Ramachandran, Sunder and Tsai, Bao-Liang and Blanco, Mario and Chen, Huey and Tang, Youngchun and Goddard, William A., III (1996) Self-Assembled Monolayer Mechanism for Corrosion Inhibition of Iron by Imidazolines. Langmuir, 12 (26). pp. 6419-6428. ISSN 0743-7463. doi:10.1021/la960646y. https://resolver.caltech.edu/CaltechAUTHORS:20180719-161618054
Full text is not posted in this repository. Consult Related URLs below.
Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20180719-161618054
Abstract
Some of the most effective corrosion inhibitors for oil field pipeline applications are the oleic imidazoline (OI) class of molecules. However, the mechanism by which OIs inhibit corrosion is not known. We report atomistic simulations (quantum mechanics and molecular dynamics) designed to elucidate this mechanism. These studies lead to the self-assembled monolayer (SAM) model for corrosion inhibition, which explains the differences in corrosion inhibition efficiency for various OI molecules. The SAM model of OI inhibitors involves the following critical elements: (i) The function of the OI is to form a self-assembled monolayer on the native oxide surface of iron; this serves a protective role by forming a hydrophobic barrier preventing migration of H_2O, O_2, and electrons to the Fe surface. (ii) The imidazoline head group serves as a sufficiently strong Lewis base to displace H2_O from the Lewis acid sites of the iron oxide surface. (iii) These head groups self-assemble on the surface to form an ordered monolayer on the iron oxide surface. [√3 x √3 for the (001) cleavage surface of α-Fe_2O_3.] (iv) The long hydrophobic tail (e.g., 2-oleic acid) tilts to form a tightly packed hydrophobic monolayer. [For α-Fe_2O_3(001) the tilt angle is about 72° with respect to the surface normal.] (v) This hydrocarbon tail must have a sufficient length to cover the surface. [For α-Fe_2O_3(001) the chain length must be 12 or more carbon atoms.] (vi) The hydrophobic tail and the pendent group (e.g., −CH_2CH_2NH_2) must lead to an octanol/water partition coefficient (log P) below a critical value in order to rapidly form the monolayer. This SAM model should be useful in developing both alternative environmentally benign corrosion inhibitors and higher temperature corrosion inhibitors.
Item Type: | Article | ||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Related URLs: |
| ||||||||||||||||||||||||||||||
ORCID: |
| ||||||||||||||||||||||||||||||
Additional Information: | © 1996 American Chemical Society. Received June 27, 1996. The research was funded by Chevron Petroleum Technology Co. (R. Heming), by DOE-BCTR (D. Boron), and by NSF-GCAG (Grant ASC 92-17368, R. Hildebrand). The facilities of the MSC are also supported by grants from NSF-CHE (Grant 95-22179), Aramco, Asahi Chemical, Chevron Chemical Co., Asahi Glass, Owens-Corning, Hercules, BP Chemical, Chevron Research and Technology Co., Avery-Dennison, and Beckman Institute. Calculations for this project were carried out on the Illinois NSF Supercomputer Center (L. Smarr) and on the JPL Cray (P. Messina). | ||||||||||||||||||||||||||||||
Funders: |
| ||||||||||||||||||||||||||||||
Issue or Number: | 26 | ||||||||||||||||||||||||||||||
DOI: | 10.1021/la960646y | ||||||||||||||||||||||||||||||
Record Number: | CaltechAUTHORS:20180719-161618054 | ||||||||||||||||||||||||||||||
Persistent URL: | https://resolver.caltech.edu/CaltechAUTHORS:20180719-161618054 | ||||||||||||||||||||||||||||||
Official Citation: | Self-Assembled Monolayer Mechanism for Corrosion Inhibition of Iron by Imidazolines Sunder Ramachandran, Bao-Liang Tsai, Mario Blanco, Huey Chen, Yongchun Tang, and William A. Goddard, III Langmuir 1996 12 (26), 6419-6428 DOI: 10.1021/la960646y | ||||||||||||||||||||||||||||||
Usage Policy: | No commercial reproduction, distribution, display or performance rights in this work are provided. | ||||||||||||||||||||||||||||||
ID Code: | 88040 | ||||||||||||||||||||||||||||||
Collection: | CaltechAUTHORS | ||||||||||||||||||||||||||||||
Deposited By: | George Porter | ||||||||||||||||||||||||||||||
Deposited On: | 19 Jul 2018 23:26 | ||||||||||||||||||||||||||||||
Last Modified: | 16 Nov 2021 00:23 |
Repository Staff Only: item control page