Why do some petroleum products have a buttery yellow hue, and how do refining companies instantly identify a specific grade of fuel? Odds are that you, or someone you know, has been in touch with Yellow 107. This solvent yellow dye also commonly contributes to the color of drums, tanks, and lines used for wax processing and in lubricant manufacturing.
If you’re interested in learning more about yellow 107, then this comprehensive guide is for you. Here we’ll look at the history of yellow 107, its chemical structure and performance characteristics, its use as a dye additive for lubricant and other petroleum processing operations, and how the best yellow dye stacks up against the competition.
What Exactly Is Yellow 107?
Yellow 107 is the synthetic dye more commonly referred to by its color index identity of C.I. Solvent Yellow 107 (CAS number 67990-27-6, C.I. number 21140). The chemical formula for Yellow 107 is C44H62N4O2, and its molecular weight is 674.96 g/mol. Yellow 107 is produced by double diazotisation of 3,3-dimethylbenzidine, coupled with 4-nonylphenol.
Warm yellow with an orange-yellow hue. Dissolves completely in hydrocarbons and petroleum products and non-polar media with no difficulty or cloudiness. 100% Oil Soluble—100% soluble in hydrocarbons, petroleum products, and non-polar media. Available as a concentrated liquid in high-flash solvents, xylene or toluene.
Apart from its intense tinting strength, the highly significant property that makes Yellow 107 extremely useful is that it is compatible with a large number of petroleum products and is thermostable. It does not change the properties or qualities of the fuels or oils that it colors – just what the industry wants.
Primary Applications of Yellow 107
1. Fuel and Petroleum Product Colour-Coding
Most of the Yellow 107 produced is used in the petroleum industry. Fuel refineries and fuel distribution companies use it to differentiate between different ranges and types of fuel, for example, through sulfur content in diesel, high-octane and low-octane fuels, and between unleaded and leaded petrol. This cosmetic difference isn’t just cosmetic; it’s about preventing miscommunication and protecting consumers on the road and in the tank.
Different countries have different requirements for colour and concentration of these fuel types. Fuel identification programmes rely on the dye colour, which is commonly used in Asia, Africa, and the Middle East to identify fuel. It is one of the main dyes approved for petroleum colouring in India and beyond.
2. Lubricants, Greases, and Industrial Oils
Manufacturers of transmission fluids, gear oils, hydraulic oils and industrial lubricants use Yellow 107, as it gives uniform, recognizable coloration to the end product to allow consumers to readily identify it. The product also differentiates the manufacturer’s product in the market.
3. Wax, Candle, and Speciality Product Colouring
Yellow 107 is freely soluble in paraffin and other wax vehicles, making it a popular bright, stable yellow for candles and wax products where high tinting strength is required. It is highly soluble, so there is no sediment, blockages in wicks, or uneven colour distribution.
4. Printing Inks and Coatings
It is also used in printing inks, in which it exhibits high tinting strength in addition to being readily dispersed throughout the ink.
Case Study: Standardising Fuel Colour-Coding for an Indian Petroleum Distributor
Background: The distributor, which was a mid-size distributor in the petroleum business, with a depot network around western India, faced higher rejection at the pump due to problems with the identification of fuel. All the depots used dyes from various local sources, and the colour used in the same grade of the fuel varied across depots. The fuel sample was submitted for analysis and inspection.
The Issue: The inconsistency was confusing to the depot workers and even suggested that the product was being altered by the customer. The distributor was after a predictable yellow dye so that consistency would be achieved at every site without changing over to a new mixing system.
The Result: The distributor worked with the supplier to continue to source their yellow dye supply from a single ISO-certified Yellow 107 (CAS 67990-27-6) supplier in a high-flash solvent base. The standard flash formulation was pre-calibrated for 15 ppm and supplied in a ready-to-use liquid formulation that could be injected in-line directly into fuel lines without further dilution.
Key Learning: Moving to a quality-assured, single-source Yellow 107 supplier saved the headaches associated with inconsistent dye batches. This experience speaks to an important lesson that applies to all dye markets in the petroleum industry: supplier consistency is a critical factor.
What to Look for When Sourcing Yellow 107
Because Yellow 107 is a commercial dye and not a single pure compound (the alkylation and coupling process produces a mixture of related structures), quality can vary significantly between manufacturers. Here are the factors that matter most:
- Pure: The product must be free of all insoluble matter. Minute quantities of insoluble matter can build up in storage and fuel injection systems after time.
- Fully dissolvable: Yellow 107 should fully dissolve in the products that it is added to, such as oil or fuel, and result in a homogeneous, transparent colour without any cloudiness.
- Consistent: If you go with a product that is subject to spectrophotometric quality assurance on each batch, then you will have consistency of intensity of colour as well as colour hue.
- Wide range of solvent bases: Whether you want Yellow 107 to be used in a high-flash solvent, xylene, or toluene base, a competent manufacturer will be able to provide you with all three.
- ISO certification: ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 certifications prove a company’s dedication to quality, environment, and safety standards.
Anar Chemicals LLP are that committed to consistency; they are ISO 9001:2015, ISO 14001:2015 & ISO 45001:2018 accredited with over 40 years of experience in dyes and speciality chemicals. They manufacture Yellow 107 in both high-flash and xylene or toluene solvent bases, and their liquids are supplied to fuel and petroleum companies around the world. View our full range of liquid petroleum or fuel dyes.
Frequently Asked Questions About Yellow 107
What is Yellow 107?
Yellow 107 (Solvent Yellow 107, CAS 67990-27-6) is a yellow colour, mainly used in the colouring and distinction of fuels, lubricants, and other oils. It can be used in wax colouring, candle making, printing inks, and in specific plastic products.
What is the CAS number for Yellow 107?
CAS 67990-27-6 Colour Index Number C.I. 21140.
Are Solvent Yellow 124 and Yellow 107 the same?
No. Solvent Yellow 124 and Yellow 107 are both dyes with different chemical structures and purposes. Solvent Yellow 124 was the dye of the EU Euromarker used for the identification of tax-exempt fuel and to colour fuel; Yellow 107 is used as a colourant for visually identifying fuel to colour code for the fuel industry.
How much Yellow 107 should I add to fuel?
The typical application rate of Yellow 107 in petroleum products is between 10 and 20 ppm, with the exact amount being dependent on the intensity of the colour required and the particular product being coloured.
Is Solvent Yellow 107 reactive?
No. Solvent Yellow 107 is non-reactive in all hydrocarbon systems at colouring levels and does not affect combustion qualities, octane or cetane values, or the mechanical performance of any engines.
How should Yellow 107 be stored?
Storage conditions: Store in a tightly closed container in a dry and well-ventilated environment at a temperature range of 5 °C to 40°C. Shelf life: 2 years from the date of manufacture at room temperature.
Where can I buy high-quality Yellow 107?
Yellow 107 is sold by speciality chemical vendors such as Anar Chemicals LLP (anarchem.com), an ISO certified company with more than 40 years of experience in manufacturing petroleum dyes and specialty chemicals. The company has manufacturing of Yellow 107 with high-flash, xylene, and toluene solvent base.
Is Yellow 107 safe to handle?
As with the majority of industrial solvent dyes, this product must be handled using normal precautions—suitable gloves, eye protection, and exhaust ventilation. Use the manufacturer’s SDS/MSDS for details of safety precautions.