月桂基咪唑啉硫酸酯盐对A3钢的缓蚀性能研究

Study on Corrosion Inhibition of A Lauryl Imidazoline Sulfuric Ester to A3 Steel

以月桂酸和羟乙基乙二胺为原料、氨基磺酸为季铵化试剂,通过季铵化反应,合成了咪唑啉缓蚀剂1-羟乙基-2-月桂基-咪唑啉硫酸酯盐(LIMS),并通过失重法、极化曲线、EIS和ESEM考察了LIMS在质量分数为10%的盐酸溶液中对A3钢的缓蚀性能及表面的吸附行为。结果表明:在ρ(LIMS)=0.80 g/L时,缓蚀率为93.1%;添加ρ(LIMS)=0.05~0.80 g/L的缓蚀剂后,阳极、阴极反应作用系数fa和fc均小于1,而且两者数值相近,说明可以同时抑制阴极和阳极反应,是一种混合型缓蚀剂;LIMS分子与金属表面的吸附符合Langmuir吸附等温式,能自发吸附于金属表面,并以化学吸附为主;在50℃、腐蚀时间24 h、ρ(LIMS)=0.80 g/L时,自制缓蚀剂LIMS缓蚀率为90.6%,优于市售缓蚀剂乌洛托品(78.5%)、苯并三氮唑(82.9%)、PS-1(84.2%)、IS2129(87.3%)。

An imidazoline corrosion inhibitor,1-hydroxyethyl-2-lauryl imidazoline sulfuric ester（LIMS）was synthesized by quaternary ammonium reaction with lauric acid and N-hydroxyethyl-ethylenediamine as raw materials and amino sulfonic acid as the quaternarization reagent.Its corrosion inhibition performance and adsorption behavior to A3 steel in 10% hydrochloric acid solution were investigated by means of weight loss,polarization curve,EIS and ESEM.The results revealed that corrosion inhibition efficiency of up to 93.1% when LIMS at the mass concentration of 0.80 g/L.After adding the concentration of 0.05 - 0.80 g/L corrosion inhibitor,anode/cathode action coefficient faand fcwere lower than 1,both values were similar,LIMS could inhibit cathode and anode reaction simultaneously,was a mixed type inhibitor.The research also indicated that the adsorption of the inhibitor on A3 steel was in agreement with Langmuir adsorption isotherm and the inhibitor molecule was adsorbed into A3 steel surface spontaneously.In addition,chemisorption was the predominant mode of adsorption.The inhibition efficiency of LIMS was up to 90.6%,superior to that of urotropine（78.5%） benzotrizaole（82.9%） PS- 1（84.2%） and IS2129（87.3%） at 50 ℃ for 24 h while the mass concentration was0.80 g/L.