Corrosion inhibitors and rust preventatives

Rust preventatives 

Our rust preventive additives provide excellent film forming performance. Solvent, oil, water-based additives and emulsions have been developed using our rust preventative range for dewatering fluids and for short, medium and long-term rust prevention.

The flexibility of our rust preventive additives allows for each component to be employed individually to impart rust prevention. Alternatively, they may be blended with waxes, resins, metal soaps, amines, over-based petroleum sulphonates or esters; to provide oils, soft greases or hard wax films. 

Our rust preventive range is soluble in a range of hydrocarbon solvents, green solvents, mineral oils, and esters and may be emulsified. Demulsification even in the presence of alkaline solutions is also available to the formulator.

Our products can be used in many applications, including: 

• Rust preventatives
• Dewatering fluids
• Greases
• Open gear and wire rope lubricants
• Hand applied compounds, pastes, fluids and aerosols
• Chain lubricants
• Mould release oils
• Metal forming. 

Use of our rust preventive additives can offer significant benefits to the formulator including: 

• Option of thin oil, soft grease or hard wax film
• Compatible with mineral oil, solvent and water-based systems
• Based on renewable resources
• Biodegradable
• Barium free
• Non-staining
• Easily removed by industrial cleaners. 

Food grade rust preventatives

Croda Inc announced that it is offering five products that have been registered as HX-1 ingredients for incidental food contact by NSF International. In order to gain NSF HX-1 approval, the lubricant manufacturer must prove that all ingredients in the formulation comply with 21 CFR. The program is generally accepted worldwide for the registration of incidental food contact lubricants.

The following products can serve as rust preventatives for food grade applications and have earned the NSF HX-1 registration:

• Tween™ 20 – nonionic surfactant, HLB 17
• Tween™ 40 – nonionic surfactant, HLB 16
• Tween™ 60 – nonionic surfactant, HLB 15
• Tween™ 80 – nonionic surfactant, HLB 15
• Tween™ 85 – nonionic surfactant, HLB 11.

All of these materials are ethoxylated sorbitan esters based on natural fatty acid. These products are effective at forming oil in water emulsions, particularly when used in combination with our Span™ range of non-ethoxylated precursors. Additionally, these products are all high HLB surfactants, which are inherently biodegradable and suitable for incidental food contact.

Corrosion inhibitors for oil (petroleum) production 

We can provide a wide range of corrosion inhibitors suitable for both aqueous and oil based systems.  

Corrosion inhibitors can be defined as chemical compounds that decrease the corrosion rate of a material, typically metal or alloy. Corrosion inhibitors are critical in water-based fluids because water accelerates the corrosion of metal. Corrosion can also be affected by the quality of the water, the formulation, the presence of multiple metals and other chemical compounds which may compete for the metal surface.

The corrosive effects of water in non-aqueous lubricants can be reduced with our range of water-insoluble and oil-soluble additives, both effective at low treat rates. Our oil-soluble additives are soluble in a wide range of base stocks including Group I, Group II and Group III mineral oils, PAO/esters and esters.

Corrosion inhibitors are surfactants which give them properties allowing them to partition between the oil and water phase. The hydrophilic group adsorbs onto the metal surface, which leaves the hydrophobic group to form a water resistant organic film on the surface. It is this film that prevents the corrosive species from coming into contact with the metal surface.

Types of corrosion inhibitors 

Water-soluble corrosion inhibitors are dosed continuously to maintain a steady concentration of inhibitor, avoiding any loss of production during injection. Oil-soluble corrosion inhibitors are successful in high velocity applications. The oil-soluble corrosion inhibitor formulation is passed between two pigs to obtain complete coverage of the internal surfaces of the pipe wall.

How can we help? 

Our superior corrosion inhibitor range offers a high level of protection against corrosion. Our offering includes both oil and water-soluble products as well as a range of dimer and trimer acids. Whilst dimer and trimer acids are not corrosion inhibitors in their own right, when added to imidazolines they form an oil-soluble salt which offers corrosion inhibition performance.