37 Review on the various ash from palm oil waste as geopolymer material l SeP]RTSE cdSh T]cTaA"cS Rev. Adv. Mater. Sci. 34 (2013) 37-43 Corresponding author: Yahya Zarina, e-mail: zarinayahya@unimap.edu.my REVIEW ON THE VARIOUS ASH FROM PALM OIL WASTE AS GEOPOLYMER MATERIAL Y. Zarina 1 , A. M. Mustafa Al Bakri 1 , H. Kamarudin 1 , I. Khairul Nizar 2 and A. R. Rafiza 1 1 Center of Excellence Geopolymer and Green Technology, School of Materials Engineering, Universiti Malaysia Perlis (UniMAP), 01007, P.O. Box 77, D/A Pejabat Pos Besar, Kangar, Perlis, Malaysia 2 School of Environmental Engineering, Universiti Malaysia Perlis (UniMAP), P.O. Box 77, D/A Pejabat Pos Besar, 01007, Kangar, Perlis, Malaysia Received: September 09, 2012 Abstract. The solid waste from palm oil mill industry has been increasing annually where it has been reported that the palm oil waste was produced 4 million tons/years in Malaysia only. Hence, the solution to overcome the problems is to reuse the waste and produced new composites that are benefit. There are two types of palm ash waste which are palm oil fuel ash (POFA) and boiler ash. POFA is by product from power electricity generation plants that used palm oil shells and palm oil bunches as burn materials. Meanwhile boiler ash is the biomass known as mesocarp fiber and shell that consists of clinkers and ash that has been burnt in the boiler. Both of these ashes contain silica (Si) which has potential to develop as geopolymer composites. However, only POFA has been successfully produced ash geopolymer materials but it required other raw material that rich in alumina (Al) to produce geopolymer with suitable strength. In order to produce geopolymer, the POFA has been activated by alkaline activator consists of mixture of sodium silicate (Na 2 SiO 3 ) and sodium hydroxide (NaOH). On the other hand, the use of boiler ash as geopolymer materials was never been investigated. 1. INTRODUCTION In recent years, various researchers were concentrated on producing environmental friendly products such as geopolymers. The production of geopolymers required alumina-silicate based materials which are rich in silicon (Si) and aluminum (Al), where it was activated by alkaline solutions [1]. The most alumina-silicate based materials that has been explored in the production of geopolymers were fly ash [2-4], metakaolin [5] and kaolin [6-8], palm oil fuel ash (POFA) [9], combination of ground granulated blast furnace slag (ggbs) and metakaolin [5], combination of fly ash and metakaolin [10-11], combination of POFA and metakaolin [12], combination of POFA and fly ash [9]. As result from the previous researches it was prove that geopolymers have excellent mechanical properties, high resistance to chemical attack and also abilities to encapsulate hazardous waste [13-15]. Moreover, there are potential applications of geopolymer as fire resistance panel [16] or as fire resistant coatings on metal [17]. The large production of palm oil in Malaysia has made it become the second largest oil palm producer in the world on 2010; where 18.6 million metric tons production has been made [18]. However, waste from the palm oil industry also abundantly produced which caused criticism and complaint. The waste such as palm fibers, nut shells, palm kernel and empty fruit bunches are the solid waste the obtained from palm oil processing for oil extraction. Furthermore, these wastes were incinerated in boilers and from