Ameliah, Reni IrzaPadilYelmida2013-06-292013-06-292013-06-29rio andikahttp://repository.unri.ac.id:80/handle/123456789/3990Production of pulp and paper producing solid waste such as pulp reject the amount of 2.28% of the total production is not fully utilized. Based on its chemical composition, containing alpha cellulose pulp reject (86.738%), hemicellulose (8.342%), lignin (3.17%), extractive (1.75%). Alpha cellulose >92% is used as a propellant material, <92% is used as raw material for the paper industry, industrial fabrics, industrial plastics, paints and adhesives. In this research, enhancing the purity alpha cellulose pulp reject the purification process uses the enzyme xylanase. Changing variables in this study are the temperature and the concentration of xylanase enzyme in the purification process using xylanase enzyme. Variations of temperature (35, 40, 45, 50, and 55°C) and the concentration of xylanase enzyme (2.5, 5, 7.5, 10, 12.5%). The refining process is done on the mass of the sample (pulp reject) 5 grams, volume 125 ml distilled water, purification time 3 hours, pH 5 purification, hot plate stirrer speed of 1.5 mot. The best operating conditions tempetur obtained at 50°C and the concentration of xylanase enzyme 7.5% with a purity of 95.287% alpha cellulose reach.otherReject pulpAlfa celluloseprocess purificationxylanase enzymestudent Paper Post Degree