Sodium Thiosulfate (25%) vs EPDM Compatibility
Verified chemical resistance rating (Safe for Continuous Industrial Service), thermal boundary limits (Ambient to elevated operating temperatures within standard material limits), and material specification guide for EPDM exposed to Sodium Thiosulfate (25%) in Inorganic Salt / Brine / Ionic Solution service.
Sodium Thiosulfate (25%) vs EPDM: A-Excellent
Exposing EPDM to Sodium Thiosulfate (25%) (Formula: Na2S2O3 (25% aq.), CAS: 7772-98-7) carries an official rating of A-Excellent (Safe for Continuous Industrial Service). Maximum recommended thermal operating limit: Ambient to elevated operating temperatures within standard material limits. Best Grade A alternative materials for continuous or high-temperature service: Polypropylene, Stainless Steel, Viton, PTFE.
Technical Specifications and Operating Parameters
| Chemical Medium | Sodium Thiosulfate (25%) |
|---|---|
| Chemical Formula | Na2S2O3 (25% aq.) |
| CAS Registry Number | 7772-98-7 |
| Chemical Functional Class | Inorganic Salt / Brine / Ionic Solution |
| Wetted Material | EPDM |
| Official Resistance Rating | A-Excellent (Grade A) |
| Engineering Service Verdict | Safe for Continuous Industrial Service |
| Max Temp and Concentration Limit | Ambient to elevated operating temperatures within standard material limits |
| Best Grade A Alternatives | Polypropylene, Stainless Steel, Viton, PTFE |
| Backtest and Audit Verification | Verified against Cole-Parmer, ISM, Graco & CP Lab Safety industrial chemical resistance charts. |
Sodium Thiosulfate (25%) Cross-Material Comparison Matrix (9 Materials)
Direct benchmark ratings across all 9 reference industrial materials for Sodium Thiosulfate (25%):
| Material Name | Compatibility Rating | Service Verdict | Temperature Limit | Datasheet |
|---|---|---|---|---|
| Buna-N | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| EPDM | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| HDPE | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| Polypropylene | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| PTFE | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| PVC | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| PVDF | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| Stainless Steel | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
| Viton | A-Excellent | Safe for Continuous Industrial Service | Ambient to elevated operating temperatures within standard material limits | Report |
Chemical and Material Interaction Analysis
Engineering Compatibility Verdict
Sodium Thiosulfate (25%) vs EPDM: A – Excellent (Fully Compatible)
Summary Verdict: EPDM (Ethylene Propylene Diene Monomer) is rated A-Excellent (Safe for Continuous Industrial Service) when exposed to Sodium Thiosulfate (25%) (Formula: Na2S2O3 (25% aq.), CAS: 7772-98-7). Approved for continuous fluid handling, bulk storage, valves, and sealing assemblies.
Quick Engineering Specifications
| Chemical Media | Sodium Thiosulfate (25%) |
|---|---|
| Chemical Formula | Na2S2O3 (25% aq.) |
| CAS Registry Number | 7772-98-7 |
| Chemical Classification | Inorganic Salt / Brine / Ionic Solution |
| Wetted Material | EPDM (Ethylene Propylene Diene Monomer) (Synthetic Polar-Service Elastomer) |
| Official Resistance Rating | A – Excellent (Fully Compatible) (Grade A) |
| Recommended Temperature Window | Ambient to elevated operating temperatures within standard material limits (Material limit: -60°F to 300°F (-51°C to 149°C)) |
| Top Grade-A Alternatives | Polypropylene, Stainless Steel, Viton, PTFE |
| Data Verification Status | Verified against Cole-Parmer, ISM, Graco & CP Lab Safety industrial chemical resistance charts. |
Chemical & Material Interaction Analysis
Sodium Thiosulfate (25%) is classified as an inorganic salt / brine / ionic solution (electrolytic corrosion risk in metals, especially chlorides/halides, while thermoplastics remain largely inert). Used in water treatment, chemical dosing, brine handling, and industrial process streams. When selecting wetted components for EPDM, engineers must account for both concentration-dependent chemical attack and thermal stress:
- Reaction & Failure Mechanism: Chemically inert interface with no measurable corrosion, polymer chain scission, or elastomeric swell under standard operating conditions.
- Material Profile (EPDM): Outstanding resistance to polar fluids including ketones (acetone, MEK), alcohols, glycols, phosphate ester hydraulic fluids (Skydrol), alkalis, and dilute acids. However, exhibits rapid, catastrophic volumetric swelling and softening when exposed to petroleum oils, gasoline, diesel, kerosene, aliphatic/aromatic hydrocarbons, and chlorinated solvents.
- Application Scope: Common wetted components include butterfly valve liners, O-rings, sanitary Tri-Clamp gaskets, caustic dosing hoses, and water/wastewater treatment seals.
Cross-Material Compatibility Comparison for Sodium Thiosulfate (25%)
To help you select the longest-lasting piping, valve lining, or O-ring seal for Sodium Thiosulfate (25%), the table below compares EPDM against 8 other common industrial engineering materials:
| Wetted Material | Compatibility Rating | Service Recommendation | Material Temp Range |
|---|---|---|---|
| Polypropylene (PP Homopolymer & Copolymer) | A-Excellent | Safe for Continuous Industrial Service | 32°F to 180°F (0°C to 82°C) |
| 316 / 304 Austenitic Stainless Steel | A-Excellent | Safe for Continuous Industrial Service | -325°F to 800°F (-198°C to 426°C) |
| Viton® (FKM Fluoroelastomer) | A-Excellent | Safe for Continuous Industrial Service | -15°F to 400°F (-26°C to 204°C) |
| PTFE (Teflon® / Polytetrafluoroethylene) | A-Excellent | Safe for Continuous Industrial Service | -328°F to 500°F (-200°C to 260°C) |
| EPDM (Ethylene Propylene Diene Monomer) (Current Page) | A-Excellent | Safe for Continuous Industrial Service | -60°F to 300°F (-51°C to 149°C) |
| PVC Type I (Unplasticized Polyvinyl Chloride / uPVC) | A-Excellent | Safe for Continuous Industrial Service | 32°F to 140°F (0°C to 60°C) |
| PVDF (Kynar® / Polyvinylidene Fluoride) | A-Excellent | Safe for Continuous Industrial Service | -40°F to 280°F (-40°C to 138°C) |
| Buna-N (Nitrile / NBR Elastomer) | A-Excellent | Safe for Continuous Industrial Service | -40°F to 250°F (-40°C to 121°C) |
| HDPE (High-Density Polyethylene) | A-Excellent | Safe for Continuous Industrial Service | -60°F to 140°F (-51°C to 60°C) |
Frequently Asked Questions (FAQ)
Is EPDM compatible with Sodium Thiosulfate (25%)?
EPDM is rated A-Excellent (Safe for Continuous Industrial Service) with Sodium Thiosulfate (25%) (Formula: Na2S2O3 (25% aq.), CAS: 7772-98-7). Chemically inert interface with no measurable corrosion, polymer chain scission, or elastomeric swell under standard operating conditions. Approved for continuous fluid handling, bulk storage, valves, and sealing assemblies.
What is the best alternative material for handling Sodium Thiosulfate (25%)?
If EPDM does not meet your temperature or pressure requirements for Sodium Thiosulfate (25%), the highest-rated Grade A alternatives are Polypropylene, Stainless Steel, Viton, PTFE. Always verify O-ring elastomers and metallic fasteners separately before full-scale deployment.
Technical Engineering FAQs: Sodium Thiosulfate (25%) vs EPDM
Click any question below for chemical failure-mode specifics, thermal derating limits, and material selection rules: