CAS 57-13-6 · ISO 22241 / API Certified · AUS 32
Diesel Exhaust Fluid (DEF)
CO(NH₂)₂ · 32.5% Urea Solution · AUS 32 / AdBlue® Equivalent
Chemical & Filtration Products of Texas supplies ISO 22241 and API certified Diesel Exhaust Fluid to trucking fleets, construction operators, agricultural businesses, and industrial facilities across Texas and the Gulf Coast. DEF is a precisely formulated 32.5% aqueous urea solution required by all SCR-equipped diesel engines to meet EPA NOx emissions standards. We offer 275-gallon totes and bulk tanker delivery — with scheduled supply programs available for high-volume fleet and industrial customers.
Composition
32.5% Urea / Water
Freeze Point
−11 °C (12 °F)
pH
9.0–9.5
Pack Options
Totes · Bulk Tanker
Chemical Formula
Urea hydrolyzes in the SCR catalyst to produce ammonia, which reduces NOx to N₂ and H₂O
Safety & Regulatory
- NFPA Health
- 1 — Slight hazard
- NFPA Flammability
- 0 — Non-flammable
- NFPA Reactivity
- 0 — Stable
- DOT Classification
- Not regulated as hazardous material
- ISO Standard
- ISO 22241-1 (quality), 22241-2 (test methods)
- API Certification
- API Certified DEF available
- Incompatibilities
- Copper, zinc, and their alloys (causes contamination)
- Storage Temp
- −11 °C to 25 °C; avoid prolonged heat above 30 °C
Grades & Packaging
Available Grades
Pack Sizes
Why 32.5%?
The 32.5% urea concentration is the eutectic point — the mixture that freezes at the lowest possible temperature (−11 °C). This is mandated by ISO 22241 to ensure consistent SCR performance and prevent crystallization in vehicle tanks and storage equipment.
Physical & Chemical Properties
| Chemical Composition | 32.5% high-purity urea + 67.5% deionized water |
| CAS Number (Urea) | 57-13-6 |
| Molecular Formula (Urea) | CO(NH₂)₂ |
| Molecular Weight (Urea) | 60.06 g/mol |
| Physical Form | Clear, colorless aqueous solution |
| Density | 1.087–1.093 g/cm³ at 20 °C |
| Freezing Point | -11 °C (12 °F) |
| Boiling Point | ~103 °C |
| pH | 9.0–9.5 |
| Flash Point | Non-flammable |
| Odor | Slight ammonia odor |
| Purity Standard | ISO 22241-1 / API Certified DEF |
Industrial Applications
Heavy-Duty Diesel Trucks
Required by all 2010+ EPA-compliant diesel trucks equipped with Selective Catalytic Reduction (SCR) systems. DEF is injected into the exhaust stream, converting NOx emissions into harmless nitrogen and water vapor. Typical consumption is 2–3% of diesel fuel volume.
Construction & Mining Equipment
Off-road diesel equipment — excavators, loaders, haul trucks, and drilling rigs — equipped with Tier 4 Final engines require DEF to meet EPA non-road emissions standards. Bulk DEF delivery keeps job sites and mine operations running without interruption.
Agricultural Equipment
Modern tractors, combines, and large agricultural equipment with Tier 4 engines use SCR systems requiring DEF. Farm operations benefit from bulk tote and drum delivery to reduce per-gallon cost and ensure continuous availability during planting and harvest seasons.
Fleet & Transportation
Trucking fleets, bus operators, and logistics companies with large diesel vehicle inventories rely on bulk DEF supply programs. Texas-Chem provides scheduled delivery and on-site storage solutions to keep fleets compliant and moving.
Power Generation
Diesel generator sets and stationary diesel engines used in data centers, hospitals, and industrial facilities with SCR emissions controls require DEF. Bulk supply ensures backup power systems remain compliant and ready.
Marine & Rail
Large marine diesel engines and locomotive engines equipped with SCR systems use DEF to meet Tier 4 emissions requirements. Bulk delivery to ports, rail yards, and marine terminals is available throughout Texas and the Gulf Coast region.
Why Source DEF from Texas-Chem?
- 35+ years supplying industrial chemicals to Texas fleets and operators
- ISO 22241 and API certified DEF — protects SCR systems and warranties
- Flexible packaging: 275-gallon totes and bulk tanker delivery
- Scheduled supply programs for high-volume fleet and industrial customers
- Full SDS documentation and lot traceability on every order
- Same-day quotes for standard quantities
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Diesel Exhaust Fluid vs. Alternatives
Diesel Exhaust Fluid (DEF) is a precisely formulated urea-water solution for SCR emissions control. Here's how DEF quality tiers compare.
| Attribute | Diesel Exhaust Fluid | Agricultural Urea Solution | Technical Urea Solution |
|---|---|---|---|
| Urea Concentration | 32.5% ± 0.7% (ISO 22241) | Variable — not SCR-grade | Variable — may contain impurities |
| Purity Standard | ISO 22241 / API certified | No SCR standard | No SCR standard |
| NOx Reduction | 70–95% NOx reduction in SCR | Catalyst damage risk | Catalyst damage risk |
| Freezing Point | −11 °C (12 °F) | Varies | Varies |
| Packaging | 2.5 gal jugs, 55 gal drums, 275 gal totes, bulk | Bulk only | Bulk or drums |
Industries We Supply Diesel Exhaust Fluid To
Trucking & Commercial Fleet
ISO-certified DEF is required for all EPA 2010+ diesel trucks with SCR systems — fleets require reliable bulk supply to maintain uptime and regulatory compliance.
Diesel Exhaust Fluid supply in Dallas, TXConstruction & Mining Equipment
Off-road diesel equipment with Tier 4 Final engines requires DEF for SCR operation — construction sites and mines need on-site bulk storage and delivery.
Diesel Exhaust Fluid supply in Midland, TXAgriculture & Farm Equipment
Modern agricultural tractors and combines with SCR systems require DEF — farms need reliable supply during planting and harvest seasons.
Diesel Exhaust Fluid supply in Lubbock, TXPower Generation
Stationary diesel generators and gas turbines with SCR systems require DEF for NOx control — critical for backup power at hospitals, data centers, and industrial facilities.
Diesel Exhaust Fluid supply in Houston, TX