Dye contamination in wastewater presents a significant environmental challenge, necessitating effective and economical remediation strategies. This study investigates the removal of C.I. Basic Yellow 40 dye from aqueous solutions using three low-cost inorganic adsorbents: eggshell powder, hematite powder, and granite powder. Batch adsorption experiments were conducted to assess the effects of contact time, adsorbent dose, and dye removal efficiency. The adsorption behavior was analyzed using Langmuir and Freundlich isotherm models, with hematite powder exhibiting the highest maximum adsorption capacity in the Langmuir model. Kinetic studies using pseudo-first-order and pseudo-second-order models suggested that the latter provided a better fit, indicating chemisorption is the rate-limiting step. Isotherm analysis reveals that monolayer adsorption occurs. This comparative study provides insights into the potential of these readily available materials as cost-effective alternatives for dye removal in wastewater treatment applications, contributing to the development of sustainable remediation technologies. Granite powder achieved 43.5% dye removal at pH 11, 600 mg/L dose, and 80 min. Eggshell powder removed 95% at pH 3, 600 mg/L dose, and 80 min. Hematite powder was most effective, removing 97.6% at pH 7, 600 mg/L dose, and 80 min. Hematite powder exhibits strong adsorbate affinity, favourable adsorption, and fast kinetics. Eggshell powder has a high adsorption capacity, while granite powder shows a high predicted equilibrium capacity. Adsorption follows monolayer formation (Langmuir isotherm) and pseudo-second-order kinetics, indicating chemisorption. These adsorbents are cost-efficient and easy to handle. Hematite powder is a novel adsorbent for C.I. Basic Yellow 40 removal from wastewater.