Industrial Water Treatment ›› 2026, Vol. 46 ›› Issue (1): 81-88. doi: 10.19965/j.cnki.iwt.2025-0125

• RESEARCH AND EXPERIMENT • Previous Articles     Next Articles

Corrosion inhibition performance and mechanism of a novel phosphorus-free corrosion inhibitor CD/PASP on carbon steel in phosphoric acid

Chunjie SHI1(), Xinhua LIU1,2(), Baojing LUO1, Yuan ZHANG1, Junxia GUAN1, Ying WANG1, Hongxia ZHANG1, Hongli ZHAO1, Xiaodan LIU1, Xinyuan ZHANG1, Yubo XIA1, Xujia SHI1, Yizhao GAO1   

  1. 1. Department of Chemistry, Tangshan Normal University, Tangshan 063000, China
    2. Tangshan Key Laboratory of Green Specialty Chemicals, Tangshan 063000, China
  • Received:2025-04-18 Online:2026-01-20 Published:2026-02-03
  • Contact: Xinhua LIU

新型无磷缓蚀剂CD/PASP对碳钢在磷酸中的缓蚀性能与机理

石春杰1(), 柳鑫华1,2(), 罗宝晶1, 张源1, 关俊霞1, 王瀛1, 张红霞1, 赵红丽1, 刘晓丹1, 张心媛1, 夏雨博1, 史旭佳1, 高一钊1   

  1. 1. 唐山师范学院化学系,河北 唐山 063000
    2. 唐山市绿色专用化学品重点实验室,河北 唐山 063000
  • 通讯作者: 柳鑫华
  • 作者简介:

    石春杰(1989— ),硕士,实验师,E-mail:

  • 基金资助:
    河北省自然科学基金项目(D2022105004); 唐山师范学院科研学科建设项目(20265128054); 唐山师范学院科研学科建设项目(20266128054); 河北省高等学校科学技术研究项目(ZC2022081)

Abstract:

A novel polyaspartic acid derivative (CD/PASP) was synthesized, and used as a green, efficient, and economical corrosion inhibitor to inhibit the corrosion behavior of Q235 low carbon steel in 0.5 mol/L phosphoric acid solution. The structure of CD/PASP was verified by infrared spectroscopy (FTIR) and nuclear magnetic hydrogen spectroscopy (1H NMR), and thermogravimetric analysis showed its excellent thermal stability within 200 ℃. The weightlessness experiment showed that when the dosage of CD/PASP was 80 mg/L, it had an inhibitory effect on the corrosion of Q235 steel, with a corrosion inhibition rate (η) of up to 85.19%. The adsorption of CD/PASP on the surface of Q235 steel conformed to Langmuir adsorption isotherm model, and the adsorption free energy (ΔG a d s 0≈-38.92 kJ/mol) indicated that its adsorption was a spontaneous process, involving both physical and chemical adsorption mechanisms. Polarization curves and electrochemical impedance spectroscopy indicated that CD/PASP was a hybrid corrosion inhibitor that could form a protective film on the metal surface to effectively block the corrosion process. Surface analysis (SEM, AFM, XPS, etc.) further revealed that CD/PASP formed N—Fe chemical bonds with the steel substrate through nitrogen heteroatoms in the molecule, forming a hydrophobic protective layer on the metal surface that effectively blocked corrosive media and suppressed charge transfer processes. The synthesized CD/PASP was an efficient steel corrosion inhibitor with great potential for application in the field of industrial metal corrosion prevention.

Key words: corrosion inhibitor, Q235 steel, weightlessness, electrochemistry, surface analysis

摘要:

合成了一种新型聚天冬氨酸衍生物(CD/PASP),并将其作为绿色、高效、经济的缓蚀剂,用于抑制Q235低碳钢在0.5 mol/L磷酸溶液中的腐蚀行为。通过红外光谱(FTIR)和核磁氢谱(1H NMR)验证了CD/PASP的结构,热重分析表明其在200 ℃以内具备良好的热稳定性。失重实验显示,当CD/PASP添加量为80 mg/L时,其对Q235钢的腐蚀具有抑制作用,缓蚀率(η)可达85.19%。CD/PASP在Q235钢表面的吸附符合Langmuir吸附等温模型,吸附自由能(ΔG a d s 0≈-38.92 kJ/mol)表明其吸附为自发过程,并同时包含物理与化学吸附机制。极化曲线和电化学阻抗谱表明,CD/PASP是一种混合型缓蚀剂,能在金属表面形成一层保护膜,有效阻滞腐蚀过程。表面分析(SEM、AFM、XPS等)进一步揭示,CD/PASP通过分子中的氮杂原子与钢基体形成N—Fe化学键,在金属表面形成疏水保护层,有效阻隔腐蚀介质并抑制电荷转移过程。CD/PASP是一种高效钢铁缓蚀剂,在工业金属防腐领域具有很大应用潜力。

关键词: 缓蚀剂, Q235钢, 失重法, 电化学法, 表面分析

CLC Number: