WOOD RESEARCH Volume 61, Number 6, 2016
Birol Üner, Kenan Kömbeci, and Mehmet Akgül

The utilization of tomato stalk in fiber production: NAOH and CAO pulping process

This study was conducted to explore the utilization of tomato stalk in the paper industry. Fiber morphology of the material was determined according to standard test methods and average fiber length was found to be 980 μm and the width of the fiber was 15 μm. As a result, slenderness ratio was resolved to be around 60. This was considered to be comparable fiber with the most of the hardwood species. Tomato stalks were cooked with soda and lime in a separate process. Screened pulp yield was determined to be 35-45 %. Soda pulp of tomato stalks showed good mechanical properties when temperature raised to 135ºC and low alkali concentration (10 %) and lime pulps showed properties as well as that soda pulp at 135ºC and high alkalinity ratio (30 %).

WOOD RESEARCH Volume 61, Number 1, 2016
Birol Üner, Mehmet Akgül, M.Onurhan Gücüş, and Serkan Demir

The effect of oxalic acid pretreatment on alkali pulping process

The objective of this study was to determine prehydrolysis process on kraft and soda pulping process. Optimum cooking conditions were determined by different alkali concentration and cooking period. Oxalicacid was used to hydrolyzechip before cooking. Prehydrolysis proces increased the yield and viscosity of pulp. Incontrast, mechanical properties of paper were not changed significantly. Optical properties were decreased due to lignin content.

WOOD RESEARCH Volume 62, Number 4, 2017
Mehmet Akgül, Birol Uner, Osman Çamlibel, and Ümit Ayata

Manufacture of medium density fiberboard (MDF) panels from agribased lignocellulosic biomass

Lignocellulosics fibers and commercially-manufactured-chip (Pinus sylvestris L., Fagus orientalis and Quercus robur L.) with 11% moisture conten twere used for the experiment. The mixingratios of lignocellulosics fibers was 20% which is from okra and tobaccos talks, hazelnut and walnuts hell, and pinecone for each mixture in preformed panel and commercially-manufactured-chip was 100 % for the control sample. A commercial ureaformaldehyde (UF) adhesive was used as a binder. The physical and mechanical properties such as density, thickness swelling (TS), bending strength (BS), modulus elasticity (MOE), internalbond (IB), screw holding ability (SHA) perpendicular to the plane of panel, Janka hardness perpendicular to the plane of panel properties of MDF were measured.The results indicated that all the panels met the general purpose-use requirements of TS-EN. Thus, our results suggest that biomass from different sources can be an alternative raw material for MDF manufacturing process.