ISSN 2305-6894

2017, Vol. 6, Issue 1 (pp. 1–90)

Effect of the structure of o,o´-dihydroxyazo compounds on bactericidal and inhibitory ability

      • V.I. Vigdorovich,1 A.N. Zavershinskii,2 L.E. Tsygankova,2 T.N. Nazina,3 M.N. Esina2 and N.V. Shel4
1All-Russian Scientific Research Institute of Use of Machinery and Oil Products, 392022 Tambov, Russia
2Derzhavin State University, ul. Internatsyonalnaya, 33, 392000 Tambov, Russian Federation
3Winogradsky Institute of Microbiology, Russian Academy of Sciences, Leninsky prosp., 33, bldg. 2, 119071 Moscow, Russian Federation
4Tambov State Technical University, ul. Sovetskaya, 106, 392000 Tambov, Russian Federation

Abstract: The paper is devoted to a study of the influence of the molecule structure of a number of o,o´- dihydroxyazo (DHA) compounds on their bactericidal ability toward sulfate-reducing bacteria (SRB) in the Postgate medium at small concentrations (5–20 mg/L). DHA compounds induce a decrease in number of bacterial cells, H2S production by SRB, and hydrogen permeation into carbon steel in the presence of SRB. The inhibition of steel corrosion in the bacterial medium by these substances is considered as well.

Int. J. Corros. Scale Inhib., 2017, 6, no. 1, 1-17 (PDF 1127 K)
doi: 10.17675/2305-6894-2017-6-1-1

Study of surface morphology and inhibition efficiency of mild steel in simulated concrete pore solution by lactic acid–Zn2+ system

      • P.N. Devi,1 J. Sathiyabama1 and S. Rajendran1,2
1PG and Research Department of Chemistry, GTN Arts College, Dindigul-624005, India
2Corrosion Research Centre, Department of Chemistry, St Antony’s College of Arts and Sciences for Women, Amala Annai Nagar, Thamaraipadi (Post),
Dindigul – 624 005, Tamilnadu, India

Abstract: The inhibition efficiency (IE) of lactic acid–Zn2+ system in controlling corrosion of mild steel in simulated concrete pore solution (SCPS) prepared in well water in the absence and presence of Zn2+ has been investigated by weight loss study. The formulation consisting of 250 ppm of lactic acid and 50 ppm of Zn2+ provides 94% of inhibition efficiency. Inhibition was found to increase with an increasing concentration of lactic acid and Zn2+. Polarization resistance was measured by weight loss method, polarization study. The surface morphology has been investigated by SEM and AFM.

Int. J. Corros. Scale Inhib., 2017, 6, no. 1, 18-31 (PDF 942 K)
doi: 10.17675/2305-6894-2017-6-1-2

Controlling copper-based fouling by maleic acid and acrylic acid based copolymers in cooling water systems

      • A. Kweik,1 G. Nicolas,1 Z. Amjad1 and P.G. Koutsoukos2
1Department of Chemistry, Division of Mathematics and Sciences, Walsh University, N. Canton, Ohio 44720, USA
2Chemical Engineering Department, University of Patras and FORTH-ICEHT, GR-265040 Patras, Greece

Abstract: The influence of polymer architecture for copper(II) ions stabilization was studied in an aqueous system. The polymers tested include: (a) homo-polymers of acrylic acid, maleic acid, itaconic acid, and vinyl pyrrolidone, and (b) co- and terpolymers of acrylic acid and maleic acid containing comonomers with different functional groups (i.e., carboxylic acid, sulfonic acid, ester, alcohol, etc.). It was found that polymers containing stronger acidic, aromatic, and bulkier groups contribute significantly to the performance of polymers. Results on the characterization of Cu(II) hydroxide particles formed in the absence and presence of polymers by scanning electron microscopy, X-ray diffraction, and particle size analyses are presented.

Int. J. Corros. Scale Inhib., 2017, 6, no. 1, 32-46 (PDF 1628 K)
doi: 10.17675/2305-6894-2017-6-1-3

High-temperature inhibitors of stainless steel corrosion in sulfuric acid solutions

      • Ya.G. Avdeev,1 D.S. Kuznetsov,2 M.V. Tyurina,1 S.V. Oleynik,2 and M.A. Chekulaev1
1K.E. Tsiolkovsky Kaluga state university, Stepana Razina str. 26, Kaluga, 248023 Russian Federation
2A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Leninsky pr. 31, Moscow, 119071 Russian Federation

Abstract: The corrosion of chromium-nickel steel 08Kh18N10T in 2 M H2SO4 has been studied in a broad temperature range, t = 0–200°C. Under these conditions, the metal corrosion is enhanced with an increase in t to reach 9.7 kg/(m2•h) at 200°C. It has been shown that a formulation of IFKhAN-92 inhibitor (a substituted triazole) with KI in a molar ratio of 1:1 protects this steel in 2 M H2SO4 at temperatures up to 140°C, inclusive. The three-component mixture of IFKhAN-92, KI and urotropine (1:1:4) is more promising in this respect, as it efficiently inhibits corrosion at temperatures up to 180°C and allows the protective effect to be maintained for at least 8 h. This formulation also reliably protects low-carbon steel 20 in 2 M H2SO4 at temperatures up to 180°C, inclusive; what is more, corrosion slows down with time in the presence of this mixture.

Int. J. Corros. Scale Inhib., 2017, 6, no. 1, 47-58 (PDF 1251 K)
doi: 10.17675/2305-6894-2017-6-1-4

Corrosion inhibitors for reinforced concrete structures: a study of binary mixtures

      • A. Brenna, F. Bolzoni, MP. Pedeferri and M. Ormellese
Politecnico di Milano, Dipartimento di Chimica, Materiali e Ingegneria Chimica “Giulio Natta”, Via Mancinelli 7, 20131 Milano, Italia

Abstract: Corrosion inhibitors are used to prevent or delay corrosion of steel reinforcement in concrete. Available commercial products are of inorganic nature based on sodium nitrite (acknowledged to be the most effective product), or organic mixtures based on amines, alkanolamines, fatty acids and carboxylic substances. During the last 15 years in our laboratories an intense experimental research aimed at identifying new organic substances or mixtures thereof that might have greater inhibiting effectiveness on corrosion by chlorides. This paper present the results of electrochemical tests carried out in alkaline solution, in the presence of chlorides, that were conducted on binary mixtures made with three substances (nitrite, DMEA and benzoate). Electrochemical tests (namely potentiodynamic and potentiostatic polarisation) were carried out. Some of the mixtures exhibited a marked synergistic effect in the potentiodynamic polarisation tests, with a clear-cut increase in the pitting potential. In potentiostatic polarisation the effect on the critical chloride concentration for the initiation of localised corrosion were limited.

Int. J. Corros. Scale Inhib., 2017, 6, no. 1, 59-69 (PDF 1249 K)
doi: 10.17675/2305-6894-2017-6-1-5

Investigation of corrosion pattern of AISI 316 and AISI 304 stainless steels in Na2B4O7·5H2O solution

      • M. Akgul,1 H. Gerengi,2 O. Camlibel3 and M. Sahin4
1Department of Materials and Metallurgical Engineering, Seydişehir A. Cengiz Faculty of Engineering, Necmettin Erbakan University, 42370 Konya, Turkey
2Corrosion Research Laboratory, Department of Mechanical Engineering, Faculty of Engineering, Duzce University, 81620 Duzce, Turkey
3Department of Materials and Materials Processing Technology, Kırıkkale University, Kırıkkale Vocational School, 71450 Kırıkkale, Turkey
4Department of Energy System Engineering, Faculty of Engineering and Natural Sciences, Yıldırım Beyazıt University, 06010 Ankara, Turkey

Abstract: The corrosion behaviour of AISI 316 and AISI 304 stainless steels in Na2B4O7·5H2O solutions with various concentrations (3%, 6% and 9% w/w) commonly used in wood industry was investigated by using electrochemical impedance spectroscopy and polarisation techniques. The results reveal that the dissolution pattern of the studied steel samples is in the order 3% > 6% > 9%. The AISI 316 stainless steel is found to exhibit better corrosion resistance than the 304-type stainless steel alloy.

Int. J. Corros. Scale Inhib., 2017, 6, no. 1, 70-81 (PDF 1074 K)
doi: 10.17675/2305-6894-2017-6-1-6

Corrosion and electrochemical behavior of steel in hardening concrete

      • I.A. Gedvillo, A.S. Zhmakina, N.N. Andreev and S.S. Vesely
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Leninsky pr. 31, Moscow, 119071 Russian Federation

Abstract: It has been shown using corrosion and electrochemical methods that reinforcing steel is subject to pitting during the initial period of concrete hardening. It is intensified if chlorides are present in the tempering water and/or if corrosion products exist on the metal surface. IFKhAN-80 inhibitor added with tempering water hinders pit formation on steel during concrete hardening, up to complete suppression of this process. Even at high chloride concentrations and in the presence of corrosion products on the metal surface, reinforcing steel in concrete is passivated some time after concrete tempering.

Int. J. Corros. Scale Inhib., 2017, 6, no. 1, 82-90 (PDF 1898 K)
doi: 10.17675/2305-6894-2017-6-1-7