Steel in hydrochloric acid

N— compounds used as acid inhibitors include heterocyclic bases, such as pyridine, quinoline and various amines. Carassiti describes the inhibitive action of decylamine and quinoline, as well as phenylthiourea and dibenzyl-sulphoxides for the protection of stainless steels in hydrochloric acid pickling. Hudson e/a/. refer to coal tar base fractions for inhibition in sulphuric and hydrochloric acid solutions. Good results are reported with 0-25 vol. Vo of distilled quinoline bases with addition of 0 05m sodium chloride in 4n sulphuric acid at 93°C. The sodium chloride is acting synergistically, e.g. 0-05m NaCl raises the percentage inhibition given by 0-1% quinoline in 2n H2SO4 from 43 to 79%. Similarly, potassium iodide improves the action of phenylthiourea . 

R.C. Newman and T. Shahrabi, The Effect of Alloyed Nitrogen or Dissolved Nitrate Ions on the Anodic Behavior of Austenitic Stainless Steel in Hydrochloric Acid, Corros. Sci., Vol 27, 1987, p 827-838... 

In the process of pickling, rust is removed from newly produced steel by washing the steel in hydrochloric acid ... 

The importance of this problem is underlined by the data in Table 4 concerning the behaviour of ARMCO iron in 1 N HCl solutions inhibited with the commercial product Borg P16 at a temperature of 75 °C. Borg P16 is a specific commercial inhibitor of the corrosion of iron and carbon steels in hydrochloric acid solutions and is a derivative of the commercial product Rodine 213. This inhibitor is used both for the acid cleaning of steam generators and for pickling baths. 

The effect of sensitizing temperature on SCC of type 316 ausenitic stainless steel in hydrochloric acid was investigated by Nishimura et al. [97] by using a constant load method. The authors form the applied stress dependence of three parameters steady state elongation rate, (4s), time interval of SCC-dominated failure, (4s), time of failure, (t, and divided the relationship between stress and the parameters into three regions. 

R. Nishimura, I. Musalam, Y. Maeda, The effect of sensitizing temperature on stress corrosion cracking of type 316 austenitic stairdess steel in hydrochloric acid solution, Corros. Sci. 44 (2002) 1343-1360. 

M.A. Quraishi, A. Singh, V.K. Singh, D.K. Yadav, A.K. Singh (2010). Green approach to corrosion inhibition of mild steel in hydrochloric acid and sulphuric acid solutions by the extract of Murraya koenigii leaves. Materials Chemistry and Physics 122(1), pp. 114-122. 

O.K. Abiola, N.C. Oforka, S.S. Angaye, TO. Braide (2005). Inhibition of corrosion of mild steel in hydrochloric acid solution. Journal of Corrosion Science and Technology 2, p. 116. 

J.C. da Rocha, J.A. da Cunha Ponciano Gomes, E. D Eha (2010). Corrosion inhibition of carbon steel in hydrochloric acid solution by fruit peel aqueous extract. Corrosion Science 52(7), pp. 2341-2348. 

S. Fuhua, W. Xiutong, Y. Jianqiang, H. Baorong, Corrosion Inhibition by Polyaniline Copolymer of Mild Steel in Hydrochloric Acid Solution. Anti-Corros. Methods Mater. 2011,58,111-115. 

Ashassi-Sorkhabi, H., B. Shaabani, and D. Seifzadeh, Effect of some pyrimidinic Schiff bases on the corrosion of mild steel in hydrochloric acid solution. Electrochimica Acta, 2005. 50 (16-17) p. 3446-3452. 

Khaled, K.F., Experimental and theoretical study for corrosion inhibition of mild steel in hydrochloric acid solution by some new hydrazine carbodithioic acid derivatives. Applied Surface Science, 2006. 252(12) p. 4120- 128. 

Emregul, K.C. Hayvali, M. (2002). Studies on the effect of vanillin and photocatechualdehyde on the corrosion of steel in hydrochloric acid. Materilas Chemisty Physics 83 209-216. 

Li XH, Deng SD, Mu GN, Fu H (2010a) Synergism between protocatechualdehyde and rare earth cerium(IV) ion on the corrosion of cold rolled steel in hydrochloric acid soltxXiovC. Materials and Corrosion 61,. ... 

Mu GN, Zhao TP (2004) Synergistic effect on corrosion inhibition by cerium (IV) ion and sodium molybdate for cold rolled steel in hydrochloric acid solution Acta Chimica Sinica 62,24, 2386-2390. 

I A system (A) consists of an unloaded coil spring of steel immersed in hydrochloric acid. A system (B) consists of a similar, but compressed coil spring of steel in hydrochloric acid. After some time, both of the steel springs have been dissolved in the acid. What has happened to the potential energy Ep that was originally present in the spring (B) ... 

The corrosion rate of steel in carbonic acid is faster than in hydrochloric acid Correlations are available to predict the rate of steel corrosion for different partial pressures of CO2 and different temperatures. At high temperatures the iron carbonate forms a film of protective scale on the steel s surface, but this is easily washed away at lower temperatures (again a corrosion nomogram is available to predict the impact of the scale on the corrosion rate at various CO2 partial pressures and temperatures). 

Technetium is a silvery-gray metal that tarnishes slowly in moist air. The common oxidation states of technetium are +7, +5, and +4. Under oxidizing conditions technetium (Vll) will exist as the pertechnetate ion, TcOr-. The chemistry of technetium is said to be similar to that of rhenium. Technetium dissolves in nitric acid, aqua regia, and cone, sulfuric acid, but is not soluble in hydrochloric acid of any strength. The element is a remarkable corrosion inhibitor for steel. The metal is an excellent superconductor at IIK and below. 

Anodic protection is particularly suitable for stainless steels in acids. Protection potential ranges are given in Section 2.4. Besides sulfuric acid, other media such as phosphoric acid can be considered [13,21-24]. These materials are usually stable-passive in nitric acid. On the other hand, they are not passivatable in hydrochloric acid. Titanium is also a suitable material for anodic protection due to its good passivatability. 

Fabricated articles are less commonly hot-dip aluminised now than in the past. Coatings are applied after cleaning the work, e.g. pickling in hydrochloric acid in the case of steel and then preheating. The work is then immersed in a molten salt bath, a flux or reducing atmosphere, prior to... 

Direct measurements on metals such as iron, nickel and stainless steel have shown that adsorption occurs from acid solutions of inhibitors such as iodide ions, carbon monoxide and organic compounds such as amines , thioureas , sulphoxides , sulphidesand mer-captans. These studies have shown that the efficiency of inhibition (expressed as the relative reduction in corrosion rate) can be qualitatively related to the amount of adsorbed inhibitor on the metal surface. However, no detailed quantitative correlation has yet been achieved between these parameters. There is some evidence that adsorption of inhibitor species at low surface coverage d (for complete surface coverage 0=1) may be more effective in producing inhibition than adsorption at high surface coverage. In particular, the adsorption of polyvinyl pyridine on iron in hydrochloric acid at 0 < 0 -1 monolayer has been found to produce an 80% reduction in corrosion rate . 

F. B. Growcock and V. R. Lopp. The inhibition of steel corrosion in hydrochloric acid with 3-phenyl-2-propyn-l-ol. Corrosion Sci, 28(4) 397-410,1988. 

Rust of iron (the most abundant corrosion product), and white rust of zinc are examples of nonprotective oxides. Aluminum and magnesium oxides are more protective than iron and zinc oxides. Patina on copper is protective in certain atmospheres. Stainless steels are passivated and protected, especially in chloride-free aqueous environments due to a very thin passive film of Cr2C>3 on the surface of the steel. Most films having low porosities can control the corrosion rate by diffusion of reactants through the him. In certain cases of uniform general corrosion of metals in acids (e.g., aluminum in hydrochloric acid or iron in reducible acids or alkalis), a thin him of oxide is present on the metal surface. These reactions cannot be considered hlm-free although the him is not a rate-determining one.1... 

Filter Stick Use either a 10-mm diameter sintered-glass filter stick of 10- to 15-pm maximum pore diameter, or a filter stick made of stainless steel and having a 0.5-in. disk of 10- to 15-pm maximum pore diameter. Determine conformance with the pore diameter specified as follows Clean sintered-glass filter sticks by soaking in hydrochloric acid, or stainless steel sticks by soaking in nitric acid, wash with water, rinse with acetone, and dry in air followed by drying in an oven at 105° for 30 min. 

In the analysis of tungsten steels the sample may be dissolved in hydrochloric acid or dilute sulphuric acid in absence of air. The tungsten remains undissolved and is ignited, fused with sodium carbonate, and estimated by ordinary methods. ... 

Properties Iron-black to dark steel-gray or bluish mineral black or bluish-black streak metallic or dull luster. D 4.73 1.86, Mohs hardness 2-2.5. Soluble in hydrochloric acid. 

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