Turbid-Metric Approach on the Study of Adsorptive Component of Paint Effluent Coagulation Using Snail Shell Extract

This work focuses on the adsorptive study of paint effluent coagulation using snail shell coagulant (SSC), in which samples were subjected to physiochemical and instrumental analyses [Fourier transform infrared (FTIR), differential scanning calorimetry/thermo gravimetric analysis (DSC/TGA), scanning electron micrograph (SEM), X-ray diffraction (XRD)]. Nephelometric jar test was also employed and the data generated were subjected to adsorptive kinetic, equilibrium and thermodynamics analyses. 42 % protein was recorded for the snail shell. SEM images and FTIR spectra indicated significant porosity and ammine presence in the SSC. DSC/TGA and XRD indicated samples of high thermal stability and organized crystalline structure, respectively. The data correlated best with Langmuir isotherm with linear regression coefficient (R2) values >0.9 over the temperatures investigated. Pseudo-second-order kinetic model best described the process at K2< 0.05 (g/mg/min) and R2 values >0.99. The thermodynamics parameter (Δ G, Δ H and Δ S) shows that the process was feasible and spontaneous. The intra-particle diffusion was found to be the rate-limiting step. It could be concluded that while SSC achieved 92 % turbidity removal, the adsorptive component of the process was significant.