Corrosion inhibitor technologies

Toxicity issues will continue to be some of the most important aspects of corrosion inhibitor technology, and meeting the demands for less toxic inhibitors will consume a large portion of the funds available to develop new formulations. Other issues such as flash point and presence of heavy metals will limit the palette available to the inhibitor formulator. A comprehensive review of "green" inhibitor technology was presented at the 2000 Ferrara, Italy inhibitor conference. ... 

Below 200-250°F, a corrosion inhibitor in proper concentration (0.1%-1%) is usually sufficient to inhibit acid corrosion. At higher temperatures, it may be necessary to include more inhibitor, as well as an inhibitor intensifier or booster. At temperatures of more than 3 GOT, an intensifier is almost always required. New developments in corrosion inhibitor technology will reduce the need for intensifiers in the future. 

Chemical Specialties Manufacturers Association 1001 Connecticut Avenue, NW Washington, D.C. 20036 Standard Reference TestingMaterials for insecticides (see Insect control technology), cleaning products, sanitizers, brake fluids, corrosion inhibitors (see Corrosion and corrosion control), antifreezes, poHshes, and floor waxes. 

The need to identify replacements for chromate-based technologies has also resulted in the development of alternatives to resin-based corrosion-inhibiting primers. These are primarily inorganic barrier coating techniques, such as sol-gel processes, which may or may not include corrosion inhibitors. These are discussed in a later section. 

Ranney, M. W., Corrosion Inhibitors Manufacture and Technology, Chemical Technology Review No 60, Noyes Data Corporation, New Jersey and London (1976)... 

Gandhi, Ashish (Cortec Corporation). Volatile Corrosion Inhibitors Unique Water Treatment Applications. The Analyst, Journal of the Association of Water Technologies, USA, Fall 2000. 

Ammonium salts of alkenyl succinic half-amides have teen described for use as corrosion inhibitors in oil and gas production technology to combat corrosion by media containing CO2, H2S, and elemental sulfur [1366]. The inhibitor composition may contain a dispersing agent, such as a low molecular weight or polymeric anionic surfactant like an alkylsulfonic acid or an alkyl-aryl sulfonic acid. 

M. A. Keimard and J. G. McNulty. Conventional pipeline-pigging technology Pt 2 Corrosion-inhibitor deposition using pigs. Pipes Pipelines Int, 37(4) 14-20, July-August 1992. 

K. Oppenlaender, B. Wegner, and W. Slotman. Ammonium salt of an alkenylsuccinic half-amide and the use thereof as corrosion inhibitor in oil and/or gas production technology. Patent US 5250225, 1993. 

However, azoles are commonly employed in cooling water formulations as yellow-metal corrosion inhibitors, and thus provide a potential source of interference. In addition, the technology monitors only the residual azole in the recirculating water and cannot directly provide an assurance of the integrity of the waterside metal, protective inhibitor film. Finally, TRASAR technology still requires periodic conventional wet tests for confirmation. 

Deng B., Hu S, and Burris D. R. (1998) Effect of iron corrosion inhibitors on trichloroethylene reduction. In Physical, Chemical, and Thermal Technologies (ed. G. B. Wickramanayake and R. R. Hinchee), pp. 341-346. Battelle Press. 

If the Amine Guard corrosion inhibitor is used, the MEA concentration in the circulating solution can be increased to 30 percent from a normal 20 percent. Hence, the circulating rate can be decreased by 33 percent and the heat requirements are decreased by 43 percent.69 The Amine Guard technology is licensed by UPO.200... 

As technology advances, the need for improved performance from materials increases. There is also a continuing economic pressure to minimise costs, which will become increasingly difficult as resources become depleted. Thus, research is aiming at more efficient corrosion protection methods such as improved formulations for paints and corrosion inhibitors, improved metal alloys, better design, and the use of novel materials such as ceramics and plastics. 

Fig. 12.1. Polarization curves for 7075 A1 in 0.1 M NaCl and in 0.1 M NaCl with 1000 ppm of various REM chlorides (from R.B.W. Hinton in Corrosion Inhibitor Science and Technology (1993), edited by A. Raman and P. Labine, 1-11-1. Copyright by NACE International. All rights reserved by NACE reprinted with permission).

Ranney, M. W. "Corrosion Inhibitors. Manufacture and Technology," Noyes Data Corporation Park Ridge, New Jersey,... 

It would appear that ozone has a significant potential as an additive to combat fouling, in particular as a biocide to reduce biofouling. More detailed work is required however to improve the technology and in particular, to optimise dosing requirements to improve cost effectiveness. Investigations of the use of ozone in relation to other additives, e.g. corrosion inhibitors are also necessaiy. 

The described system (Fig. 1.14) is implemented in the anticorrosion technology via active, adaptive and smart composites. The polymer matrix adds strength to the material and serves as a container for a corrosion inhibitor. The latter can move within the matrix in the liquid phase and liberate into the ambient medium. The channels through which the inhibitor is liberated match a regulation system, which is actuated either spontaneously or under control factors. The thermod mamically non-equilibrium composite structure starts to approach its equilibrium state as the inhibitor is liberated. This process is accompanied by dissipation of the energy accumulated in the composite during forming. 

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