SILIKA GEL DARI ABU TERBANG (FLY ASH) PEMBANGKIT LISTRIK TENAGA UAP (PLTU) (Menentukan Waktu Optimum Untuk Mendapatkan Hasil yang Terbaik )

Power stations produce vapor of solid waste in the form of ashes flying coal.Ashes flying this has not been well taken advantage while these flying ash having silica levels high enough namely 36,51 %.The high silica content allows abu it can be used as a source of silica in the manufacture of silica gel. This research aims to extracting ashes flying this by using a solvent naoh on temperature and a time that varied namely 120 -1400C during the 2 hour and of three hours The extraction of this results in the form of a solution of sodium silicate that next neutralized his pH by using HCl 5M. Simultaneously with a solution of sodium neutralization silica gel-gel happened the formation of silica. So formed precipitate silica gel who then filtered and oven during the 2 hour till silica gel almost not having the water level.After product oven silica gel absorption done testing the water level in the room humid for 6 hours. Silica gel products are best obtained on temperature and 1300C time in 3 hours with % rendemen 35,7 with purity 37.8 % and absorption capacity 36 % of testing water absorption capacity silica gel resulting have met the standards JIS 0701 . Keywords: silica, silica gel, fly as