Summary. Two quotes for mineral turpentine can look different without either being wrong. One may show a limit and the other a typical value, the flash points may come from different test methods, and the distillation cuts may differ. Line up the standard and edition, the distillation window, the flash-point method, the aromatics limit and the batch Certificate of Analysis before you compare price or product name.
Ask three suppliers for mineral turpentine and you may get three sheets with different boiling ranges, flash points and registry numbers. That is not always a sign that one of them is wrong. This guide is about one job: comparing two MTO quotes or data sheets fairly, as a buyer. What MTO is, its other names, identifiers and our own IS 1745:2018 limits are on the identity table and the specification table of the product page; this guide does not repeat them, it shows you how to use that kind of information when two sheets disagree. For sourcing background, see MTO supplier in Chennai.
Why two sheets for the same name disagree
General knowledge: names such as mineral turpentine, mineral spirits and white spirit are regional habits, not definitions, so two products with the same name can be different cuts and two products with different names can be the same cut. Four things cause most of the confusion.
- The registry number. MTO is a mixture, so sheets cite the registry number of the petroleum stream they believe describes the product, and different suppliers cite different ones. Put the full product name on the order and check that the name agrees across the quote, certificate and safety data sheet.
- Limit versus typical value. A specification sets a limit that every lot must meet. A safety data sheet usually gives a typical figure that is indicative. A limit and a typical value answer different questions and should never sit in the same column of your comparison.
- Test method. Abel is itself a closed-cup method, but other closed-cup methods do not give identical results on the same sample, and some sheets state no method at all. Two flash points are comparable only if the method matches. If a sheet gives a number with no method, treat it as unverified for comparison.
- Distillation cut. Sheets sold under one name can describe different cuts. A sheet quoting a narrower initial-to-final boiling window describes a narrower cut, which in general means more uniform evaporation.
The comparison method, step by step
- Ask each supplier for the technical data sheet and note the standard named, including the edition year. A different edition can carry different limits.
- For every figure, mark whether it is a limit, a typical value or merely reported. Only limits are commitments.
- Compare the initial and final boiling points as a pair, not just the product name.
- Compare the flash-point value together with the method used to measure it.
- Compare the aromatics limit. A ceiling such as 40% (V) maximum is not a low-aromatic grade; low-aromatic or odourless material is a different product with a different sheet.
- Compare colour and residue on evaporation if cleanliness of the cut matters to your process.
- Ask for the batch Certificate of Analysis and read it against the data sheet (below).
- Check that the product name and registry number agree across the quote, certificate and safety data sheet, and that the document set matches the maker you were told about.
| Check | Why it matters |
|---|---|
| Limit or typical value? | A limit is a requirement; a typical value is indicative |
| Which flash-point method? | Different methods give different results; an unnamed method cannot be compared |
| What distillation window? | Describes the cut and, in general, how fast the solvent evaporates |
| What aromatics limit? | Relates to solvent power and odour |
| Which standard edition? | Limits can change between editions |
| Is there a batch certificate? | Confirms the results for the lot you receive, not a typical product |
A worked reading example
The two sheets below are an illustration only. They are not real suppliers and the numbers are not SPC figures.
| Item | Sheet A | Sheet B |
|---|---|---|
| Flash point | 35 °C minimum, method named | Approx. 40 °C, no method |
| Distillation | IBP 140 °C min, FBP 200 °C max | Boiling approx. 150 to 200 °C |
| Aromatics | 25% (V) maximum | Not stated |
A quick reading would say Sheet B has the higher flash point and a tighter cut, so it is the better product. A careful reading says the opposite is possible. Sheet A states commitments: a limit with a named method, a distillation window with both ends bounded and an aromatics ceiling. Sheet B states a typical flash point with no method, a typical range rather than a bounded window, and says nothing about aromatics. You cannot tell from Sheet B what the lot will be allowed to measure. The fair comparison is to ask Supplier B for a data sheet with limits and a named method, and to compare only like with like. If Supplier B cannot provide one, the comparison is between a specified product and an unspecified one.
Reading a certificate against a data sheet
General knowledge: a data sheet tells you what a supplier is prepared to guarantee, and a certificate of analysis tells you what a particular lot measured. Put each certificate next to the data sheet it claims to meet and run through these steps.
- Every parameter named on the data sheet should appear on the certificate. A certificate that omits the flash point, the distillation points or the aromatics figure is telling you less than the sheet promised.
- Every measured value should sit inside the limit, not merely near it.
- The test methods named on the certificate should match those on the data sheet. A different method on the certificate is a reason to ask a question before accepting the lot.
- Units should match. A certificate in different units from the sheet needs a conversion you can check yourself.
- The standard and its edition year on the certificate should match the quote.
- The batch or lot number should match the consignment, and the product name should match the order.
Parameters reported rather than limited, such as 50% and 95% recovery or density on some sheets, cannot pass or fail; they tell you where the lot sits. Keep them and compare them lot to lot, so you notice drift before it affects your product.
Questions to put to every supplier
- Which standard and edition does the product meet, and can you send the data sheet?
- Which maker or refinery does the lot come from, and does the certificate cover that maker?
- Which method is used for the flash point?
- What are the initial and final boiling points as limits?
- What is the aromatics limit, and is the material a standard or a low-aromatic grade?
- Will a batch Certificate of Analysis accompany every delivery?
We supply technical grade MTO as an importer and bulk distributor in Chennai, with the data sheet, the safety data sheet and a batch Certificate of Analysis with every delivery, and we quote within 4 working hours. For what applies to our own MTO, see the Mineral Turpentine Oil (MTO) product page, and to send an enquiry use the contact page. If you are working with terpene-type products rather than petroleum solvents, our pine oil and di-pentene pages describe those separately; for aromatic thinners see toluene and mixed xylene.