Pengaruh Delignifikasi Termal Terhadap Substansi Dinding Sel Pada Limbah Bunga Jantan Kelapa Sawit Pasca Anthesis (The Influence of Thermal Delignification of Cell Substantials for The Waste of Oil Palm Mail Flowers Post Anthesis)
 The oil palm male flowers post anthesis is one of the solid wasted of oil palm which has not been much utilized. It can be used by processing into biofuel or bioethanol and to be alternative for fossil fuels whose availability is increasingly scarce. The purpose of this study were to determine the effect of several cycles of thermal delignification on the levels of lignin, holocellulose, and cellulose and to determine the best levels of lignin, holocellulose, and cellulose from the treatment of several thermal delignification cycles. This study used a one factor completely randomized design method with 3 treatments; one, two, and three cycle thermal delignification. Each treatments were three replications. Data were analized with analysis of variance with α 5 %, if there was a significant treatment effect, the further analysis using Tukey test. The results showed that the treatment of thermal delignification with several cycles had a significant effect on the levels of lignin, holocellulose, and cellulose. The best levels of lignin, holocellulose and cellulose were shown in the treatment of three cycles of thermal delignification.Keywords: bioethanol, cellulose, hemicellulose, holocellulose, lignin