Corrosion of copper alloys (copper, bronze and brass) in soil was evaluated at ambient temperature using various methods such as electrochemical impedance spectroscopy (EIS), polarization curves and Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectroscopy microanalysis measurements. Three equivalent circuits were separately used to interpret the obtained impedance spectra. The EIS measurements indicated that the polarization resistance of all electrodes increases with increasing the immersion time. SEM showed a presence of three layers of corrosion products with various composition and morphology covering each electrode. In addition, it was found that at 20% of moisture content the Rp values and the current density of all electrodes in the studied soil give the following order: copper > bronze > brass. Good consistency between the data obtained from EIS and PP measurements was observed.

In this study, Natural Calcium Carbonate (NCC) that was characterised by X-ray diffraction has been used as an adsorbent in the removal of Zn2+, from aqueous solution by a batch adsorption technique. The effects of various experimental parameters such as solution PH, initial concentration of solution, contact time, adsorbent masses and stirring speed were investigated. The results showed that basic PH and the average stirring speed were favourable for the adsorption of Zn2+, and the adequate equilibrium time for the adsorption of Zn2+ onto Natural Calcium Carbonate was 80min. The experimental data were analysed by the linear form of Langmuir, Freundlich. Isotherm models and showed a good fit with the Langmuir isotherm model. Adsorption kinetic was studied using pseudo first order kinetic equation, second order kinetic equation. The adsorption kinetic followed the pseudo second order equation.