Comparative study on Pulping characteristics of Carpinus betulus and Parotia oersica woods

Abstract

In this investigation some anatomical, chemical and pulping suitability of two Iranian hardwood species which predominate in the Caspian forests were examined. The species are carpinus betulus (Hornbeam) and parotia persica (Ironwood).The results of this study revealed that:The average fiber length of carpinus betulus is 1.4 mm., fiber diameter 18 mm, and cell wall thickness 3.37 mm, while inparotia persica, fiber length, cell diameter and cell wall thickness are 1.34 mm, 17.3 mm and 3.48 mm respectively.The overall average of cellulose content: of carpinus betulus and Parotia persica were measured at 48.5, and 46.1 percent, and the lignin content at 17.5 and 21.5 percent respectively.The wood of each of the above species was cooked by means of a kraft process without difficulty but, there was a slight decrease in yield and kappa number with increase active alkali.The pulping yield with active alkali of14% was about 49.6 and with 20% was 43.44 percent, while the pulping yield of parotia persica in active alkali of 14% was 43.04 and in 20% about 37.79 percent. Thus, it may be concluded that for production of wrapping paper from carpinus betulus and parotia percica, using active alkali of 14% might give better quality paper and for production of printing paper from these two species active alkali of 20 percent might be desirable.

Keywords

• Carpinus betulus
• Parotia oersica
• anatomical
• chemical and pulping suitability