The degradation of cellulose is an important factor influencing its mechanical, optical, physical, and chemical properties and, hence, the lifetime of paper in libraries and archival collections. Regardless of the complexity of the paper material, the main chemical pathways for its degradation are hydrolysis and oxidation. This study presents an overview of the analytical techniques employed in the evaluation of the hydrolysis and oxidation processes; these techniques include size-exclusion chromatography, Fourier-transform infrared and ultraviolet–visible spectroscopy, and X-ray diffraction. This paper aims to determine the extent to which these instrumental methods are useful for studying the aforementioned processes and for which lignin contents. It also highlights how atmospheric humidity could affect the cellulose structure in paper containing lignin. It was found that humidity causes significant changes in the cellulose chain lengths and that a high lignin content in paper could suppress some cellulose degradation pathways. This knowledge can be applied to developing strategies and selective chemical treatments preventing the consequences of paper ageing.

This research investigates the effectiveness of micro- and nanofibrillated cellulose (M-NFC) coatings compared to traditional synthetic coatings in enhancing the barrier properties of paper. Papers were coated at various grammages (1.2, 1.8, and 2.9 g/m²) and tested for properties such as hydrophobicity, lyophobicity, and surface smoothness. Paper coated with 2.9 g/m² M-NFC showed water absorbency of 10.5 g/m² and castor oil absorbency of 9.6 g/m², which were lower than for commercially available WBB-coated paper (respectively, 12.2 and 14.8 g/m²). The coatings were evaluated through microscopic analysis and physical testing methods including Cobb and Cobb–Unger absorbency tests and wettability measurements. The results indicate that M-NFC coatings provide a sustainable alternative with competitive barrier properties suitable for short-term use products, showcasing potential reductions in synthetic material usage, especially in food packaging.

Fugitive methane emissions contained in the ventilation air (VAM) from underground coal mines make a significant contribution to the global methane emissions. These methane emissions have a high global warming potential (GWP) and should be mitigated to combat climate change. This study reports on a novel integrated recuperator reactor concept designed to mitigate these low-concentration methane streams using catalytic combustion. The paper analyzes the heat recovery aspects of the novel design and illustrates a computer-aided design approach to system development. Both computational and experimental methods were used in the investigation. The double-spiral counterflow design is shown to be able to eliminate methane from the flow stream with the feed at room temperature. A methodology is illustrated that can be used to determine the operating limits of the proposed recuperative reactor system. This system is suitable for use inside a mine.