CORROSION INHIBITION

Corrosion Inhibition Of Aluminum In Hydrochloric Acid Solution By Alkylimidazolium Ionic Liquids



Ionic Liquids in Corrosion Inhibition

Introduction

Aluminium Resistance against prior termcorrosionnext in water may be due to the rapidly formed a compact, strongly Adherent and continuous oxide film. This way of aluminium and its alloys are widely used in many industries, such as reaction vessels, pipe, machinery and chemical batteries. Hydrochloric acid solution used for etching, chemical and electrochemical etching aluminium. However, the presence of aggressive chloride ions are present a localized attacks (Burleigh, 1992, 2799). Various mechanisms have been proposed to explain the breakdown of the oxide film. One of them takes into account the chloride ions adsorption on the surface oxide chloride ion penetration through film, aluminium oxide and localized dissolution of metal oxides in interface in a row one electron transfer reactions. Recently he showed that the chloride oxide film has entered, but that it was a chemisorbed on a surface oxides and acts as a partner in the reaction, aiding disbanding through the formation of which - chloride complexes (Errata, 1994, 911).

From general aggressive acids inhibitors are typically used to reduce corrosion attack on metallic materials. The preceding inhibitionnext termcorrosion aluminium in acid medium reported recently using hydrazone, anionic surfactants and amino acids as inhibitors. Most effective organic inhibitors used contain heteroatoms e.g., N, s, and a few bond within their molecules through which they are adsorbed on metal surfaces. Usually localized prior termcorrosionnext can be prevented by adsorptivn inhibitors prevent the adsorption of aggressive or by creating more anions resistant oxide film on the metal surface (Errata, 1994, 910).

Thus, it was considered appropriate to examine three synthetic corrosion behavior of inhibition of imidazolium ionic liquids (table 1) aluminium in hydrochloric acid. There are almost the same chemical structure and carbon chain length differences between n-alkyl imidazolium rings of these compounds.

Table 1.

Name, structure and molecular weights of alkylimidazolium ionic liquids used.

Name and abbreviation

Molecular structure

Relative mol. weight

1-Butyl-3-methylimidazolium chlorides (BMIC)

174.67

1-Hexyl-3-methylimidazolium chlorides (HMIC)

202.67

1-Octyl-3-methylimidazolium chlorides (OMIC)

230.67

Experimental

Use previous termcorrosionnext term inhibitors chlorides 1 butyl-3-methylimidazolium, 4-hexyl-3-methylimidazolium chloride and 1-Octyl-3-methylimidazolium chloride Laboratory synthesis and specific synthetic methods were similar to those previously described. Synthetic products characterized by NMR (Bruker Avance DPX-300) and infrared (Bio-Rad FTS-40, the sample is divided between the KBr plate) and the spectral characteristics were described as follows. Overall structure of the inhibitors are shown in table 1.

1-Butyl-3-methylimidazolium chlorides—BMIC

The H NMR spectrum for BMIC (300 MHz; CDCl3; Me4Si) ...