木质素磺酸钠对1060工业纯铝在盐酸介质中的缓蚀性能  

Inhibitive action of sodium lignosulfonate on 1060 industrial pure aluminum in hydrochloric acid media

作　　者：陈永强 雷然 李向红 CHEN Yong-qiang;LEI Ran;LI Xiang-hong(College of Chemical Engineering,Southwest Forestry University,Kunming 650224,China)

机构地区：[1]西南林业大学化学工程学院,云南昆明650224

出　　处：《应用化工》2022年第2期360-366,372,共8页Applied Chemical Industry

基　　金：国家自然科学基金项目(51761036);云南省基础研究计划杰出青年项目(202001AV070008);云南省万人计划“青年拔尖人才”专项(51900109)。

摘　　要：采用失重法、动电位极化曲线、电化学阻抗谱(EIS)、扫描电子显微镜(SEM)和原子力显微镜(AFM)系统研究了阴离子表面活性剂木质素磺酸钠(SLS)对1060工业纯铝在盐酸中的缓蚀作用。结果表明,SLS对铝在HCl中的腐蚀产生显著抑制作用,并且缓蚀率随SLS浓度的增加而升高。25℃时,1.0 g/L SLS的最高缓蚀率可达83.0%,温度升高后抑制腐蚀作用有所降低。SLS在铝表面的吸附行为服从Langmuir吸附等温方程,标准吸附Gibbs自由能(ΔG_(ads))绝对值在20~28 kJ/mol范围内,表明吸附作用方式为包含物理作用和化学作用的混合型吸附。极化曲线表明SLS为阴极型缓蚀剂。Nyquist图谱在高频区呈现弥散容抗弧,在低频区域呈现大段感抗弧,添加少量SLS后铝腐蚀的电荷转移电阻增大,且电化学腐蚀过程由两个时间常数控制。SEM和AFM表明SLS有效抑制了铝表面在HCl溶液中的腐蚀,均方根粗糙度(R_(q))降低了277 nm。The inhibitive action of anionic surfactant of sodium lignosulfonate(SLS)on 1060 industrial pure aluminum in hydrochloric acid media was studied by weight loss,potential dynamic polarization curves,electrochemical impedance spectroscopy(EIS),scanning electron microscope(SEM)and atomic force microscope(AFM).These results show that SLS exhibits a significant inhibitory effect on the corrosion of aluminum,and the inhibition efficiency increases with the increase of SLS concentration.At 25℃,the maximum inhibition efficiency of 1.0 g/L SLS can reach as high as 83.0%.The inhibition is dropped to more extent with the increase of temperature.The adsorption behavior of SLS on aluminum surface follows Langmuir adsorption isotherm,and the absolute value of the standard adsorption Gibbs free energy(ΔG _(ads))is in the range of 20~28 kJ/mol,which indicates that the adsorption type of SLS on aluminum surface involves the mixed adsorption comprising physical and chemical effects at the same time.The potentiodynamic polarization curves show that SLS is a cathodic inhibitor that mainly suppresses the cathode.Nyquist diagram shows dispersive capacitive reactance arc at the high frequency region and inductive arc in the low frequency region.The charge transfer resistance of aluminum increases after adding a small amount of SLS.There are two time constants that control the electrochemical corrosion process.SEM and AFM showed that SLS efficiently retarded the corrosion of aluminum surface in HCl solution,and the root mean square roughness(R _(q))was reduced by 277 nm.

关 键 词：木质素磺酸钠 铝 盐酸 缓蚀 吸附 

分 类 号：TQ047.6[化学工程] TQ133.3