How to Read a Toluene Specification and CoA: Nitration Grade vs Industrial Grade

Summary. A toluene specification lists tests with limits. Our nitration-grade TDS (SPC-TDS-ARO-001) sets purity at 99.7% mass min and benzene at 0.05% mass max. Industrial and technical grades have only a typical assay of about 99.5% (GC) per SPC product data; the batch CoA, supplied with every delivery, carries measured values.

Why a toluene specification matters

Toluene (CAS 108-88-3, methylbenzene, toluol) looks the same in every drum: a clear, colourless liquid with a characteristic aromatic odour. What differs between grades is what you cannot see: how much of the liquid is toluene, how much is benzene or other hydrocarbons, and how much water it carries. A specification turns those invisible differences into numbers you can accept or reject.

Supreme Petro Chemicals, Chennai, is an importer and bulk distributor, not a manufacturer. That is exactly why the documents matter: you are buying against the maker’s published limits and a batch CoA, and the paperwork is how you check the match. The toluene product page carries the TDS and SDS downloads.

The nitration-grade specification, row by row

The only toluene TDS we hold is for nitration grade. It is the manufacturer’s published specification from the Kochi Refinery of Bharat Petroleum Corporation Limited, and the document number is SPC-TDS-ARO-001.

Source: manufacturer’s TDS, SPC-TDS-ARO-001, Rev 01.

What each test is there to protect (general knowledge, not part of the TDS):

• Purity: how much of the liquid is actually toluene.
• Colour: flags visible contamination or ageing.
• Relative density: a quick identity check that moves if the liquid is diluted or contaminated.
• Total sulphur: stated, not limited; it matters for sulphur-sensitive catalysts.
• Non-aromatics: carry-over changes solvency and reaction behaviour.
• Water: moisture hurts water-sensitive chemistry such as nitration.
• Benzene: benzene is a known human carcinogen. The TDS limits it to 0.05% mass max.
• Acid wash colour: in general, a pass/fail test for reactive impurities.

Two points are easy to miss. First, the TDS shows “Report” for total sulphur; as a general reading, that means the figure is stated on the certificate rather than limited, not a promise of a low value. Second, relative density here is measured at 15.56/15.56 °C, while the typical physical density we quote (0.867 g/cm3) is at 20 °C. Different conditions, different numbers: a CoA showing 0.870 at 15.56 °C is normal and does not conflict with 0.867 at 20 °C.

The industrial and technical figure: about 99.5% (GC)

For industrial and technical grades our product data gives a typical assay of about 99.5% by gas chromatography. That is a typical figure per SPC product data. No manufacturer TDS backs it on our file, so we do not attach it to the nitration TDS and we do not present it as a guaranteed limit; the batch CoA carries the measured values. If your process needs defined limits for benzene, water or non-aromatics in these grades, write them into your purchase requirement and check them on the CoA.

Technical grade is not food grade or pharma grade, and we do not list an AR, HPLC or ACS grade of toluene. If a specification sheet you receive claims otherwise, ask for the document that supports it.

Why one TDS covers one grade

A data sheet describes a product made to one specification. The nitration TDS therefore tells you nothing about the industrial or technical grade, even though all three are toluene with the same CAS number. The practical rules:

• Use the TDS limits to judge nitration-grade lots only.
• For other grades, agree limits in writing before the order.
• Always ask which grade a quoted figure belongs to.

How to check a batch CoA, step by step

1. Match the grade and batch. The CoA should name the product and grade you ordered and carry a batch reference you can trace to the delivery.
2. Compare purity. Nitration grade should show 99.7% mass or higher. Ask which method was used; gas chromatography is the usual one for purity.
3. Check benzene. For nitration grade it must be 0.05% mass or lower. This is the line most buyers with a regulatory duty look at first.
4. Check water. 500 ppm max for nitration grade. A moisture result well above this is a reason to hold the lot.
5. Check non-aromatics and colour. 0.30% mass max and 20 Pt-Co max respectively.
6. Check relative density and acid wash colour. Density should sit in 0.869 to 0.873 at 15.56/15.56 °C; acid wash colour should pass with 2.
7. Look for the units. Percent by mass and percent by volume are not interchangeable, and ppm is not percent.

Common reading mistakes

• Mixing conditions. Comparing a 20 °C density with a 15.56 °C relative density.
• Using the wrong grade’s limits. Judging an industrial lot against the nitration TDS, or the reverse.
• Reading “min” as the typical value. 99.7% min means 99.7% or higher, and the real value is on the CoA.
• Assuming a name implies a grade. Methylbenzene, toluol and toluene are one chemical; the name does not state purity.
• Skipping the SDS. The CoA says what is in the lot; the SDS tells you how to handle it. Both matter.

Standards and the BIS question

We do not claim BIS-marked supply for any grade. The nitration TDS describes the manufacturer’s Kochi Refinery as having a BIS-licensed Quality Control Laboratory and quotes the manufacturer’s published specification. If your quality system needs a named standard on the CoA, state it in your enquiry so we can confirm what documentation exists before you order.

What to send us when you enquire

To get a useful quote, give us the grade, the quantity, the pack you want (our product data lists 200 L barrels, 1000 L IBC tanks and bulk road tankers; the pack is confirmed per enquiry), the delivery location in South India and the documents you need. We quote within 4 working hours. Ask for the TDS, the SDS and the batch CoA, which is supplied with every delivery. For choosing between aromatic solvents read Toluene vs Mixed Xylene, and for the supply side see our Chennai toluene supplier guide.

Bottom line

A toluene specification is only useful if you read it against the right grade, under the right conditions, with the batch CoA in hand. Nitration grade has a manufacturer’s TDS with hard limits. Industrial and technical grades are described by a typical assay of about 99.5% (GC) per SPC product data; the batch CoA carries the measured values, and if it matters to your process, write your limits into your purchase requirement.