Production of Rayon from Palm date fronds

Production of Rayon from Palm date fronds


Prepared by:
Prof. Dr. Alaa Kareem Mohammed/

Department of  biochemical engineering, Al-Khwarizmi College of  engineering, University of Baghdad

Teacher Dr. Assim Hassan Mohammed/Central Technical University, Institute of technology, Baghdad
Engineer Yassamin Saleh Mahdi/Babylon

Abstract


The artificial silk (Rayon) was produced from the fronds of date palms, specifically from the two main parts of the frond, namely wicker and blade. The palm fronds were taken and cut into small pieces and converted into a powder of 90-180 micrometers using an electrical mill. Initially, the components of the frond were analyzed and measured. The proportions in the wicker (on dry basis) were as follows: (59% sugar, 25% lignin, 8% extractives, and 8% ash) while in the blade were found to be (62% sugar, 23% lignin, 7% extractive, and 8% ash).  A pretreatment was carried out for the powder to remove the lignin material and reduce its contents to about 5% of the weight, as it was treated thermally using digester. Since the material was treated according to organosolv. The optimal conditions in the pretreatment were found to be 60 minutes time and temperature 185oC, and the ratio of ethanol / water was 50% of the weight, which gave the lignin contain in the sample up to (4%). In the subsequent phase, cellulose polymerization was reduced by treating cellulose fiber with sodium hydroxide solution (17%) at room temperature for 6 hours. Cellulose fiber is then converted to cellulose-alkaline fiber with a polymerization degree of (400- 700) which will facilitate the process of dissolving cellulose in later stages. Carbon disulphide (CS2) was used to dissolve the cellulose fibers after reducing the polymerization level, the color of the viscous liquid change from light yellow to dark orange. The latter dissolves with diluted sodium hydroxide solution (3%) for 1 hour. Finally, the obtained solution was injected with sulfuric acid (6%) to obtain the artificial silk (Rayon).