2-(苄硫基)苯并咪唑与2-(对氯苄硫基)苯并咪唑的合成及缓蚀性能研究

Synthesis and Inhibitory Performance of BSBD and CBSBD Corrosion Inhibitors

合成了2-(苄硫基)苯并咪唑(BSBD)和2-(对氯苄硫基)苯并咪唑(CBSBD),并通过元素分析和红外光谱对其结构进行了表征。采用失重法和电化学法研究了BSBD和CBSBD在5%HCl溶液中对Q235钢的缓蚀性能。失重法研究表明:BSBD和CBSBD在HCl溶液中均能有效抑制Q235钢腐蚀,在25°C、5%CHl溶液中,两者浓度均为50 mg/L时,其缓蚀率分别达到98.37%和98.47%;电化学研究结果表明:两者均属高效混合型缓蚀剂。另外,两者在Q235钢表面的吸附完全符合Langmuir吸附温式,吸附过程自由能ΔG0a为41.04 kJ/moL和41.76 kJ/moL,说明在Q235钢表面吸附均为自发进行的化学吸附。

2-Benzylsulfenyl-1H-benzimidazole（BSBD）and 2-（p-chlorobenzylsulfenyl）-1H-benzimidaz-ole（CBSBD） have been synthesized and characterized by elemental analysis and IR spectroscopy.Their inhibition efficiency towards the corrosion of Q235 steel in 5%HCl solution have been investigated by weight loss and potentiodynamic polarization techniques.The weight loss studies show that the inhibition efficiencies of BSBD and CBSBD are up to 98.37% and 98.47% respectively when the inhibitors concentration are 50 mg/L in 5% HCl solution at 25°C.Potentiodynamic polarization measurements show that the BSBD and CBSBD are mixed-type inhibitors in 5% HCl solution.The adsorption of BSBD and CBSBD on Q235 steel surface is consistent with the Langmuir adsorption isotherm,and the obtained standard free energy of adsorption indicates that spontaneous chemisorption takes place.