Chemical and statistical characterization of selected documents from the archives of the Palazzo Ducale (Venice, Italy)

A Multi-Analytical Approach for the Evaluation of the Efficiency of the Conservation-Restoration Treatment of Moroccan Historical Manuscripts Dating to the 16th, 17th, and 18th Centuries

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.

Conservation of Moroccan manuscript papers aged 150, 200 and 800 years. Analysis by infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and scanning electron microscopy energy dispersive spectrometry (SEM-EDS)

The preservation of manuscripts and archive materials is a serious problem for librarians and restorers. Paper manuscript is subjected to numerous degradation factors affecting their conservation state. This research represents an attempt to evaluate the conservation restoration process applied in Moroccan libraries, especially the alkaline treatment for strengthening weakened paper. In this study, we focused on six samples of degraded and restored paper taken from three different Moroccan manuscripts aged 150, 200 and 800 years. In addition, the Japanese paper used in restoration has been characterized. A modern paper was also analyzed as reference. A three-step analytical methodology based on infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and scanning electron microscopy coupled to energy dispersive spectrometry (SEM-EDS) analysis was developed before and after restoration in order to determine the effect of the consolidation treatment on the paper structure. The results obtained by XRD and ATR-FTIR disclosed the presence of barium sulfate (BaSO4) in all restored paper manuscripts. The presence of calcium carbonate (CaCO3) in all considered samples was confirmed by FTIR spectroscopy. The application of de-acidification treatment causes significant changes connected with the increase of intensity mostly in the region 1426 cm(-1), assigned to the asymmetric and symmetric CO stretching mode of calcite, indicating the effectiveness of de-acidification procedure proved by the rise of the alkaline reserve content allowing the long term preservation of paper. Observations performed by SEM magnify the typical paper morphology and the structure of fibbers, highlighting the effect of the restoration process, manifested by the reduction of impurities.