Spent Bleaching Earth as Value-Added Material to Material Construction Applications: A Review

Abstract

Crude palm oil (CPO) serves as a significant export commodity for Indonesia, contributing positively to the country's economic growth and generating income for communities. Nonetheless, the production of CPO results in an environmental drawback in the form of refined, bleached and deodorised (RBD) palm oil, which poses environmental concerns. One pivotal material used in the purification process to transform the reddish-orange CPO into a lighter yellow hue is known as bleaching earth. As a consequence, a substantial amount of waste, referred to as spent bleaching earth (SBE), is generated and recovered to prevent harm to the environment. Remarkably, research has revealed that SBE exhibits pozzolanic properties, rendering it suitable for incorporation into construction materials. The primary objective of this study is to emphasize the advantages of integrating SBE into the construction material manufacturing process. Mixtures containing eco-process pozzolan (EPP), the product derived from SBE, have exhibited superior strength characteristics when compared to mixtures using ordinary portland cement (OPC). Furthermore, concrete incorporating pozzolan mixtures has displayed increased strength values when subjected to high temperatures, outperforming concrete made exclusively with OPC. However, further investigation is required to ascertain the thermal resistance capabilities of EPP as a component in mortar or concrete.