一种高效酸化缓蚀剂的合成及评价

Synthesis and evaluation of high-efficiency acidizing inhibitor

根据曼尼希(Mannich)反应机理选用苯乙酮、甲醛、乙二胺为原料合成了一种适用于盐酸介质的高效酸化缓蚀剂,通过对反应物的摩尔比、反应时间、反应温度、pH值等进行实验分析,评价了产物的缓蚀性能。确定最有利的反应条件为:苯乙酮、甲醛、乙二胺摩尔比2∶2∶1,pH值2～3,反应温度80℃,反应时间8 h。合成出的缓蚀剂与铁原子(离子)形成稳定的环状络合物吸附在金属表面,通过覆盖效应起到缓蚀作用。80℃条件下,质量分数为1.0%的缓蚀剂在15%盐酸溶液中对N-80钢片的腐蚀速率仅为1.936 8 g·m-2·h-1,达到SY/T 5405—1996标准中的一级标准,是一种溶解分散性良好、用量少、缓蚀效率高的酸化缓蚀剂。

Based on the Mannich reaction mechanism, a high-efficiency acidizing inhibitor which is suitable for the hydrochloric acid medium is synthetised through choosing acetophenone, formaldehyde and ethylene diamine as material in this paper. By analyzing the mole ratio, reaction time, reaction temperature and the pH value of reactant, the corrosion retarding performance of the product is evaluated. The optimum reaction conditions are defined, namely the mole ratio of acetophenone, formaldehyde and ethylene diamine is 2：2：1, with pH value 2-3, reaction temperature 80℃, reaction time 8 h. The stable circular complex compound, formed by the corrosion inhibitor and ferrum atom, is adsorbed on the surface of the metal, which plays a corrosion inhibition with coating effect. The corrosion rate of 1.0% inhibitor against N-80 steel plate is 1.936,8 g per square meter and per hour in HCL solution at 80℃, which reaches the primary standard of SY/T 5405 -1996 evaluation criterion. It is an acidizing inhibitor with good dissolving and dispersing capacity, low use concentration and high corrosion mitigation effectiveness. Corrosion mitigation effect is able to satisfy the demand of carbonate acidizing.