H_3PO_4中染料中性红对钢的缓蚀性能

Inhibition Effect of Neutral Red on Cold Rolled Steel in H_3PO_4 Solution

用失重法研究了染料中性红对冷轧钢在1.0 mol/LH3PO4溶液中的缓蚀作用。结果表明:中性红对冷轧钢在1.0 mol/LH3PO4溶液中具有良好的缓蚀作用。缓蚀率先随缓蚀剂浓度的增加而增大,后减小,存在浓度极值现象;缓蚀率随温度的升高而增大。在吸附区间(25～150 mg/L)中性红在钢表面的吸附符合Temkin吸附等温式。通过热力学基本公式求出了相应的吸附热力学(吸附自由能△G0,吸附焓△H0,吸附熵△S0);根据这些参数讨论了缓蚀作用机理。

The adsorption and inhibition effect of neutral red on cold rolled steel（CRS） in 1.0mol/L H3PO4 solution at 20℃~50℃ was investigated by weight loss method.The results show that neutral red is a good inhibitor for CRS in H3PO4 solution.Inhibition efficiency increases the inhibitor concentration,then decreases.In other words,there is an extreme-value-phenomena of inhibitor concentration.The adsorption of neutral red on CRS surface obeys Temkin adsorption isotherm equation with the adsorption concentration range（25~150mg/L）.Three adsorption thermodynamic parameters（adsorption free energy ΔG0,adsorption heat ΔH0,adsorption entropy ΔS0） are also calculated by the thermodynamic basic equation.The inhibitive mechanism is discussed according to the parameters.