Rubber wood ash (Havea Brasiliensis) characteristics as a potential geopolymer cement material

The solid waste of rubber wood ash (Havea Brasiliensis), a byproduct of the rubber industry combustion process, has not been effectively utilized to become a product with economic value. Silica-rich industrial and agricultural byproducts such as fly ash, rice husk ash, bagasse ash, and wood waste ash have been extensively researched for use in geopolymer mixtures for several decades. The purpose of this research is to characterize rubber wood ash solid waste raw material, which has the potential to become raw material mixtures for geopolymer cement. The structure and compounds contained in rubber wood ash were determined using XRD and XRF instruments in this study. Then, identify the process parameters that influence the geopolymer cement process, such as sodium hydroxide (NaOH) as an alkaline activator with different concentrations and temperatures, on geopolymer cement compressive strength value. Geopolymer cement was developed in this study by mixing rubber wood ash, NaOH at concentrations of 8M, 12M, and 16M, and sodium silicate (Na2SiO3) in a 1:2 ratio. The product was then cast in a 5x5x5 cm cube mold and dried at room temperature for 24 hours before being heated up for 8 hours at 30°C, 60°C and 90°C. After that, the compressive strength of geopolymer cement will be tested after 28 days of curing time. The concentration of alkali activator (NaOH) and geopolymer cement products will then be determined under best conditions. The potential of rubber wood ash as a raw material for geopolymer-based cement can be carried out.