The usage of high ash content biomass for heat and electricity generation may lead to various ash-related problems, primarily to heating value, ash and combustion characteristics. The study aims at studying the effectiveness of leaching on removing ash forming elements and increasing ash melting temperature using water and acetic acid as the extraction agent. Leaching by acetic acid solutions removed most of the ash forming elements, with ash melting characteristics under high temperature were considerably improved. If the ash removal efficiency and HHV were to be taken as consideration for the selection of leaching treatment, acetic acid leaching method will be the most preferable treatment. Using the method established in this research, the lignocellulosic biomass presented in this study can be prepared for combustion with the assurance that ash forming elements have been reduced sufficiently to safeguard against ash production, corrosion and slagging in biomass boiler. (C) 2015 Elsevier Ltd. All rights reserved.