Adsorption of benzotriazole on mercury from different base electrolytes

224-226Electrocapillary curves for 1M solutions of NaCl, NaNO3 and Na2SO4 in the presence of different concentrations of benzotriazole show that the organic compound adsorbs both on positively and negatively charged metal surfaces. The extent of adsorption from these base electrolytes follows the order Na2SO4 > NaNO3 > NaCl. Thermodynamic parameters like charge on the metal surface (qM), the surface excess of organic molecule adsorbed (org), surface coverage (q) and free energy of adsorption (- G) are evaluated and presented. The adsorption of benzotriazole on mercury obeys Langmuir’s adsorption isotherm in all the cases, irrespective of the nature of the base electrolyte used

The adsorption of thiosemicarbazide at the mercury/phosphoric acid solution interface

959-963Adsorption of thiosemicarbazide on the mercury electrode from 0.2 N phosphoric acid has been studied using a capillary electrometer. Electrocapillary curves have been obtained in the presence of different concentrations of the adsorbate. Thermodynamic parameters like charge on the metal surface (qM) and surface excess of organic molecules adsorbed (Gorg) have been calculated. From the adsorption data, it is clearly seen that the adsorption of this compound obeys Temkin's adsorption isotherm. The variation of free energy of adsorption with charge on the metal surface has been explained

Synergistic influence of iodide ions on the inhibition of corrosion of mild steel in sulphuric acid by cyclohexylamine

167-171The synergistic inhibition of corrosion of mild steel in 0.5 M H2SO4 by a combination of cyclohexylamint (CHA) and iodide ions has been studied using different electrochemical techniques. Corrosion inhibition is found to decrease with increase in the concentration of CHA. Iodide ions are found to enhance the inhibition by CHA considerably. Synergistic parameters such as S1, and Sθ obtained from values of inhibition efficiency and surface coverage are found to be more than unity. This observation clearly shows the synergistic influence of iodide ions on the corrosion inhibition by CRA. The adsorption of CHA alone and in combination with iodide ions obeys Langmuir's adsorption isotherm.</span

Influence of anions on corrosion inhibition and hydrogen permeation through mild steel in acidic solutions in the presence of <i>p</i>-tolyl thiourea

68-73The influence of anions such as chloride and sulphate on the inhibition of corrosion of mild steel by p-tolyl thiourea (PTTU) in 1N HCl and 1N H2SO4 has been studied using weight loss and gasometric measurements, Galvanostatic polarisation studies and ac impedance measurements. The compound is found to be less inhibitive in 1N HCl than in 1 N H2SO4. The influence of p-tolyl thiourea on the extent of hydrogen permeated through mild steel in acidic solutions has been studied using electro-permeation technique. The compound is found to enhance the permeation of hydrogen through mild steel in both the acids. The adsorption of p-tolyl thiourea on the mild steel surface from both the acids obeys Temkin's adsorption isotherm. The increase of charge transfer resistance (Rt) and decrease in double layer capacitance (Cd1) values of the metal electrode in the presence of the test compound (PTTU) show the adsorption of the compound on the metal surface

Influence of anions on the performance of anisidines as inhibitors for the corrosion of mild steel in acidic solutions

168-174<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:arial;mso-ansi-language:en-us;mso-fareast-language:="" en-us;mso-bidi-language:ar-sa"="">The influence of anisidines on the corrosion of mild steel in 1N HCI and 1N H2SO4 has been investigated by weight loss, gasometric and some other electrochemical techniques. Anisidines are found to be inhibitive in 1N HCI. In 1N H2SO4, o–anisidine inhibits the corrosion at all concentrations whereas m –anisidine inhibits at concentrations more than 20 mM. However, p–anisidine accelerates the corrosion at all concentrations. They behave predominantly as cathodic inhibitors in 1N HCI and inhibit the corrosion in 1N H2SO4.These bring down the permeation of hydrogen through mild steel in 1N HCI and enhance it in 1N H2SO4,The adsorption of anisidines on the metal surface is found to obey Langmuir's adsorption isotherm.</span

Adsorption of Naphthalene at Mercury/Aqueous Solution Interface

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