Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Inhibitor

Green Corrosion Inhibitor for Protection of Mild Steel

S.A. Ajeel

Engineering and Technology Journal, 2017, Volume 35, Issue 9, Pages 914-921

In the present work, corrosion inhibition of Mild steel in 1M H2SO4 solution by Rosmarinus Officinalis Leaves extract was studied by weight loss and potentiostatic methods. Increasing acid concentration leads to an increase in the corrosion rate of the electrode. The variable conditions used in this investigation are (100 to 1000 ppm at 25oC. Rosmarinus Officinalis Leaves extract for Mild steel. It has been found that the concentrates as a compelling consumption inhibitor for gentle steel in acidic medium. The hindrance process is credited to the development of an adsorbed film of inhibitor on the metal surface, which secures the metal against corrosion. The inhibition efficiency was observed that increase with increasing inhibitor concentration up to maximum 92% for 1000 ppm at 25 oC. The results show that the corrosion rate without inhibitor is 5.6 mpy while with inhibitor be 0.43 mpy, that is mean the corrosion rate was improved more than 90%. The effects of immersion time (2 h) at 25oC on the inhibition of corrosion have also been improved corrosion resistance. The results obtained show that Rosmarinus Officinalis Leaves Extract could serve as an excellent friendly green corrosion inhibitor. FTIR results indicate that this herb containing different chemical bonds (C-C, CH2, C-O-C, Cellulose) with steel surface producing barrier layer to protect the surface

Design of Nano-Inhibitor of Dichlorobenzene and It's Adduct and Study of Its Structural and Electronic Properties: DFT Calculations

A.D. Thamir; A.S. Hasan; A.L. Abed; F.Q. Mohammed

Engineering and Technology Journal, 2017, Volume 35, Issue 8, Pages 795-800

Corrosion in oil pipelines is one of the biggest problems in the oil sector companies because of the high cost resulted from repairing the corroded parts, or replace it with another non-corroded ones, so, in this research, we study the design of nano-inhibitor and study of its structural and electronic properties of dichlorobenzene molecule (C6H4Cl2) and the effect of adding groups of Hydroxy on those properties, density functional theory (DFT) at B3LYP level with (6-31G) basis sets. The study included four new molecules, which are including monohydroxy dichlorobenzene molecule, dihydroxy dichlorobenzene, trihydroxy dichlorobenzene, and tetrhydroxy dichlorobenzene. The structural and electronic calculations have been done by using Gaussian 09 program and Gaussian View in DFT calculations. The geometry optimization using both methods for dichlorobenzene (nano-inhibitor) and group’s Hydroxy molecules has been found in good agreement with experimental data. While the electronic properties included calculate total energy, ionization potential, electron affinity, chemical potential, electronegativity, electrochemical hardness and electronic softness for molecules under study. These results show that the energy gap reduced with the increase of the number of groups; also, the electron affinity and electronegativity for dichlorobenzene molecule Ben-Cl-2OH are the lowest, while the chemical potential be the highest for the same inhibitor. Nano-inhibitor result reduces corrosion of internal surfaces of tubes that used for transporting oil and gas to the importance of these molecules in terms of their high ability for interaction. Those dichlorobenzene can restrain corrosion from claiming steel toward framing an inactive layer for this molecule on the metal's surface.