An increase in paper production, as well as stricter environmental protection regulations and the decreasing area of forest per capita may make it difficult to obtain the traditional raw material (i.e. wood) used in papermaking in the future. As a consequence, research aiming to increase fibrous semi-manufactured product yields has focussed on improving the selectivity of wood delignification and stability of polysaccharides, which has led to the development of technology involving the use of polysulphides and anthraquinone, solutions which are said to facilitate more rational wood processing. However, the relatively low increase in pulp yield (2 - 4%) from wood obtained using these methods seems insufficient to overcome the potential shortage of wood raw material facing papermaking