CAS 7705-08-0 · Coagulant · 37–42% Solution
Ferric Chloride
FeCl₃ · MW 162.20 g/mol · Iron(III) Chloride
The coagulant of choice for water and wastewater treatment — ferric chloride's high charge density and wide effective pH range make it superior to alum in many applications, particularly for phosphorus removal and sludge conditioning. Texas-Chem supplies FeCl₃ in 37–42% solution in drums, totes, and bulk tanker quantities.
Formula
FeCl₃
pH (solution)
1–2
Concentration
37–42%
Pack Sizes
Drums · Totes · Bulk
Structural Formula
Iron(III) with three chloride ligands — Fe³⁺ is the active coagulating species in solution
Safety & Regulatory
- NFPA Health
- 2 — Moderate hazard
- NFPA Flammability
- 0 — Non-flammable
- NFPA Reactivity
- 1 — Slight hazard
- OSHA PEL (Fe dust)
- 10 mg/m³
- DOT Hazard Class
- 8 — Corrosive
- UN Number
- UN 2582 (solution)
- Incompatibilities
- Strong bases, oxidizers; corrosive to most metals
- Special Hazard
- Highly corrosive to concrete, stainless steel, and most metals
Highly corrosive — use acid-resistant PPE and equipment. Avoid contact with concrete and most metals. SDS available upon request.
Grades & Packaging
Available Grades
Pack Sizes
Physical & Chemical Properties
| Molecular Formula | FeCl₃ |
| Molecular Weight | 162.20 g/mol |
| CAS Number | 7705-08-0 |
| Physical Form | Dark brown liquid (solution) or dark solid |
| Boiling Point | 315 °C (anhydrous) |
| Flash Point | Non-flammable |
| Density | 1.35–1.42 g/cm³ (37–42% solution) |
| pH | 1–2 (strongly acidic solution) |
| Solubility | 920 g/L at 20 °C (highly soluble) |
| Odor | Slight HCl odor |
| Color | Dark reddish-brown |
| Vapor Pressure | Negligible at 20 °C |
Industrial Applications
Municipal Water Coagulation
Primary coagulant for drinking water treatment — ferric chloride destabilizes colloidal particles and suspended solids by charge neutralization and sweep flocculation, forming settleable floc. Effective over a wide pH range (4–11).
Wastewater Treatment
Coagulant and phosphorus removal agent in municipal and industrial wastewater treatment. Ferric chloride reacts with soluble phosphate to form insoluble ferric phosphate, achieving >90% phosphorus removal.
Sludge Conditioning
Conditioning agent for municipal biosolids before belt press or centrifuge dewatering. Ferric chloride improves sludge dewaterability by destabilizing the colloidal structure of biosolids, reducing polymer demand.
Printed Circuit Board Etching
Etchant for copper in PCB manufacturing — ferric chloride oxidizes and dissolves copper traces, defining circuit patterns. Used in both spray and immersion etching processes for electronics fabrication.
Odor Control
Hydrogen sulfide scavenger in wastewater collection systems — ferric chloride reacts with H₂S to form insoluble iron sulfide, controlling sewer odors and corrosion in force mains and wet wells.
Industrial Wastewater
Coagulant for removing heavy metals, turbidity, and color from industrial effluents including textile, tannery, and metal finishing wastewater. Effective for treating high-strength industrial streams.
Why Source Ferric Chloride from Texas-Chem?
- 35+ years supplying coagulants to Texas water utilities and industrial customers
- 37%, 40%, and 42% solution grades available
- Drums, totes, and bulk tanker delivery with corrosive-rated equipment
- Competitive pricing backed by top-tier producer relationships
- Technical support and SDS documentation with every order
- Same-day quotes for standard quantities