Inhibition of carbon steel corrosion in CO_(2)-saturated 3.5 wt.%NaCl solution by vanillin chitosan oligosaccharide and synergistic effect of KI additive  

作　　者：Shitao Liu Jun Zhou Guangchuan Liang Xidi Lyu Ying He Lanting Feng Hao Peng 

机构地区：[1]Petroleum Engineering School,Southwest Petroleum University,Chengdu,610500,China [2]PipeChina Southwest Pipeline Company,Chengdu,610037,China [3]Safety,Environment&Technology Supervision Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,610095,China

出　　处：《Petroleum》2024年第4期705-718,共14页油气(英文)

摘　　要：The chitosan oligosaccharide and vanillin are used as raw materials to synthesize non-toxic and water-soluble chitosan oligosaccharide derivative called vanillin chitosan oligosaccharide as a green corrosion inhibitor.The corrosion inhibition properties of 20#steel in CO_(2)-saturated solution system at 25°C and 3.5 wt%NaCl were studied.The synergistic effect of potassium iodide(KI)and VCOS on corrosion inhibition was also studied.Various techniques such as weight loss(WL),electrochemical analysis,atomic force microscopy(AFM),scanning electron microscopy(SEM),quantum chemical calculations,and molecular dynamics simulations were used to understand the inhibition properties.The inhibition efficiency of VCOS enhanced remarkably after the addition of KI,reaching an optimum value of 93.1%.EIS results showed that the inhibition of VCOS+KI on metal surface increased with time.Polarization measurements showed that VCOS and KI acted as mixed inhibitors by demonstrating anode dominance.SEM and AFM were used to study the formation of inhibition film on metal surface after 3 days immersion.We concluded that the mixed inhibitor followed Langmuir adsorption isotherm.In addition,quantum chemistry and molecular dynamics simulations were used to verify the relationship between corrosion inhibition efficiency and molecular structure.

关 键 词：Chitosan oligosaccharide derivative VANILLIN CO_(2) corrosion Carbon steel Environmental friendly inhibitors Synergistic effect Potassium iodide 

分 类 号：TE988.2[石油与天然气工程—石油机械设备] TG174.42[金属学及工艺—金属表面处理]