Preparation of amorphous oil palm frond ash (OPFA) via acid leaching treatment as precursor for silica synthesis

Abstract

Oil palm frond (OPF) was investigate in this study that aim to establish the potential of OPF as precursor for silica synthesis. OPF is one of abundance biomass produce in oil palm plantation during pruning and replanting phase that usually underutilized comparable to other oil palm-based waste. In this study, OPF was first combusted at 600 ℃ to produce the oil palm frond ash (OPFA) that subsequently followed with acid leaching treatment using 3% citric acid solution. The non-leached ash and leached ash was analysed and characterized using Fourier Transform Infrared Spectroscopy (FTIR) and AAS Atomic Absorption Spectroscopy (AAS). Combustion of OPF indicate that it produces approximately of 3.5% of ash out of total weight of OPF. The AAS analysis perform display a significant reduction of metal ions such as K+, Ca+ and Mg+ and total removal of iron from which proven the beneficial of acid leaching treatment in removing the undesired substance from OPFA. FTIR characterization display a significant different in spectra of treated and non-treated ash and it also successfully illustrate that the OPFA produce contain the required silica as well as the acid leached OPFA is in amorphous form due to the absence of band which indicating the presence of tridymite (crystalline phase).