, di- and tri-ethylene glycol, mono- and di-formates of mono-, di-, tri- and tetra-ethylene glycol and formic acid. The rate of TEG degradation was significantly decreased by approximately 10 mmol/l KI, FeCl_3, Cu(CH_3COO)_2, MnO_2 and CuSO_4, small amounts of fresh oak wood sawdust and gypsum-containing scrapings from the wood surface of the Vasa ship in Stockholm. Thus certain salts and natural components of archaeological wood are able to inhibit oxidative degradation of TEG. NaFe_3(SO_4)_2(OH)_6 (Natrojarosite), FeS_2 (pyrite), FeSO_4, Fe_2(SO_4)_3, NiCl_2, NiSO_4, Fe, Cu, Fe_2O_3, CuO, NaHSO_4 and natrojarosite-containing scrapings from the Vasa had no major effect on the rate of oxidation.