Cultural heritage in museums, galleries, and other institutions, where historical objects
are stored, is subject to gradual degradation due to the presence of volatile organic
compounds (VOCs). Objects made of various materials such as metals, minerals, glass,
paper, dyes, etc., are at risk. The highest concentration of VOCs is found in enclosed
spaces such as display cases, cabinets, drawers, etc. The primary source of pollutants is
wood, which mainly emits formaldehyde, acetic acid, and formic acid. Due to the increase
in new materials, besides these three, other pollutants are also present in the museum
atmosphere, whose problematic effects are not yet known. Due to the increasing
vulnerability of objects, numerous studies are focused on investigating the sources,
concentrations, and problematic effects of corrosive compounds. Additionally, research
is also directed towards preventing the occurrence of high concentrations of VOCs in the
presence of historical objects. There are various options, including the use of building
materials that bind compounds, the use of furniture materials that emit fewer problematic
compounds (e.g., metals and glass), room ventilation, sealing of enclosed spaces, etc. One
of the options to prevent a significant increase in pollutant concentrations in small and
tightly enclosed spaces is the use of so-called sorbents. These substances primarily bind
compounds through physisorption. The goal of my master's thesis was to characterize ten
sorbents that could potentially be used for the protection of cultural heritage. I was
interested in whether the tested sorbents were suitable to be located near historical objects,
as the sorbents themselves could emit pollutants that could be corrosive. The composition
of nine sorbents was unknown, with activated carbon being the only known sample, which
is one of the most common sorbents. Therefore, I expected it to be useful and nonproblematic in my case, which was confirmed by experiments. I assessed the suitability
of the sorbents using the Oddy test, an accelerated corrosion test that, under conditions of
100% relative humidity and a temperature of 60 °C, indicates whether a certain substance
releases compounds that could corrode lead, silver, or copper. I was also interested in
identifying the compounds that could cause corrosion in these three metals and the
composition of the sorbents. Therefore, I performed solid-phase microextraction
sampling, where I exposed the sorbents placed in vials to heating in a water bath at 60 °C.
I identified the sampled compounds using gas chromatography/mass spectrometry. It
turned out that all the unknown sorbents, which appeared as white crystalline substances,
emitted (cyclic) organic nitrogen compounds. Comparison with the mass spectrometry
library also showed that all of these sorbents likely emit the compound acetaldoxime. By
comparing the areas of chromatographic peaks among different samples, I found that the
sorbents emitting the most acetaldoxime fail the Oddy test, as they corrode copper. I
attempted to further correlate the findings obtained from the Oddy test and GC/MS
analysis by using IR spectroscopy of metal plates from the Oddy test.
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