ACIDITY, SOLUBILITY AND CHEMICAL UTILIZATION OF LOCAL LEUCAENA LEUCOCEPHALA STEM BARK

Abstract

Acidity, solubility and chemical properties of eleven years old of Leucaena leucocephala stem bark were investigated. The bark was peeled from the stem of tree and gentle washed in tap water to remove dirt before air-dried in the laboratory at room temperature (24 + 3°C) for 2-3 weeks. The bark was minced into coarse powder and grind to pass BS 250μm mesh sieve. After air-dried for several days, the samples were conducted to chemical analyses (ash content and pH value; solubility in 1%NaOH, hot and cold water solubility; extractive, cellulose and lignin content) based on ASTM standard methods. The results show that L. leucocephala stem bark considered as least acidic (pH value 6.04) and high ash content (15.76%). The solubility of bark components was higher in 1% NaOH (41.36%) compared to hot water (14.45%) and cold water (11.06%). Holocellulose and hemicellulose was 132.85% and 103.66%, respectively. Lignin was the major composition in L. leucocephala stem bark (38.4%) followed by cellulose (29.19%) and extractive (8.39%). This study indicated that the bark of L. leucocephala had less acidity. The high solubility of the bark potential as a carbohydrate resource, while the chemical component of the bark might influence rapid combustion during pyrolysis.