Majallah-i Chughundar-i Qand (Feb 2012)
Optimization of cellulose extraction from sugar beet pulp
Abstract
Cellulose is a raw material which is extensively used in the manufacture of paints, papers, textiles, agricultural products and cosmetics. The waste of sugar beet pulp after titration is a source of cellulose. The current study was carried out to study the possibility of cellulose production from sugar beet pulp waste at titration stage as a 3×3×2 factorial study on the basis of a Randomized Complete Block Design with three replications. So, firstly the waste of titrated sugar beet pulp was collected, washed, dried and ground. Then, the ground sample was hydrolyzed by hydrochloride acid 0.6 N at 45°C for 48 hours and was mixed with water at 70°C for one hour in order to isolate dissolved pectin and pectic compounds. Then, the remaining waste was washed, dried and treated with soda solution with the ratio of 1 g waste:100 ml soda solution at three levels with the concentrations of 2.5, 5 and 7.5% (w/v) at three lengths of soda impact including 8, 10 and 12 hours and two levels of temperature of soda impact including 24 and 45°C in order to isolate the basic medium-dissolved polysaccharides from cellulose. The measured traits included relative purity, viscosity and cellulose molecular mass. Results showed that the effect of soda concentration and stirring length as well as their interaction was significant on relative purity at 5% probability level. In addition, it was revealed that out of the studied treatments, the cellulose extracted through treating with 5% soda stirred for 12 hours at 45°C had significantly higher quality given that it enjoyed 95.2% relative purity, 15.9 mPa.s-1 viscosity and 255000 kg.mol-1 molecular mass which were significantly higher than those of other treatments. Therefore, this method allows extracting cellulose with 95.2% relative purity from sugar beet waste.
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