Removal of Copper (II) from Aqueous Solution using Dolomite as New Geopolymer Adsorbentbased Alkali Activated Material

This study evaluates the effectiveness of dolomite as the primary material in geopolymer adsorbent for removing copper ions from aqueous solutions. Dolomite is an alkali-activated material (AAM) known for its ability to adsorb harmful elements like copper ions in wastewater, thanks to its distinctive composition and structure. This material is considered a cost-effective adsorbent due to its abundance and global availability. However, there is limited research on using dolomite as an adsorbent to eliminate heavy metals from wastewater, and no studies have explored producing dolomite as the primary material for geopolymer adsorbents. The aim of this study is to assess the effectiveness and capabilities of dolomite in producing a high-quality geopolymer adsorbent based AAM for adsorbing copper ions. Otherwise, this material was examined for characterization techniques using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) to analyse the structural and morphological changes for synthesizes geopolymer. Various parameters, such as the solid-to-liquid ratio (2, 2.5, 3) and the alkali activator ratio (1.5, 2, 2.5, 3), influenced the removal efficiency. The results showed that dolomite based geopolymer adsorbent demonstrated superior removal performance compared to raw dolomite. The highest copper ion removal efficiency was achieved with a solid-to-liquid (S:L) ratio of 2.5 and an alkali activator ratio of 2.5, resulting in a removal efficiency of 46.92% and an adsorption capacity of 181.33 mg/g. The Langmuir isotherm provided a more accurate fit than the Freundlich isotherm, indicating a monolayer adsorption on the surface. The results showed that dolomite may effectively be used as a geopolymer adsorbent to remove copper ions from wastewater.