氨基磺酸溶液中烷基咪唑啉与碘化钾复配对碳钢的缓蚀作用

Corrosion Inhibition of Alkyl Imidazoline in Association With KI on Carbon Steel in Amidosulphuric Acid Solution

采用失重法、电化学方法研究了2-十一烷基-N-羧甲基-N-羟乙基咪唑啉(UHCI)和KI的复配在8%氨基磺酸溶液中对碳钢的缓蚀协同作用。结果表明,复配缓蚀剂可有效抑制45#碳钢在氨基磺酸溶液中的腐蚀,当缓蚀剂总浓度为0.4%时,UHCI和KI浓度之比为9:1时缓蚀效果最好。交流阻抗数据显示碳钢电极从空白时的1个时间常数转变为有缓蚀剂时的2个时间常数,极化曲线表明该复配缓蚀剂为混合型缓蚀剂。该缓蚀剂的吸附行为符合Langmuir吸附等温式,吸附机制为化学吸附。

The mixture of 2-undecyl-N-carboxymethyl- N-hydroxyethyl imidazoline （UHCI） to KI as a corrosion inhibitor for carbon steel in 8 % amidosulphuric acid solution was investigated by weight loss test, electrochemical methods. Results show that the combined inhibitor strongly inhibits the corrosion of 45# carbon steel in amidosulphuric acid solution and the mixture with the mass ratio （UHCI：K1） of 9：1 has the best corrosion inhibition at a total concentration of 0.4 %. The impedance spectra of carbon steel electrodes change from one time constant into two time constants when the mixture inhibitor adds into the blank solution while the polarization curves indicate that the mixture behaves as a mixed type inhibitor. The absorption of the mixture is found to follow the Langmuir adsorption isotherm and the mechanism is chemisorption.