The SEM analysis was used to study the morphology of the sludge collected at different intervals to determine the optimum time in which all metals have been oxidized and coprecipitated. The EDS connected to SEM assisted to determine the presence and quantity of metals (percentage) in the sludge produced between 5 and 30 minutes. show the images of sludge that was studied through the SEM-EDS. This confirms the densification indicated by the FT-IR spectrum where low transmittances (high absorptions) were observed after 15 minutes. Sedimentation or densification might increase as time increases. The iron, oxygen and sodium showed dominance in all sludge produced confirming the precipitation of ferric hydroxide, breakdown of sodium ferrate and presence of sodium hydroxide. It can also be seen in Figure .12 that the amount of iron decreased with time due to densification of the sludge through precipitation of alkali and alkaline earth metals including Na and Mg, and other heavy metals such as Zn and Mn which could block its detection by the instrument.