Synthesis And Properties Study Of Imidazoline Corrosion Inhibitor Used In Oilfield Reinjection Water

Reinjection water development is used widely in Chinese oilfield.Usually reinjection water is sewage spearated from oilfield produced liquid. It contains multiple ingredient such as H₂S, CO₂, O₂ and other corrosion medium, which result in metal corrosion of equipment and pipeline. The phenomenon affected usual oilfield production. An effective way to inhibit metal corrosion is using corrosion inhibitor used in oilfield reinjection water. In this paper, the synthesis of imidazolines and their derivatives was researched in order to apply them in oilfield reinjection water production system according to practical demand in oilfield production.Firstly, the kind of imidazoline compound was synthesized by the method of solvent-dewatering. Secondly, nitrogen-containing heterocyclic ring was connected with a hydrophilic group in the structure of imidazoline compound, which turn into imidazoline quaternary and enforce water-solubility of the imidazoline compound.The characteristic structures of imidazoline compound and its derivatives were indentified by way of infrared absorption spectrum.The corrosion inhibition effects of imidazoline corrosion inhibitor were evaluated in different experimental conditions by means of weight loss and polarization technique. According to the experimental results of weight loss and polarization technique, the inhibition mechanisms were adsorption mechanism and the mechanism of inhibition of acid corrosion.In order to apply the corrosion inhibitor in oilfield production,the corrosion inhibition effects of imidazoline corrosion inhibitor used for A3 steel were tested in different conditions such as temperature, H₂S concentration, CO₂ concentration, O₂, stable and dynamic condition.