O,O'-(2-甲基-2,4-亚戊基)二硫代磷酸-N,N-二乙铵的合成、表征及缓蚀性能评价

合成了O,O'-(2-甲基-2,4-亚戊基)二硫代磷酸-N,N-二乙铵(PDP),用元素分析、红外光谱、核磁共振谱和X射线单晶衍射等技术手段对其结构进行了表征。PDP属四方晶系,I-4空间群,其晶胞参数为:a=2.1357(3)nm,b=2.1357(3)nm,c=0.71892(11)nm,α=β=γ=90°,V=3.2791(8)nm3,Z=8,Dc=1.156 g/cm3,F(000)=1232,μ(Mo Kα)=0.412 mm-1,F(000)=1232,S=0.952,R=0.0664,wR=0.1791[I2σ(I)]。PDP通过NH幆S和CH幆S氢键作用形成了一维超分子孔道结构。PDP在HCl溶液中对Q235钢的缓蚀性研究表明:PDP能有效抑制Q235钢的腐蚀,是阴极为主的混合型缓蚀剂,在Q235钢表面的吸附符合Langmuir吸附,属自发进行的物理化学吸附;在25℃的1.0 mol/L HCl溶液中PDP浓度为140 mg/L时的缓蚀率达到98.9%。CCDC:1404464。

Synthesis,Characterization, and Corrosion Inhibition of N,N-Diethylammonium O,O'-(2-Methyl-2,4-pentylene) dithiophosphate

A new compound, N,N-diethylammonium O,O'-(2-methyl-2,4-pentylene)dithiophosphate(PDP), was synthesized and characterized by elemental analysis, IR, NMR, and X-ray single crystal diffraction analysis. The crystallographic structure analysis reveal that PDP crystallizes in tetragonal system, I-4 space group, a=2.1357(3) nm, b=2.1357(3) nm, c=0.71892(11) nm, α=β=γ=90°, V=3.2792(10) nm³, Z=8, D_c=1.156 g/cm³, F(000)=1232, μ(MoKα)=0.412 mm^-1, F(000)=1232, S=0.952, R=0.0664, wR=0.1791 [I>2σ(I)]. One-dimensional channel supramolecular network structure is formed by N-H••••S and C-H••••S interactions in the PDP crystal. PDP as a novel corrosion inhibitor for carbon steel in HCl solution was evaluated by mass loss measurement, potentiodynamic polarization, and electrochemical impedance spectroscopy. The results show that PDP acts as a mixed type inhibitor with cathodic inhibition as the dominative action. The adsorption of PDP on carbon steel surface obeys Langmuir isotherm, and the corrosion inhibition belongs to both physi- and chemisorptions. The inhibition efficiency is up to 98.9% with PDP concentration of 140 mg/L in 1.0 mol/L HCl solution at 25 ℃.