The present work is focused on spectroscopic study of four samples of Argan wooden artifact pertaining to the 17th, 18th, 20th and 21st centuries. The objective is to characterize their unknown structures by the study of their non degraded parts and to investigate changes occurred in their degraded parts due to the natural degradation process. Attenuated total reflectance Fourier transform infrared spectroscopy gauges the presence of many functional groups related to cellulose I and/or II (OH, C–O–C and –CH2), hemicelluloses (particularly C=O acetoxy ester band at 1732 cm−1), and lignin (OH phenolic, Car-O and C=Car) and provides qualitative information on the state of wood alteration by informing on the evolution of new former C=O bands. The degree of conversion to carbonyl group, especially quinone or p-quinone at 1650 cm−1, is correlated to lignin degradation, while the absence of the C=O acetoxy absorption is ascribable to occurred deterioration in hemicelluloses, and partial degradation of cellulose with enhancement of the C=O region between 1730-1630 cm−1. X-ray diffraction determines the presence of two forms of cellulose; amorphous cellulose at 18.5° 2θ and predominant crystalline cellulose Iβ at 2θ = 22.6° which characterized by an intense peak. The decrease of crystallinity index values confirms the deterioration level and obvious changes in crystallinity level. However, the microcrystalline structure appears unaltered because no significant changes were observed for calculated cristallite seize. The obtained results depend on the prolonged time of ageing, natural deterioration phenomena, and wood part (internal or external) that is exposed to degradation. The combination of these two methods is useful for an accurate estimation of the degradation level of argan wood.

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Supercritical fluid extractions (SFE) from BAL 150 asphaltenes were achieved with carbon dioxide as solvent under various experimental conditions (pressure, temperature, extraction time, and presence of cosolvent). SFE yields were between 5 and 12% of total asphaltenes. Extracts contained mainly linear alkanes (with chain lengths ranging from C14 to C30), various branched alkanes, and a multitude of complex branched and cyclic alkanes as shown by the GC/MS chromatograms. Many aromatic hydrocarbons, heteroaromatic compounds and their methyl derivatives, and polar compounds were also extracted. The best balance between rapid and efficient extraction was obtained for an extraction time of 60 min. Within the range of the study (40−50 °C), the temperature did not show a marked influence upon the extraction efficiency. Pressure and presence of cosolvent appeared to be the major parameters. Increasing pressure (from 130 to 300 bar) yielded to preferential extraction of heavy n-alkanes, more branched and cyclic alkanes, and aromatics. The comparison of extractions performed with or without cosolvent (toluene and dichloromethane) under the same conditions of time and temperature showed that heavier n-alkanes, more highly branched alkanes, and complex cyclic alkanes (biomarkers) were recovered with modifiers.

The most critical steps during the conservation-restoration treatment applied in Moroccan libraries are the deacidification using immersion in a saturated aqueous calcium hydroxide (Ca(OH)2) solution and the consolidation of degraded manuscripts using Japanese paper. The present study aims to assess the efficiency of this restoration method using a multi-analytical approach. For this purpose, three ancient Arabic Moroccan manuscript papers dating back to the 16th, 17th, and 18th centuries were investigated to characterize the paper support and make a comparative study between pre-restoration and post-restoration states. Three structural and molecular characterization techniques including solid-state nuclear magnetic resonance spectroscopy on (13)C with cross-polarization and magic-angle spinning nuclear magnetic resonance ((13)C CP-MAS NMR), attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT-IR), and X-ray diffraction (XRD) were used to elucidate the cellulose main features, to identify the inorganic composition of the papers, and to study the crystallinity of the samples. Inductively coupled plasma atomic emission spectrometry (ICP-AES) allowed us to obtain a qualitative and quantitative characterization of the mineral fillers used in the manufacturing of the papers. Scanning electron microscopy coupled to energy dispersive spectrometry (SEM-EDS) ascertained the state of conservation of the different papers and helped us to study the elemental composition of the samples. After restoration, it was shown that the deacidification improved the stability of papers by providing an important alkaline buffer, as demonstrated using FT-IR and energy dispersive spectrometry (EDS) results. However, XRD and ICP-AES did not confirm the pertinence of the treatment for all samples because of the unequal distribution of Ca on the paper surface during the restoration. The consolidation process was studied using SEM analysis; its effectiveness in restoring torn areas was found to be significant.