Nano-Silicate from Paddy Waste as Natural Corrosion Inhibitor

The highly advance usage of an agricultural waste of rice husk ash (RHA) from Oryza sativa L. was developed by extracting the nanosilicate contained in RHA as a corrosion inhibitor for carbon steel in 0.5 M NaCl media. The corrosion measurement was studied using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), surface analysis, and adsorption isotherm study. The extracted nanosilicate powder from RHA was analyzed using Fourier Transform Infrared Spectroscopy (FTIR) to identify the presence of functional groups (SiO2), whereas X-ray diffraction (XRD) to identify the phase of silica from RHA. The particle size of nanosilicate was confirmed by transmission electron microscopy (TEM) and Zetasizer analysis, and the results show particle size of nanosilicate in the range of 5–10 nm. The maximum inhibition efficiency (IE%) is up to 88% in NaCl media. On the other hand, the inhibitor adsorption properties follow Temkin isotherm with mixed type of inhibition properties. Surface analysis on specimen that was treated with nanosilicate was smoother with fewer pits and pores than untreated specimen. In future perspectives, nanosilicate from RHA has a promising advantages and imminent applications for industries revolving with composites, biomedicine, and many more

Anticorrosive properties of nano silicate from paddy husk in salt medium

Anticorrosive properties of nano silicate from paddy husk in salt medium was investigated via weight loss method, Tafel polarization and impedance techniques. Prior to the corrosion test, the silica powder was obtained from burning the rice husk and extended with a chemical treatment process. The size of silica powder was characterized via zeta sizer and showed the amount of micro silica particle appear more than the nano size particle. Nano silica powder was produced from the refluxing process of micro silica to enhance the good properties of silica particle. The corrosion inhibition efficiency of nano silicate showed good inhibition with increased in inhibitor concentrations. Weight loss test exhibits high inhibition as more than 80% even, immersed in the corrosive medium until 14 days. The nano silicate inhibitor affected the anodic reaction as showed by Tafel plot analysis. Impedance results also correlated with other test as shown by the large size of Nyquist semicircle which represents as high resistance of charge transfer. The surface morphology of inhibited specimen showed a smooth surface after nano silicate inhibitor applied in the NaCl medium as observed through scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX)