Amidst the increasing problems of water scarcity and textile pollution, the wastewater treatment industry is in dire need of affordable adsorbents. The textile industry needs to find cost-effective ways to mitigate its environmental impact, as it is a major cause of water pollution. Since water stress is increasing globally, affordable adsorbents are crucial for providing sustainable and approachable solutions to pollution problems, guaranteeing efficient water treatment, and encouraging environmental preservation in the face of growing concerns. The purpose of this study is to determine how well waste basalt quarry dust (BQD) works as an adsorbent to remove malachite green (MG) dye, a cationic dye that is a major source of dye pollution. The characterization of BQD reveals a zeta potential of -23.3 mV, which is a promising indication of MG adsorption. According to BET analysis, the surface area of BQD is 8.731 m2/g, the pore volume is 0.015 cc/g, and the pore width is 3.794 nm. Various kinetic and equilibrium models are used to investigate the adsorption process. The adsorption kinetics show a well-fitted pseudo-first-order non-linear model with an adjusted R2 value of 0.99415. This shows how effective and reliable the BQD is an adsorbent. The Sips isotherm is an excellent fit with an adjusted R2 value of 0.9827, demonstrating the robustness of the adsorption process. Thermodynamic studies emphasize the spontaneity and exothermic nature of the adsorption process. In addition to these, the response surface methodology is used for optimising the removal efficiency, and the quadratic model of the central composite design is well-fitted to the adsorption process, exhibiting a predicted R2 value of 0.9917, which is greater than that of the artificial neural network model (R2 = 0.9698). Desorption studies also demonstrate the remarkable resilience of the adsorbent, maintaining 85% of its effectiveness after five cycles using 0.5 M HCl as an eluent. This study highlights the potential for long-term sustainable reuse of BQD, supporting the circular economy by advancing the development of affordable adsorption processes that are environmentally friendly, and utilizing byproducts from one industry as resources to treat waste from another.
