Role of TiO2 nanomaterial in the treatment of polluted Cauvery River water in Tiruchirappalli district, Tamil Nadu, India

This study evaluates the water quality of the Cauvery River in Tiruchirappalli District, Tamil Nadu, India using advanced statistical analysis and nanotechnology-based remediation. Water samples were collected from 20 monitoring stations during the pre-monsoon period of 2021 and analyzed for key parameters, including pH (7.2–8.9), electrical conductivity (1301–2833 µS/cm), total dissolved solids (1063–2116 mg/L), biological oxygen demand (16–24 mg/L), and chemical oxygen demand (18–33 mg/L). Several stations recorded BOD and COD values exceeding the permissible limits of 3 mg/L and 10 mg/L, respectively, indicating severe pollution from agricultural runoff and industrial discharge. Principal component analysis (PCA) and factor analysis (FA) are identified nitrates, phosphates, and dissolved solids as major contaminants. TiO₂ nanoparticles were applied for photocatalytic remediation, resulting in significant reductions in EC (32%), TDS (40%), BOD (60%), and COD (55%), alongside a 45% increase in dissolved oxygen (DO). This novel integration of nanotechnology and statistical analysis offers a sustainable and effective solution for enhancing freshwater quality and guiding future pollution management strategies.