EDDM — Non-Triazine H₂S Scavenger for Multiphase Systems
(Ethylenedioxy)dimethanol (EDDM, CAS 3586-55-8) is a non-triazine hydrogen sulfide scavenger that performs in multiphase produced fluids and pipelines. It reacts with H₂S at ambient temperature, forms no salt precipitates, stays non-corrosive to steel, and can be combined with corrosion-inhibitor packages for single-injection treatment.
Quick answer: EDDM removes H₂S via formaldehyde-donor chemistry — not a triazine ring. It scavenges in multiphase flow at ambient temperature, without salt precipitation, significant pH shift, catalyst poisoning or steel corrosion, and is compatible with corrosion-inhibitor formulations.
EDDM vs Triazine — H₂S Scavenging Behaviour
| Feature | EDDM (non-triazine) | Triazine scavengers |
|---|---|---|
| Reaction temperature | Ambient (exothermic) | Often needs elevated temperature |
| Salt / solid by-products | None — no salt precipitation | Can form solids (deposition risk) |
| pH impact | Neutral, minimal shift | Raises pH significantly |
| Steel corrosion | Non-corrosive | Can be corrosive |
| Catalyst interference | None | Can poison catalysts |
| Multiphase suitability | Yes — proven in multiphase fluids | Typically single-phase optimised |
Where EDDM H₂S Scavenging Fits
- Subsea and multiphase production pipelines (oil / water / gas)
- Crude oil desulfurization during production
- Natural gas sweetening at ambient temperature
- Produced-water and process-water H₂S control
- Refinery process streams requiring non-corrosive treatment
- Biogas desulphurisation
Related Reading
Frequently Asked Questions
What makes EDDM a non-triazine H2S scavenger?
EDDM (ethylenedioxy dimethanol, CAS 3586-55-8) removes hydrogen sulfide through a formaldehyde-donor chemistry rather than a triazine ring. It reacts selectively with H2S at ambient temperature in an exothermic reaction, without the salt precipitation, pH rise or catalyst poisoning associated with triazine-based scavengers.
Can EDDM scavenge H2S in multiphase flow?
Yes. EDDM has been shown to deliver H2S scavenging capacity in multiphase produced fluids — for example while transiting subsea production pipelines carrying oil, water and gas — making it suitable for scavenging during multiphase flow rather than only in a single phase. Its water miscibility helps it distribute through the aqueous phase where H2S partitions.
Does EDDM work alongside corrosion inhibitors?
EDDM chemistry can be combined with corrosion-inhibitor packages so that a single injection provides both H2S scavenging and corrosion protection, without deleteriously affecting the performance of the corrosion inhibitor or other production chemicals. Always qualify the specific blend for your system before field deployment.
Why choose EDDM over triazine for H2S removal?
EDDM operates at neutral to slightly acidic pH, produces no salt precipitates that can block pipelines, does not shift system pH significantly, is non-corrosive to steel, and does not interfere with downstream catalysts. Triazine scavengers can form solid by-products (e.g. dithiazine) that cause deposition and handling problems. See our comparison content for the full picture.
At what temperature does EDDM react with H2S?
EDDM reacts with H2S at room / ambient temperature. The desulfurization reaction is exothermic and generally requires no external energy input, which simplifies injection into produced fluids and pipelines.
Which EDDM grade is best for oilfield H2S scavenging?
The 92% and 95% grades are generally preferred for oilfield use because higher active content delivers more scavenging capacity per litre injected and lowers freight cost per kg of active. See the EDDM grades selection guide for details.
Evaluating a non-triazine H₂S scavenger?
Vasudev Chemo Pharma supplies EDDM (CAS 3586-55-8) to oil & gas operators and oilfield-chemical formulators worldwide — with technical support, batch COA, and export in FOB, CIF and DDP terms from Gujarat, India.