What to Specify When Buying Dimethyl Sulfate
Dimethyl sulfate (DMS, CAS 77-78-1) is quoted against a small number of specification parameters, and because the material is highly toxic the documentation and packaging are as important as the purity itself. This guide covers grades, typical specifications, packaging and transport, documentation, and safe handling. For the underlying chemistry, see the dimethyl sulfate technical overview.
Typical Specifications
Buyers normally specify assay, acidity, and appearance. A representative industrial specification is shown below.
| Parameter | Specification |
|---|---|
| Appearance | Clear and colorless liquid |
| Assay | 99.0% min |
| Acidity | 0.3% max |
| Molecular formula | C2H6O4S |
| Molecular weight | 126.13 g/mol |
Low acidity matters because the material hydrolyzes in the presence of water or alkali, forming sulfuric acid and methanol, which can affect both the reaction and the storage stability of the product.
Packaging and Transport
Dimethyl sulfate is a toxic, corrosive liquid and is shipped in packaging appropriate to its hazard classification (UN 1595, Class 6.1 with a corrosive subsidiary risk). Typical formats include steel drums or ISO tanks, always with the container tightly closed and clearly labelled. Confirm the packaging, closure type, and transport documentation with the supplier before shipment.
Documentation: COA and SDS
A serious supplier provides:
- A batch certificate of analysis (COA) reporting assay, acidity, and appearance.
- An up-to-date safety data sheet (SDS/MSDS) in the required format.
- Transport and regulatory documents as required for the destination country.
Because dimethyl sulfate is a hazardous material, always confirm the SDS and transport classification match your local requirements before ordering.
Safe Handling and Storage
Dimethyl sulfate must be handled in closed systems or fume hoods with local exhaust ventilation, using chemical-resistant gloves, eye protection, and protective clothing. It must be kept away from moisture, alkalis, and oxidants, stored cool and dry with the container tightly closed, and moved only with proper emergency response provisions in place.
Supplier Qualification Checklist
- Confirm whether the supplier manufactures or trades the material, and the country of origin.
- Check that the quoted grade and packaging match the COA you will receive.
- Confirm the supplier can provide consistent batches over time, not just a single lot.
- Verify lead time, shipping terms, and the ability to supply the required transport documentation.
Frequently Asked Questions
What purity of dimethyl sulfate is typical?
Industrial grades are commonly specified at 99.0% min assay, 0.3% max acidity, and clear and colorless appearance.
How is dimethyl sulfate packaged and shipped?
It is shipped as a toxic, corrosive liquid (UN 1595, Class 6.1) in drums or ISO tanks, with full transport documentation.
Does dimethyl sulfate come with a COA and SDS?
Yes. A batch COA covering assay, acidity, and appearance, plus an up-to-date SDS, should be supplied with the material.
Where can I buy dimethyl sulfate?
PolyBlueChem supplies dimethyl sulfate (CAS 77-78-1) with COA and MSDS. Contact our team for specifications, packaging, and a quotation.
References
- PubChem Compound Summary for dimethyl sulfate (CAS 77-78-1).
- Supplier specification sheets and transport classifications for dimethyl sulfate.
- Occupational safety guidance for toxic corrosive liquids.
Disclaimer: This article is provided for general informational purposes only and does not constitute technical, regulatory, or safety advice. Always refer to the current safety data sheet and applicable regulations before handling dimethyl sulfate.