Reductive and Oxidative Bleaching of Aged Lignocellulosic Papers: A Comparative Study

With natural ageing, wood pulp papers acidify, yellow and become very fragile, all of which pose a major preservation challenge. Bleaching is a remediation treatment primarily used to increase the brightness of paper, thereby enabling access to its historical or artistic content. Literature on paper bleaching is vast and the lack of standardised protocols makes it difficult to compare the results. Moreover, these studies often focus on papers containing no or little lignin. To tackle these issues, we compared the impact of reductive and oxidative bleaching on two naturally aged lignocellulosic papers' color, pH, water absorption and mechanical strength.