Response Surface Methodology-Driven Optimization of Flocculation-Assisted Wastewater Remediation Using Tamarind Seeds

ABSTRACT Freshwater scarcity, representing barely 1% of the global water reserve, constitutes a critical challenge to human health, environmental sustainability, and socio-economic development. Currently, nearly 40% of the world’s population resides in arid and semi-arid regions, a figure projected to exceed two-thirds by 2025. Concurrently, rapid industrialization, escalating pollution loads, and progressive environmental degradation have intensified pressure on limited water resources. In this context, the exploration of sustainable and naturally derived treatment materials has gained substantial importance. The present investigation focuses on the application of a naturally occurring bio-mineral adsorbent derived from tamarind seeds for wastewater remediation. Response Surface Methodology (RSM), a robust statistical and mathematical optimization tool, was employed to model and evaluate the interactive effects of critical operational parameters influencing pollutant removal efficiency. Owing to their high surface area, porous structure, and abundant functional groups, tamarind seed-based natural adsorbents exhibit significant potential for contaminant adsorption. Flocculation-assisted treatment experiments were conducted using tamarind seed dosages ranging from 0.1 to 1.0 g/L under varying pH and contact time conditions. Optimal removal efficiencies were achieved at pH 6.25 with a dosage of 0.1 g/L, yielding 74% turbidity reduction; at pH 6.5 with 0.6 g/L dosage, resulting in 41% Chemical Oxygen Demand (COD) removal; and at pH 6.5 with 1.1 g/L dosage, achieving 76% Total Solids (TS) reduction over an optimized contact time of 46.4 minutes. These findings demonstrate that tamarind seed-based bio-adsorbents provide an efficient, low-cost, and eco-friendly alternative for wastewater treatment. The utilization of such organic materials presents a viable strategy for enhancing water quality, enabling safe water reuse, and mitigating associated public health risks while promoting sustainable environmental management. Keywords: Tamarind seed, turbidity, bio-coagulant, coagulation-flocculation, response surface methodology.