Corrosion features inhibitors

Chem. Descrip. PTEE, paraffinic oil, MoSj, petroleum distillates (diluent) Uses Eilm lubricant coating corrosion/rust inhibitor Features Colorless for difficult-to-reach areas effective for freeing connectors frozen due to corrosion or chem. attack cleans as it lubricates, eliminates rust/corrosion Properties Low vise. 

Uses Antimicrobial, preservative, stabilizer, slimicide for use in latexes, emulsion paint, aq. slurries, adhesives, tape Joint compds., o/w emulsions, paper coatings, pesticides, water-based inks, hides and skins USDA approved for paints used in federally inspected plants and packing adhesives having min. contact with meat or poultry food prods. food pkg. adhesives, paper food-contact slimicide Features Inhibitor of bacteria, yeast, and fungi heat-stable, low corrosivity no formaldehyde released... 

Uses Corrosion/scale inhibitor used in various aq. systems (boiler feed water, recirculated cooling water) over wide temp, range dispersant for dyes, pigments, latex paints food pkg. adhesives, paper/paperboard Features Inhibits scale deposits on equip, surfs., promotes efficient heat transfer, decreases equip, damage Reguiatory FDA 21CFR 175.105,176.180 Properties Pale yel. clear liq. m.w. 15,000 dens. 9.2 Ib/gal vise. 19-182 cps f.p. 28 F pH 9.5-10.5 (10% aq.) surf. tens. 64 dynes/cm (0.1%) 24-26% total solids... 

Uses Sequestrant, corrosion/scale inhibitor, detergent for water treatment, detergents, pulp/paper processing, textile processing, bleach stabilization, sec. oil recovery and desalination crystal growth modifier Features Hydrolytic stability... 

Uses Cleaner for sanitary, domestic, vehicle, and food processing industries corrosion/scale inhibitor which eliminates min. deposits (scale, cement film, efflorescence) and colored corrosion or oxidized deposits Features High cleaning performance unaffected by hard water highly resistant in electrolyte sol ns. 

Uses Corrosion/rust inhibitor for aq. ferrous and nonferrous metalworking fluids Features Low foaming stable in hard water compat. with most aq. lubricants and antiseize compds. 

Uses Corrosion/rust inhibitor, buffer, stabilizer for aq. metalworking fluids Features Resist, to attack by bacteria, fungi, and yeast Properties Cl. vise, liq. sol. in water disp. in oils sp.gr. 1.05-1.15 (20 C) pH 9.8 (1% aq.)... 

Uses Emulsifier for o/w emulsions dispersant corrosion/rust inhibitor for protection of metal surfs. friction modifier detergent Features Provides extremely stable emulsions and polar media dispersions compat. with water and wide variety of polar soivs. 

Chem. Descrip. Oxidation and corrosion inhibitor in oil Uses Antioxidant, corrosion/rust inhibitor, metal deactivator, demulsifier for industrial oils, turbine oils, hydraulic oils, compressor oils Features No ozone-depleting substances... 

Chem. Descrip. Syn. and org. polymers and zinc corrosion inhibitors Uses Cooling water treatment, corrosion/scale inhibitor, dispersant for cooling towers cleans existing scale deposits and prevents further scaling Features Rec. for cooling towers utilizing makeup water that is < 10 grains/gal (170 ppm) total alkalinity... 

Consider first the corrosion of low alloy steel in HC1 per se, i.e. before the addition of organic inhibitors. As shown in Figures 1 and 2 for N80 steel in 15% and 28% HC1 at 65 C, Nyquist plots for steel in concentrated HC1 typically have only one distinct feature a single capacitance loop (a loop above the Z axis) with a hint of a second capacitance loop at lower frequencies. The low-frequency loop is more fully developed in 28% HC1 than in 15% HC1. Mass transport limitations are not evident except under extreme conditions, e.g. above 28% HC1 and 65 C. 

Surface Morphology. The initial Integrity of an adhesively bonded system depends on the surface oxide porosity and microscopic roughness features resulting from etching or anodization pretreatments. (17) The SAA surface characterized in this study consists of a thick (9 ym), porous columnar layer which provides excellent corrosion resistance in both humid and aggressive (i.e., Cl ) media. I The thinner FPL oxide provides a suitable substrate surface for evaluating the candidate inhibitors. 

In the 1960s organic phosphates (phosphonates) were introduced, such as ATMP and HEDP, which proved to be superior to phosphates in many ways, including their thermal stability and sequestering power. Although the corrosion inhibition of carbon steel, derived solely from phosphonates, remains a weak feature, this can be enhanced by syneigizing with other inhibitors, such as zinc. Like the polyacrylates, phosphonate chemistry has endured and remains a second basic DCA constituent of almost all modern formulations. 

Fouling is usually hindered by proper selection of materials of construction and the use of antifoulants and corrosion inhibitors. These mainly depend on the chemicals processed and are outside the scope of this text. Nonetheless, several design and operation features also help moderate reboiler fouling these are described below. 

Incidents of corrosion and fouling were only included if a feature unique to the column design, operation, or control contributed to their occurrence. For instance, tales of accelerated corrosion due to liquid maldistribution, or poor removal of water from a hydrocarbon column, constitute "columns that did not work. On the other hand, an incident where the wrong corrosion inhibitor was applied or a pH controller malfunctioned is related to handling the chemicals rather than to the column it would have occurred in any other piece of equipment processing the chemicals it therefore does not constitute a "column that did not work. ... 

A highly developed and reactive surface is another distinctive feature of polymer film materials. This feature only furnishes large potential in modification of films using various functional components, including Cl and numerous available technological procedures [3-6]. Corrosion inhibitors impregnated into a film may be found in different aggregate states. Despite considerable differences in physical and chemical parameters, films modified by Cl are able in most cases to retain their critical characteristics. 

Acetylenic compounds have long been known as effective corrosion inhibitors in hydrochloric acid. Tedeschi and coworkers (20,21) have presented over the past 10 years extensive investigations of these compounds. Their results are summarized in Tables 3,4 and 5. Some of the basic features of these comparisons are the position of the hydroxyl group and the position of the triple bond. Thus it appears that the hydroxyl group has to be in apposition to the acetylenic function and optimum efficiency is obtained if the acetylenic function is terminal. These two effects can be explained on the basis of the tautomerism shown in equation 18. 

Other field tests with proprietary vapour-phase inhibitors [17] in a parking garage with chloride-contaminated precast slabs did not show encouraging results. Corrosion-rate measurements showed a reduction of 60% in areas with initially intense corrosion but also an increase of corrosion rate in areas with low corrosion rates. On structures from 1960 with an admixed-chloride content higher than 1% by mass of cement, already featuring patch repairs, a three-year corrosion rate survey showed lower corrosion rates in the treated areas compared to untreated ones, but cracking and spalling increased also in the treated areas [18]. 

Features High temp, service, exc. resist, to steam/hot water, oil, gas, oils, amine corrosion inhibitors, bleach peroxide-cured FA100H is highest m.w. grade... 

Uses Pigment, corrosion inhibitor, tannin stain blocker, flame retardant, UV stabilizer for use In water- and solv.-based coatings stabilizer for metals and metal salts, esp. zinc, for formulation in zinc-rich coatings food-contact paper/paperboard Features Multifunction ... 

Uses Corrosion inhibitor for coatings based on acid side resins provides passivation effect to ferrous metal substrates Features Developed for stability in low pH formulations Properties Dk. amber liq., si. odor sp.gr. 1.28 g/ml pH 1-2 (5% aq.) Use Level 0.5-5%... 

Uses Corrosion inhibitor tor clear and pigmented coatings, aq. and soiv.-based coatings, high-solids coatings Features Contains no barium, chromium, or lead low ref. index low oil absorp. very small mean particle size Properties Off-wh. powd. 

Chem. Descrip. Benzotriazole (35%) in propylene glycol Uses Corrosion inhibitor tor aq. and hydrocarbon systems Features Good replacement tor Cobratec TT-351 if flammability is a concern... 

Features Multi-metal corrosion Inhibitor noncaustic nonflamm. Properties Amber liq. char, azole odor sol. 37% in water ( pH 10), 3.1% in water ( pH 1) sol. can be enhanced by use of polar cosoivs. such as ethylene glycol, propylene glycol, or IPA sp.gr. 1.128 pH neutral 89% min. act. 

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