The preliminary research on the photocatalytic degradation of methylene blue by using laterite ore from Indonesia

Indonesia has a large amount of laterite ore deposits. The high-grade laterite has been processed to produce ferronickel for stainless steel fabrication, whereas the low-grade laterite cannot be used to produce the ferronickel. The laterite ore consists mainly of goethite (FeOOH), antigorite (Mg48Si34O147H79), and quartz (SiO2). The existence of iron makes laterite a candidate raw material for photocatalyst synthesis. The preliminary research on photocatalyst material synthesis by using laterite ore has been conducted in our research group. The laterite ore was leached in chloric acid solution and then sodium hydroxide was added into the leaching solution to precipitate iron oxide from the leaching solution. The reaction happening during leaching and precipitation was analyzed. The iron oxide was used as photocatalytic material to degrade methylene blue, as the representation of organic waste. Leaching time and the addition of hydrogen peroxide were the observed variables. The preliminary result shows that the % degradation of methylene blue by using only this iron oxide is 16%. The addition of hydrogen peroxide results in an increase in % degradation by up to 48%.