Preparation And Properties Of New Inorganic Corrosion Inhibitors

The steel materials are wildly used in life and industrial production.However, the steel materials have to contact with all kinds of corrosive medium during the using process, so that it is easy to be corroded. This will not only lead to huge economic losses, but also threaten people's lives because of serious security incidents. Therefore, it is a long-term, urgent and important work to study the anti-corrosion of steel materials.As the corrosion inhibitor has the advantages of convenient operation, low cost, quick effect, and it has become an economical and effective method. Tungstate, rare earth salt, tin salt and titanium salt because of low toxicity, no pollution has become a research hotspot of new inorganic corrosion inhibitor. At present, due to the performance of tungstic acid salt and rare earth salt alone usage is not stable, to a certain extent, this limits the tungstic acid salt and rare earth salt corrosion inhibition agent in industrial application, so this research mainly concentrated on the idea of compound. In addition, tin salt and titanium salts as corrosion inhibitor for carbon steel corrosion research is also small, but they clearly have potential as a corrosion inhibitor because of their physical and chemical characteristics. The above four kinds of inorganic salts are not only in theory, but also have a great advantage in our country's resource reserves. Therefore, it is of great theoretical and practical significance to study the preparation and properties of the corrosion inhibitor for the above four kinds of inorganic salts.In this paper, the corrosion inhibition performance of X80 pipeline steel was studied in three kinds of medium (sodium chloride, hydrochloric acid, phosphoric acid) by the compound of sodium and cerium, and neutral red was carried out to further improve the corrosion inhibition effect of W-Ce inhibitor in acid mediun. In the second, the SnSO4 inhibitor on X80 steel was prepared in the hydrochloric acid solution with pH value of 1, and the corrosion inhibition mechanism of the corrosion inhibitor was studied. Finally, the anti-corrosion effect and mechanism of the TiOSO4 inhibitor for X80 pipeline steel was explored. Weight-loss method is used to study the inhibition efficiency of inhibitor in different systems, macro morphology observation and electrochemical tests are combined to evaluate and analyze the inhibition effect of composite inhibitors,X-ray spectrometer is used to make analysis for the micro area of protective film on the surface of X80 pipeline steel samples for the qualitative and quantitative analysis for the elements contained in the protective film,X-ray diffraction is used to analyze the phase of the film on the surface of the sample, and the composition of the film was determined. The results showed that:the anti-corrosion action of W-Ce compounded inhibitor on X80 steel produces excellent corrosion inhibition effect in sodium chloride solution,which is mainly got by a layer of corrosion film.The film is formed from heteropoly acid [Ce(WO4)3]n3-through Ce3+ and WO42- and coordinates with Fe, adsorbing on the surface of steel to isolate corrosion medium. Neutral red can make inhibition performance of W-Ce compound inhibitor improve significantly on X80 pipeline steel in hydrochloric acid and phosphoric acid solution. This is not only because of neutral red molecule itself with Fe occurs adsorption of coordination chemistry, but also because of its N atom can be respectively with Ce3+ and WO42- empty track action form macromolecular complexes and adsorbed on the surface of the steel to isolate the corrosive medium. The corrosion inhibition effect of SnSO4 inhibitor on X80 pipeline steel was achieved by Sn2+ ions reducted and precipitated on the surface of X80 steel, which formed the corrosion inhibitor membrane,and it isolated from the contact of corrosion media and steel surface. Titanyl sulfate inhibitor has a certain extent corrosion inhibition effect on X80 pipeline steel, which is mainly reason that the partial titanium ions on the oxygen atom with iron atoms on the surface of the steel occur coordination role, resulting in a chemical adsorption, but the restriction of the number of electrons in the isolated pair, corrosion inhibition performance is in general.