Study On The Preparation And Properties Of Environmentally Water-based Rust Inhibitor

Since metal corrosion causes dramatic economic loss and even endangers life safety,thus the corrosion resistance of metal has been increasingly demanded in the market.Rust inhibitor is one of the most common and most effective ways to prevent metal corrosion currently.With the growing of environmental consciousness and awareness of energy conservation,the safe and environmentally friendly water-based rust inhibitor has attracted much attention.In this study,Q235 steel rebar with ubiquitous rust corrosion problems is used.An environmentally friendly water-based anti-lot was prepared with sodium silicate as raw materials by single factor and orthogonal experiments.Its antiseptic properties were tested by a variety of characterization methods such as the outdoor exposure test,static corrosion experiment,indoor accelerated experiment method,electrochemical methods and scanning electron microscopy(SEM).Formula(wt.%)of the self-made anti rust agent was explored by single factor and orthogonal experiments.The weight ratios of sodium silicate,additives,elhylene diamine tetraacetic acid,sodium benzoate,six methyl tetramine and boric acid were 35%,1.5%,1%,0.6%,3%and 0.45%,respectively.The pH measured by pH meter,surface tension measured by the method of suspension link and the coating thickness of the anti-rust agent were 11.6,43mN·m-1 and 7.33um,respectively.The immersion time in NaCl solution(3%)reached 12h.Tafel polarization curves show that the anti-rust agent coating not only can significantly improve the corrosion potential,with the blank steel sheet's potential transformed from-0.7094V to-0.4206V,but also can significantly reduce the corrosion current density,which transformed froml.87×10-5A·cm-2 to 9.12×10-7A·cm-2.Furhermore,the corrosion rate was reduced from 1.30×10-19·m-2·h-1 to 6.35×10-9g·m-2·h-1,which was reduced by about two orders of magnitude.EIS results show that the self-made anti rust agent can significantly increase the charge transfer resistance,which increased from 66 Q·cm-2 to 325 Q·cm-2.The outdoor experiment results show that the self-made can prevent rebar from rusting for more than two months and carbon steel from rusting for one month.In addition,the indoor experiment indicates that the self-made can prevent carbon steel from rusting for more than five months.In summary,the self-made anti-rust agent can play a good role in anti-corrosion and the advantage of low cost make it potential in application.