Paper Title
Influence of Chemical Properties, Fiber Morphology and Biometry of Ten (10) Nigeria Cultivated Agro-based Fibers on Properties of Paper-pulp
Abstract
This paper studied the chemical composition, morphological properties and biometry of Ten samples of Nigeria-grown agro-based fibers such as Empty Fruit Bunchof Oil Palm (EFB), Rice straws, Wheat straws, Sugar cane bagasse, Corn stalk, Lemon grass, Elephant grass, Coconut fruit bunch, Pineapple leaves, and of course KenafBast (Hibiscus cannabinus) as reference.Parameters investigated include some chemical properties such as% moisture, 1% caustic solubility (%), hot water solubility (%), extractives (%), holocellulose (%), α-cellulose (%), lignin (%),(%) ash contents, some morphological properties such asfiber length, fiber width, lumen diameter, fiber wall thickness and some morphological indices such as slenderness ratio, flexibility ratio, runkel ratio and rigidity coefficient. The results revealed that there were significant differences among the agricultural residues in chemical composition, morphological properties and biometry. Apart from kenaf, the reference material, the greatest proportion of fiber length (1.70 mm) and alpha-cellulose (59.30%) were found in residues of bagasse, with a low ash (0.8%) and lignin (19.5%). However, amongst the agricultural residues investigated, Oil palm EFB is highest in moisture content and considerably higher than wheat and rice straw in lignin content. Both cold and hot water extractives were much higher for EFB and CFB than for Kenaf (Hibiscus cannabinus), bagasse and other agricultural residues investigated in this research study. It means EFB and CFB would require a slightly higher concentration of pulping liquor to neutralize acidic extractive, which may affect the pulp yield adversely but create less digester corrosion caused by extractives. Results of these studies also shows that the extractive content in rice was 7.90% and was higher than those found in most of the agricultural residues. The extractive content was noted not to be higher than EFB of Oil Palm (13.65%). However, lemon grass (16.89%) recorded the highest extractive content amongst all the agro-based fibers investigated. This indicated that lemon grass, EFB, rice straw, coconut, and sugar cane bagasse contained more substances like waxes, fats, resins, phytosterols, non-volatile hydrocarbons, low-molecular-weight carbohydrates, salts and other water-soluble substances. A higher content of extractives would be converted into pitch, which would adversely affect the runnability of process equipment and the quality of paper, because of shadow marking. Papers made from this type of fibers might show reduced water absorbency. The higher the lignin content, the greater the stiffness of fibers. Klason lignin contents in Kenaf (14.70%) and wheat straw (12.30%) were much lower than those in EFB, sugarcane baggase, rice and coconut. In practice, this means that these materials would need milder pulping conditions (lower temperatures and chemical charges) in order to reach a satisfactory kappa number. They would also undergo bleaching more easily and with the utilization of fewer chemicals.
Keywords - Agricultural residues, Runkel ratio, EFB, Pulp, TAPPI, Slenderness ratio, Lignin