Industrial methylating agent
Di Methyl Sulfate (DMS) Supplier & Distributor in India & Worldwide
Chelora Agrochem is a trusted Di Methyl Sulfate (DMS) supplier and distributor in India, connecting buyers with high-purity material sourced from leading, quality-approved manufacturers. Our dimethyl sulfate meets 99.5% min purity with low acidity and moisture, full documentation and reliable bulk supply across India and to buyers worldwide.
As a specialised distributor of chemical products, we do not manufacture in-house — instead we source only from reliable, audited manufacturers, giving you dependable material, competitive pricing and a single point of contact for all your DMS requirements, backed by COA, MSDS and TDS on every order.
- CAS number
- 77-78-1
- Formula
- (CH3)2SO4
- Molecular weight
- 126.13 g/mol
- Purity
- 99.5% min
Quick product specifications
Di Methyl Sulfate at a glance
Identifiers, physical data and trade codes for DMS. Batch-specific figures are confirmed on the Certificate of Analysis supplied with each consignment, in India and on export shipments alike.
- Chemical name
- Di Methyl Sulfate
- CAS number
- 77-78-1
- Molecular formula
- (CH3)2SO4
- Molecular weight
- 126.13 g/mol
- IUPAC name
- Dimethyl sulfate
- EC number
- 201-058-1
- HS code
- 2920 90National subheading as per destination
- UN number
- UN 1595Dimethyl sulphate · Class 6.1 with subsidiary risk 8, packing group I
- Appearance
- Colourless to pale yellow oily liquidFaint onion-like odour — far too weak to serve as a warning of exposure
- Melting point
- About −32 °C
- Boiling point
- About 188 °C
- Density
- About 1.33 g/cm³Liquid, 20 °C
- Flash point
- About 83 °CClosed cup, combustible liquid
- Solubility
- Reacts slowly with waterHydrolyses to methanol and sulphuric acid; miscible with acetone, ethers and aromatic solvents
- Purity
- 99.5% min
- Synonyms
- DMSDimethyl sulphate · Methyl sulfate · Sulfuric acid dimethyl ester
- Product form
- Bulk liquid
- Documentation
- COA, MSDS & TDSSupplied with every order
Product overview
What is Di Methyl Sulfate?
Di Methyl Sulfate (DMS) is the industrial methylating agent of choice — the cheapest and most reactive way to put a methyl group onto a phenol, an amine or a thiol at scale. It is also one of the most hazardous reagents in routine commercial use, and should only be handled by plants set up for it.
With the formula (CH3)2SO4 (CAS 77-78-1), DMS is a colourless to pale yellow oily liquid boiling at about 188 °C with decomposition, freezing near −32 °C and with a density of roughly 1.33 g/cm³. It reacts slowly with water, hydrolysing to methanol and sulphuric acid, which is also the basis of the standard quench procedure.
Its faint onion-like odour is often described as a warning property, but it is not one: the odour threshold sits well above the level at which damage occurs, and the symptoms of inhalation are typically delayed for several hours. Any plant using DMS needs closed handling, trained operators and an emergency plan written before the first drum arrives.
How it is made
Dimethyl sulfate is made commercially by the continuous reaction of dimethyl ether with sulphur trioxide. The crude product is stabilised and purified by distillation under reduced pressure to strip residual acidity and methyl hydrogen sulfate, then packed dry under nitrogen.
What that means for your process
- 99.5% min assay for predictable methyl transfer stoichiometry
- Low free acidity, which otherwise catalyses hydrolysis in storage
- Low moisture — water converts the reagent to methanol and sulphuric acid
- Nitrogen-blanketed, dedicated packing with full dangerous-goods documentation
Applications
What is Di Methyl Sulfate used for?
DMS is used as a reagent rather than as a component of a finished product. Its main applications, industry by industry, include:
Dyes, pigments & agrochemicals
O-methylation of phenols is the single largest use.
- Phenols to anisoles and aryl methyl ethers
- Methylation of 3,6-dichlorosalicylic acid to dicamba
- Methylated azo and anthraquinone dye intermediates
Pharmaceuticals & fine chemicals
N-, O- and S-methylation of APIs and their intermediates.
- N-methylation of amines and heterocycles
- S-methylation of thiols and thioethers
- Methyl esters and ethers in API synthesis
Surfactants & quaternaries
Exhaustive methylation of tertiary amines gives quaternary ammonium salts.
- Quaternary ammonium surfactants
- Fabric softeners and antistatic agents
- Cationic polymer and emulsifier intermediates
Process route
How does methylation with DMS work?
The substrate is first converted to its anion with a base — a phenolate, an amide or a thiolate — which then attacks one of the two methyl groups on the sulfate. Only the first methyl transfers readily; the methyl hydrogen sulfate left behind is far less reactive, which is both an economy and a safety consideration in process design.
Di Methyl Sulfate
Metered in under closed conditions. Assay and acidity decide conversion and by-product load.
(CH3)2SO4Substrate activation
The phenol, amine or thiol is deprotonated with caustic or carbonate.
BaseMethyl transfer
One methyl group transfers to the anion; methyl hydrogen sulfate is the by-product.
Methyl transferMethylated product
Anisoles, N-methyl amines, quaternaries or actives such as dicamba; excess reagent is quenched.
Methyl etherIn depth
Di Methyl Sulfate applications by industry
Below is a detailed breakdown of where DMS is used and the role it plays in each downstream product.
| Industry | Typical downstream products | Role of DMS |
|---|---|---|
| Dyes & pigments | Methylated azo and anthraquinone intermediates | Methylating agent |
| Agrochemicals | Dicamba and other methylated actives | Methylating agent |
| Pharmaceuticals | N-, O- and S-methylated API intermediates | Reagent |
| Surfactants | Quaternary ammonium salts, fabric softeners | Quaternising agent |
| Fine chemicals | Aryl methyl ethers and methyl esters | Reagent |
Safety
Is Di Methyl Sulfate hazardous?
Yes — DMS is among the most hazardous reagents in common industrial use. It is fatal if inhaled, toxic if swallowed, causes severe skin burns and eye damage, may cause an allergic skin reaction, is suspected of causing genetic defects and may cause cancer. Critically, the symptoms of inhalation are usually delayed by several hours, so an exposed person can feel fine while serious lung injury develops.
DMS should be handled only in closed systems, with metered transfer, local exhaust ventilation and gas detection, by operators trained specifically for it. Store it in sealed, nitrogen-blanketed drums in a cool, dry, ventilated and bunded area, away from moisture, strong bases, ammonia, amines and oxidisers. Full PPE means chemical-resistant gloves and suit, goggles and face shield, with supplied-air respiratory protection available for any open handling or spill response. Anyone with suspected exposure must be placed under medical observation even if they have no symptoms. Excess reagent is destroyed by controlled hydrolysis with dilute alkali. A full MSDS is supplied with every order.
Signal word: Danger
Fatal if inhaled · toxic if swallowed · causes severe skin burns and eye damage · suspected mutagen · may cause cancer · symptoms of exposure are typically delayed for hours
Safe-handling essentials
- Closed, metered transfer only — never open pouring or manual decanting
- Local exhaust ventilation and gas detection at every handling point
- Supplied-air respiratory protection available for spill response
- Chemical-resistant suit and gloves, goggles and face shield
- Do not rely on odour as a warning — the threshold is above the harmful level
- Place anyone with suspected exposure under medical observation, symptoms or not
- Quench excess reagent by controlled hydrolysis with dilute alkali
- Store sealed and nitrogen-blanketed, away from moisture, bases, ammonia and amines
- Transport as UN 1595, class 6.1 with subsidiary risk 8, packing group I
Grades
Di Methyl Sulfate grades & technical specifications
We supply DMS in standard industrial grade and in tightened low-acidity, low-moisture grades for pharmaceutical and fine chemical work.
| Parameter | Specification |
|---|---|
| Assay (purity) | 99.5% min |
| Appearance | Colourless to pale yellow oily liquid |
| Acidity (as H2SO4) | 0.1% max |
| Methyl hydrogen sulfate | 0.3% max |
| Moisture | 0.05% max |
| Colour (APHA / Hazen) | 30 max |
| Non-volatile matter | 0.02% max |
| Product form | Bulk liquid |
Note: Values are representative. Batch-specific figures are provided on the Certificate of Analysis (COA) supplied with each consignment.
Supply
Packaging, MOQ & supply
From trial quantities for process validation to repeat container loads on contract — packed, documented and dispatched to your plant in India or overseas.
Packaging
250 kg lined mild-steel or HDPE drums under a nitrogen blanket, and bulk in dedicated ISO tank containers for large users.
Minimum order quantity
Flexible — single drums for process validation through to tank-container loads.
Shelf life
Good shelf life in sealed, unopened drums stored cool, dry, nitrogen-blanketed and away from moisture.
Dispatch
Pan-India dispatch and worldwide export with complete dangerous-goods documentation and logistics support.
Why buy from us
Why choose Chelora as your DMS supplier?
As an established Di Methyl Sulfate supplier and distributor based in India and shipping worldwide, we work with a wide network of trusted manufacturers to combine consistent quality with dependable service. More about Chelora Agrochem.
High purity, every batch
99.5% min assay, sourced only from quality-approved manufacturers we have worked with and audited.
Full documentation
COA, MSDS and TDS travel with every order, so your QA and EHS teams are never chasing paperwork.
Reliable bulk supply, flexible MOQ
Single packs for process trials through to repeat container loads on schedule.
Worldwide supply
Export-grade packing, dangerous-goods documentation and on-time dispatch to plants across Asia, the Middle East, Europe, Africa and the Americas.
Technical & safe-handling support
Guidance on closed handling, quench and destruction procedures, PPE and emergency planning from a team that knows this is not an ordinary reagent.
One point of contact
Source DMS alongside your other intermediates — one enquiry, one team, one invoice.
Ordering
How to order Di Methyl Sulfate from Chelora
Ordering is simple and fast — most enquiries are answered with pricing and availability within 24 hours.
- 1
Send your enquiry
Tell us the grade, quantity and application you are buying for.
- 2
Receive a quotation
We send pricing along with the COA and MSDS for your review.
- 3
Request a sample
Test suitability for your process before you commit to a bulk order.
- 4
Confirm the order
Lock in quantity, packaging and delivery preference.
- 5
Dispatch & tracking
We dispatch with full documentation and keep you updated until delivery.
Documentation
Di Methyl Sulfate MSDS & COA
A summary of key safety information and a representative Certificate of Analysis. The complete 16-section Safety Data Sheet and the actual batch COA are supplied with each shipment — and both are sent with your quotation when you ask for a quote.
Safety data summary (MSDS)
| Section | Details |
|---|---|
| Hazard classification | Acute toxicity cat. 2 (inhalation); acute toxicity cat. 3 (oral); skin corrosion cat. 1B; serious eye damage cat. 1; skin sensitisation cat. 1; germ cell mutagenicity cat. 2; carcinogenicity cat. 1B; STOT SE cat. 3 |
| Signal word | Danger |
| First aid — inhalation | Move to fresh air at once; keep at rest and warm; get immediate medical attention and insist on observation — effects are delayed |
| First aid — skin | Remove contaminated clothing under a shower; flush with copious water for at least 15 minutes; get immediate medical attention |
| First aid — eyes | Rinse immediately with running water for at least 15 minutes; get immediate medical attention |
| Handling | Closed, metered systems only; LEV and gas detection; supplied-air protection for spill response |
| Storage | Cool, dry, sealed, nitrogen-blanketed and bunded; away from moisture, bases, ammonia & amines |
| Environment | Prevent release to drains, soil and waterways; hydrolyse residues with dilute alkali |
| Transport | UN 1595; class 6.1 with subsidiary risk 8; packing group I |
Certificate of Analysis (representative)
| Test parameter | Specification | Method |
|---|---|---|
| Assay (purity) | 99.5% min | GC |
| Appearance | Colourless to pale yellow liquid | Visual |
| Acidity (as H2SO4) | 0.1% max | Titrimetric |
| Moisture | 0.05% max | Karl Fischer |
| Colour (APHA) | 30 max | Comparator |
| Non-volatile matter | 0.02% max | Gravimetric |
The actual batch COA is supplied with each shipment.
FAQ
Frequently asked questions
Common questions from buyers specifying DMS for dye, agrochemical, pharmaceutical and surfactant manufacture.
What is Di Methyl Sulfate used for?
DMS is the standard industrial methylating agent. It is used to convert phenols into aryl methyl ethers for dye, pigment and agrochemical intermediates, to N-methylate amines and heterocycles in pharmaceutical synthesis, to S-methylate thiols, and to quaternise tertiary amines into the quaternary ammonium salts used in surfactants and fabric softeners.
What is the CAS number of DMS?
The CAS number is 77-78-1 and the molecular formula is (CH3)2SO4, with a molecular weight of 126.13 g/mol. Its EC number is 201-058-1 and the IUPAC name is dimethyl sulfate.
How is Di Methyl Sulfate made?
Commercially it is made by the continuous reaction of dimethyl ether with sulphur trioxide. The crude product is then purified by distillation under reduced pressure to strip residual acidity and methyl hydrogen sulfate, and packed dry under nitrogen.
Is Di Methyl Sulfate hazardous?
Yes — it is one of the most hazardous reagents in routine industrial use. It is fatal if inhaled, toxic if swallowed, causes severe skin burns and eye damage, is a suspected mutagen and may cause cancer. It should only be handled in closed, metered systems by operators trained for it; we supply a full MSDS with every order.
Why are the symptoms of DMS exposure delayed?
DMS causes little immediate irritation, so an exposed person often notices nothing at the time. The damage to the airways and lungs develops over the following hours, and can become serious long after exposure ended. This is why the faint onion-like odour must never be treated as a warning property, and why anyone with suspected exposure is placed under medical observation whether or not they feel unwell.
How should DMS be stored and how is excess destroyed?
Store it in sealed, nitrogen-blanketed drums in a cool, dry, ventilated and bunded area, away from moisture, strong bases, ammonia, amines and oxidisers. Excess reagent and residues are destroyed by controlled hydrolysis with dilute alkali, which converts the DMS into methanol and sulphate salts.
Do you provide COA and MSDS for DMS?
Yes, we provide a batch-specific COA and MSDS with every order, along with the dangerous-goods documentation the packing group I classification requires.
Do you supply and export Di Methyl Sulfate?
Yes, we supply DMS across India and export internationally with complete dangerous-goods documentation, sourced from reliable manufacturers.
Request a quote or sample
Need a reliable DMS supplier?
Looking for a dependable Di Methyl Sulfate (DMS) supplier and distributor — in India or anywhere we export to? Tell us the grade and quantity you need — our team responds with competitive bulk pricing, samples and complete documentation (COA, MSDS, TDS) within 24 hours.
Or email source@cheloraagrochem.com