在酸性介质中脐橙皮提取物对不锈钢的缓蚀作用

doi:10.11902/1005.4537.2022.214

中国腐蚀与防护学报

2023, Vol. 43

Issue (3): 619-629 CSTR: 32134.14.1005.4537.2022.214 DOI: 10.11902/1005.4537.2022.214

研究报告

本期目录 | 过刊浏览

在酸性介质中脐橙皮提取物对不锈钢的缓蚀作用

周坤¹, 柳鑫华²(

), 刘帅²

^1.河北化工医药职业技术学院石家庄 050026
^2.唐山师范学院化学系唐山 0630000

Corrosion Inhibition of Navel Orange Peel Extract to Stainless Steel in Acidic Medium

ZHOU Kun¹, LIU Xinhua²(

), LIU Shuai²

^1.Hebei Chemical & Pharmaceutical College, Shijiazhuang 050026, China
^2.Department of Chemistry, Tangshan Normal University, Tangshan 063000, China

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摘要:

选用脐橙皮提取物 (NOPE) 作为HCl环境中316L钢的缓蚀剂。通过简单的乙醇-丙酮回流法提取获得NOPE。通过红外光谱和紫外光谱验证了脐橙皮提取物的主要成分及其在盐酸中的稳定性。采用失重法、动态电位极化法、线性极化和电化学阻抗谱法研究了NOPE在0.5mol/L HCl溶液中对316L钢的缓蚀性能。通过 $Δ G a d s 0$ 、 $Δ H a d s 0$ 和 $Δ S a d s 0$ 对它们的吸附性能进行了计算。结果表明，随着NOPE浓度的增加，腐蚀速率的降低，阳极电流的减少和活性腐蚀部位的阻断，使缓蚀效率提高。当NOPE的加入量为0.5 g/L时，体系的缓蚀效率最高为90.5% (失重法) 和87.3% (电化学法)。与空白体系相比，添加NOPE后，体系的热力学活化参数 (活化能) E_a明显增大，(E_a- $Δ H a 0$ ) 的差值约等于RT的平均值 (2.64 kJ/mol)，因此，可以推断，腐蚀过程为单分子反应。采用Langmuir等温线拟合金属表面的吸附过程，进一步证明了该吸附为单分子层吸附。通过扫描电镜和能谱分析证明了NOPE在钢表面的作用降低了316L钢的酸腐蚀。在0.5 mol/L HCl溶液体系中，NOPE对L316钢具有较好的缓蚀性能，是一种在酸洗领域中有着较好应用前景的绿色缓蚀剂，可以为植物提取类缓蚀剂的发展提供一定的指导。

关键词 ：脐橙皮提取物, 缓蚀剂, 极化, 阻抗, 表面分析

Abstract：

To promote the rapid development of green plant extract inhibitor, navel orange peel extract (NOPE) was obtained by a simple ethanol-acetone reflux method, which then was assessed as inhibitor for 316L steel in hydrochloric acid medium. The main components of navel orange peel extract (NOPE) and its stability in hydrochloric acid were confirmed by infrared spectroscopy (FTIR) and ultraviolet spectroscopy (UV). The corrosion inhibition performance of NOPE to 316L steel in 0.5 mol/L HCl solution was investigated using mass loss method, dynamic potential polarization method (PDP), linear polarization method (LPR) and electrochemical impedance spectroscopy (EIS). Their adsorption properties were calculated with items of $Δ G a d s 0$ , $Δ H a d s 0$ and $Δ S a d s 0$ . The results show that with the increase of the concentration of NOPE, the steel corrosion rate is reduced, the anode current is reduced and the active corrosion site is blocked, so the inhibition efficiency is improved. When the concentration of NOPE was 0.5 g/L, the maximum corrosion inhibition efficiency was 90.5% (masslessness method) and 87.3% (electrochemical method) respectively. Compared with the blank system, the thermodynamic activation parameter (activation energy) E_a significantly increased in the system with NOPE, and the difference of (E_a- $Δ H a 0$ ) was about equal to the average value of RT (2.64 kJ/mol). Therefore, it can be inferred that the corrosion process was a single molecule reaction. The adsorption process on the steel surface was fitted by Langmuir isotherm, which further proved that the adsorption was monolayer adsorption. The better corrosion inhibition performance of NOPE for L316 steel in 0.5 mol/L HCl solution system can also be proved by the observation and detection with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). In sum, the NOPE is a green inhibitor with a good application prospect in the field of pickling and can provide certain guidance for the development of plant extract inhibitor.

Key words： navel orange peel extract corrosion inhibitor polarization impedance surface analysis

收稿日期: 2022-06-29 32134.14.1005.4537.2022.214

ZTFLH:

TG174

基金资助:河北省自然科学基金(D2022105004);唐山师范学院基金项目(2022C42)

通讯作者: 柳鑫华，E-mail：hualiyiwang@163.com，研究方向为绿色水处理剂

Corresponding author: LIU Xinhua, E-mail: hualiyiwang@163.com

作者简介: 周坤，男，1979年生，硕士，讲师

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引用本文:

周坤, 柳鑫华, 刘帅. 在酸性介质中脐橙皮提取物对不锈钢的缓蚀作用[J]. 中国腐蚀与防护学报, 2023, 43(3): 619-629.
ZHOU Kun, LIU Xinhua, LIU Shuai. Corrosion Inhibition of Navel Orange Peel Extract to Stainless Steel in Acidic Medium. Journal of Chinese Society for Corrosion and protection, 2023, 43(3): 619-629.

链接本文:

https://www.jcscp.org/CN/10.11902/1005.4537.2022.214 或 https://www.jcscp.org/CN/Y2023/V43/I3/619

图1 NOPE的FTIR图和有无盐酸介质的UV图

图2 NOPE中的橙皮苷与简单黄酮结构式

表1 失重法计算得出的Vi 值和ƞi 值

图3 316L钢在空白和含有NOPE的0.5 mol/L HCl溶液中的Arrhenius图和碳钢溶解反应的过渡态图

ContentC_inh / mg·h^-1	Amg·h^-1·cm^-2	E_akJ·mol^-1	ΔH $a 0$ kJ·mol^-1	ΔS $a 0$ J·mol^-1·K^-1
0	7.56×10⁶	58.30	55.66	-139.35
30	3.89×10⁸	70.18	67.54	-89.34
50	1.34×10⁹	73.79	71.15	-79.07
100	1.98×10¹⁰	81.52	78.88	-56.68
200	2.81×10¹⁰	82.75	80.11	-53.78
300	5.47×10¹¹	91.40	88.76	-29.07
500	3.32×10¹²	96.54	93.90	-14.08

表2 316L钢在空白和含有NOPE的0.5 mol/L HCl溶液中热力学活化参数

图4 NOPE在0.5 mol/L HCl溶液中对316L钢的Langmuir吸附等温线

T / K	K_ads / L·g^-1	R²	$Δ G a d s 0$ / kJ·mol^-1
303	35.97	0.9987	-26.43
313	25.38	0.9977	-26.39
323	18.38	0.9937	-26.37
333	14.31	0.9958	-26.49

表3 不同温度下，在0.5 mol/L HCl溶液中316L钢表面对NOPE的吸附热力学参数

图5 在0.5 mol/L HCl中316L钢对NOPE吸附的lnKads与T-1关系图

图6 316L钢在0.5 mol/L HCl溶液中加入不同浓度NOPE和不加入NOPE的EOCP-t的曲线

表4 316L钢在0.5 mol/L HCl溶液中加入和不加入不同浓度的NOPE时的动态电位极化和线极化数据

图7 316L钢在含不同浓度NOPE的0.5 mol/L HCl溶液中的动电位极化曲线

图8 NOPE阻止活性位点示意图

图9 316L钢在不同浓度NOPE的0.5 mol/L HCl介质中的阻抗谱及等效电路

表5 316L钢在含不同浓度NOPE的0.5 mol/L HCl介质中的EIS拟合参数

图10 316L钢试片表面的SEM照片和EDS分析结果

图11 316L钢在含NOPE的0.5 mol/L HC溶液中的缓蚀机理

表6 HCl溶液中用于钢的提取物缓蚀剂的比较

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