Comparing Four Methods for Purifying Date Fibers for Reinforcement Purposes in Biocomposites

During the past two decades the use of lignocelluloses fiber for biocomposite production has been the focus of many investigations. In order to reduce the lignin and hemicelluloses of the crude fibers, the fibers are often treated with different chemicals. The chemical treatments should enhance the physical and mechanical properties of the fibers and increase the adhesive force between the matrix and the biofibers. In this research, NaOH, KOH, and HCl were used in different concentrations for purifying date tree fibers. The percentage of pure fiber, ash content, coefficient of friction, diameter, and the tensile strength of the fiber prepared by different treatments were determined and statistically compared. The Weibull distribution model was used to investigate the variation in tensile strength of the fibers. The results indicated that the purification methods decreased the lignin content between 20 to 50, the ash content from 37 to 75% and the diameter of the fibers between 37 to 62%. The tensile strength of the fibers increased between 15 to 60%. The Weibull analysis of the data indicated that the distribution of tensile strength in purified fibers was more uniform than the untreated fibers.