PMEPT在10%HCl中对A_3钢的缓蚀作用及吸附热力学研究  

The Adsorption Thermodynamics and Inhibition of PMEPT on A_3 steel in 10% HCl

作　　者：阴文敏[1] 蒋晓慧[1] 樊光银[1] 涂胜[1] 王后臣[1] 李金博[1] 

机构地区：[1]西华师范大学化学化工学院,四川南充637009

出　　处：《西华师范大学学报（自然科学版）》2010年第2期216-220,共5页Journal of China West Normal University(Natural Sciences)

基　　金：四川省教育厅重大培育项目(07ZZ037);四川省化学应用与污染控制技术重点实验室开放基金(10scpc-2)

摘　　要：以乙酰乙酸乙酯,硫脲,3-吡啶甲醛为原料,苯甲酸为催化剂在无溶剂条件下"一锅法"制备了4-(3-吡啶基)-6-甲基-5-乙氧羰基嘧啶-2-硫酮(代号:PMEPT),产率达83%,并用1HNMR表征了其结构。采用失重法评价了该化合物在10%HCl中对A3钢的缓蚀作用,结果表明,该化合物对A3钢在酸性环境中的腐蚀具有良好的抑制作用,缓蚀率随PMEPT浓度的增加而增加,在其浓度为5mmol/L时,缓蚀率达92%;缓蚀率随温度升高而降低,说明该化合物是吸附型缓蚀剂,低温时在A3钢表面的吸附符合Langmuir吸附等温式。数据处理表明吸附过程是自发进行的(ΔG0<0,ΔH0<0)。4 - （3 - pyridyl） ） - 6 - methyl - 5 - ethoxycarbonylpyrimidin - 2 - thione （ designated PMEPT） was prepared by ＂one-pot＂ method with acetyl ethyl acetate, thiourea and 3 - pyridine formaldehyde as raw materi- als, and benzoic acid as a catalyst. The structures were characterized by 1HNMR and the yield was about 83%. Inhibitive efficiency of PMEPT on A3 steel in 10% HCI was investigated by weight loss method. The results showed that PMEPT inhibited the corrosion of A3 steel in acidic medium. The inhibition efficiency increased with the concentration of the inhibitor, and it was 92% at 5mmol/L of PMEPT. The inhibition efficiency decreased with tem- perature in the test, suggesting that PMEPT is an adsorptive inhibitor. The adsorption of PMEPT on the steel surface in the acid solution was found to obey Langmuir＇ s adsorption isotherm at 30℃. The analysis of the data indicated a spontaneous adsorption of inhibitor on the surface of A3 steel（△G 〈0,△H0 〈0）.

关 键 词：BIGINELLI反应 Langmuir等温吸附 缓蚀性能 

分 类 号：O621.24[理学—有机化学]