This work investigates the effect of some essential plating variable of zinc electro-deposition on low carbon steel substrates. The variation of plating parameter, the depth of immersion, distance between the anode and the cathode on voltage, plating time and coating thickness was considered. The steel substrates were immersed into solution of zinc electroplating bath for varying voltage between 0.5 and 1.0 V. It was discovered that the sample plated at 0.8 V for 20 min gave the best plating properties and it was also observed that increase in applied voltage, plating time, depth of immersion and decrease in distance of the object (cathode) from the anode increases weight gained. Microstructural studies with SEM/OPM however, revealed fine grained deposit of the deposited zinc and the inclusion of addition agent.

A photochemical investigation and synergetic blend for wastewater purification was carried out. Blends of different peels: Potato-, Apple and Pineapples-peals (PAP-peals) were impregnated with aqueous solutions of ZnCl 2 following the variant of the incipient wetness method for activation of activated carbon (AC). Different concentrations were used to produce impregnation ratios. Activation was carried out in a tube furnace by heating to 700 with 1 hour soaking time. Scanning Electron Microscopic with attached energy dispersive spectrometer (SEM/EDS), Atomic Adsorption Spectrometry (AAS) and Fourier Transform Infrared spectrometer (FTIS) equipments were used for the characterization of the AC produced. The result shows that PAP-peals derived activated carbons had micro porous characteristics. The study revealed that these new combined adsorbents materials are inexpensive, easily available and they have applications for the removal of Cu, Pb and Cr contained in industrial effluents.

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Enhancement of engineering materials is essential for averting service failure and corrosion attack in the industries. The impact of Ni as inoculant and solidification process on the corrosion resistance of an Al-Mg-Si alloy has been investigated in 3.65% NaCl solution using potentiodynamic polarization measurement. The alloying compositions and phase change were determined with energy dispersive spectroscopy (EDX) and x-ray diffraction (XRD). The surface morphology of the alloyed sample using scanning electron microscope (SEM) showed that Ni particles were well dispatched along the interface. The addition of Ni to Al-Mg-Si alloy led to the precipitation and crystallization of Al2Ni and AlNi2 formed at the grain boundaries. Equally, as the percentage of Ni content increases in the alloy, the corrosion rate decreased due to the presence of Al2Ni3 which proceeded at active regions. Inoculation of Ni particles coupled with increase in solidification reduces the possibility of corrosion penetration within the structural interface.

Susceptibility of mild steel to corrosion attack has restricted its industrial applications, despite its numerous advantageous characteristics. Comparison of the inhibitive tendency of a mixture of zinc gluconate (ZG) and ferrous gluconate (FG) on the corrosion behavior of mild steel in acid and saline media was investigated using electrochemical and weight loss techniques. The FG:ZG ratio was dosed from 0.5:0.5 to 2.0:2.0 g/v at an interval of 0.5:0.5. The surface morphology of the corroded mild steel samples was evaluated by high resolution scanning electron microscope equipped with energy dispersive spectroscopy (HR-SEM/EDS). Experimental results indicated that the combined inhibitor significantly reduced the corrosion rates of mild steel, with the maximum inhibition efficiency (IE) of 100% and 48% at 28 ºC in the presence of 1.5:1.5 g/v concentrations in 3.5 % NaCl and 0.5 M H2SO4 solutions, respectively. The SEM micrographs of the inhibited samples show a clearly reduced surface degradation as opposed to the surface morphology without inhibitor. Potentiodynamic polarization curves studies showed that the combined inhibitor is a mixed type inhibitor for mild steel corrosion in 3.5 % sodium chloride and 0.5 molar sulphuric acid solutions. From the set of experimental data it was found that the combined inhibitor reduced the corrosion rate through an adsorption process and obeyed Langmuir's adsorption isotherm in chloride medium and Freundlich adsorption isotherm in sulphuric acid medium at all concentrations and temperature studied. Good synergism exists between FG and ZG. The results obtained from potentiodynamic polarization are consistent with the results of the weight loss method. Synergistic performance of inhibitors was perfect in saline medium. From the analysis of grey relational grade model, the significant concentration ratios were indentified. The results showed the influence of synergistic FG:ZG at a concentration of 1.5 g/v on the corrosion rate of mild steel. Predicted results were found to be in good agreement with experimental results.