Inhibition effect of some aniline compounds on corrosion of mild steel in 3% HF

Abstract

246-250<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:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">The corrosion inhibition efficiencies(IE%) of aniline(AL), p-<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;mso-bidi-font-style:="" italic"="">toluidine(PTD), <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:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">p-anisidine (PAD), p-<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:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">phenitidine ( PPD) and N,N-dimethyl aniline(DMA) have been evaluated in 3% HF by weight loss and potentiostatic polarization methods. PAD is the best inhibitor and IE% can be classified in the following order: PAD> PPD > PTD > DMA > AL. The effect of temperature (range 303-333 K) on the corrosion behaviour of mild steel in plain HF solution and inhibited acid was also studied. The corrosion rate increased with increasing temperature both in uninhibited and inhibited acid and the values of IE% of all the inhibitors depend on temperature. The inhibitors act as mixed adsorption type inhibitors. Adsorption of AL, DMA and PTD on mild steel in 3% HF interface corresponds to Langmuir adsorption isotherm model while PAD and PPD appear to adsorb on the metal surface according to Temkin adsorption isotherm.</span