Sezgin Koray Gülsoy

KRAFT PULPING PROPERTIES OF EUROPEAN BLACK PINE CONE

In this study, different mixtures of cones and wood chips of European black pine (Pinus nigra) were kraft cooked, and the resulting pulp and paper properties were investigated. Also, the chemical compositions and fiber dimensions of the cones and wood were examined. Cone chips were mixed in different ratios (5%, 10%, 15%, and 20%) with wood chips prior to pulping. Also, kraft pulping of 100% cone chips and 100% wood chips were conducted so the results could be compared. The kraft pulp of 100% cone chips had lower pulp yield, lower pulp strength, and higher kappa number than that of 100% wood chips. As the ratio of cone chips was increased in the mixture of cone chips and wood chips, higher kappa numbers and lower total screened yield were obtained. Additionally, the strength properties and brightness of the resulting kraft pulp were decreased gradually. However, the opacity of the pulp was increased slightly. Consequently, cone fibers of European black pine can be used as a raw material in the paper industry by mixing with wood fibers.

Kemijski sastav, morfologija vlakana i sulfatni postupak proizvodnje celuloze od stabljika paprati (Pteridium aquilinum (L.) Kuhn)

In this study, kraft, kraft-NaBH4, and kraft-KBH4 pulp and paper properties of the bracken stalks (Pteridium aquilinum (L.) Kuhn) were determined. Also, the chemical composition and fi ber properties of bracken stalks were evaluated. NaBH4 and KBH4 were separately added to cooking liquor by 0.5 %, 1 %, 1.5 %, and 2 % (oven dried wood). The boron compound-free kraft pulp were also made as control pulp. Fiber length and fi ber width of bracken stalks were determined as 1.25 mm and 24 μm, respectively. Bracken stalks are composed of 73.34 % holocellulose, 32.55 % α-cellulose, and 30.79 % lignin. In addition, the pulp yield was increased with additions of both boron compounds, while kappa number was decreased. Also, highest strength increases determined in 0.5 % NaBH4 added pulp. These results showed that bracken stalks can be used as a raw material for kraft pulp production.

Influence of Some Boron Compounds on Kraft Pulping of European Black Pine and European Aspen

This study investigated the effects of E-48 borax pentahydrate (A), E-67 agro boron (B), and Ground Colemanite (C) on properties of kraft pulp-paper obtained from European black pine and European aspen. The highest screened pulp yield values were determined by adding 8 % B during cooking of both species. The best pulp strength increases were determined by adding 8 % B during cooking of European aspen. Likewise, compared to control samples, the stability of Xylose, Mannose and 4-0-MeGlcA units was increased in European black pine kraft pulp after adding 8 % B. Furthermore, in producing the European aspen pulp, adding of 8 % A during cooking positively affected the total amount of hemicelluloses.