Salt Flux – NaCl–KCl (General Purpose)
A NaCl-KCl General Purpose Salt Flux is an inorganic mixture of Sodium Chloride (NaCl) and Potassium Chloride (KCl). It is valued in the metal casting industry, particularly with aluminum, for forming a low-melting, highly effective molten salt layer. This layer serves both a passive (protective cover) and an active (cleaning and metal recovery) role in the melt.
The most common general-purpose composition is often an equimolar mixture ( 45% NaCl and 55% KCl) which forms a low-temperature eutectic (~665°C), ensuring the flux is liquid well below the typical aluminum casting temperatures (~700°C).
Main Components and Function
The chloride blend creates a molten bath separate from the metal, promoting cleanliness and efficiency.
| COMPONENT | CHEMICAL FORMULA | PROPERTY HIGHLIGHT |
| Sodium Chloride | NaCl | Base component, contributes to low eutectic melting point. |
| Potassium Chloride | KCl | Base component, controls density and melting point. |
| CLASSIFICATION | EUTECTIC T | PRIMARY APPLICATION FOCUS |
| Chloride Flux | ~665°C (1229 F) | Aluminum scrap melting, dross treatment, and oxidation cover. |
Key Performance Metrics
| PROPERTY | TYPICAL PERFORMANCE | MECHANISM OF ADVANTAGE |
| Low Melting Point | EXCELLENT | Melts and becomes active quickly at non-ferrous casting temperatures. |
| Wettability | STRONG | Has a strong ability to wet aluminum oxide (Al2O3), stripping the oxide film from metal droplets. |
| Density Differential | IDEAL | Specific gravity is significantly lower than molten aluminum, ensuring the flux floats on the metal surface. |
| Metal Recovery | HIGH | Promotes the coalescence (gathering) of fine metal droplets trapped in dross. |
Dual Function in Aluminum Processing
The NaCl-KCl salt mixture performs critical functions, especially in secondary aluminum production (recycling):
- Passive Role (Cover Flux):
- Oxidation Prevention: A molten layer of the salt is maintained on the surface of the aluminum melt. This barrier physically separates the liquid metal from the oxidizing atmosphere, drastically minimizing the formation of dross (aluminum oxides) and reducing metal loss.
- Inclusion Scavenging: The molten salt layer acts as a physical medium to absorb and aggregate non-metallic impurities and inclusions that rise from the metal bath.
- Active Role (Dross Treatment/Metal Recovery):
- Coalescence: During the melting of scrap or the treatment of dross, the salt flux chemically attacks the thin oxide films surrounding individual metal droplets. By stripping this oxide shell, the clean aluminum droplets are allowed to fuse (coalesce) with the main metal bath, significantly improving metal yield from low-grade scrap or dross skimming.
Comparison and Customization
- Simple Chloride: This binary mix is considered a basic chloride flux. For more aggressive cleaning (refining) or to target specific impurities (like magnesium, Mg), other chloride or fluoride components are added.
- Additive Platform: The NaCl-KCl base is commonly modified with fluorides (e.g., CaF2, Na3AlF6) to increase the dissolution and stripping power of the flux, especially for difficult oxide inclusions, or MgCl2 to enhance magnesium removal.
Typical Industries and Applications
- Aluminum Recycling: Used in rotary furnaces and reverberatory furnaces to maximize metal recovery from contaminated scrap and dross.
- Aluminum Casting: Used as a simple cover flux in holding furnaces and ladles to prevent oxidation before pouring.
- Foundries: Used in other non-ferrous operations where a basic, protective, and cleaning salt layer is beneficial.
Technical Guidance
- Application: The flux is applied to the surface of the melt as a powder or granules and is then allowed to melt and form a protective layer. It may be stirred to bring contaminated metal into contact with the salt.
- Waste Management: The spent salt flux, which contains high concentrations of metal oxides and impurities, is removed as a solid residue and requires specific disposal procedures, though the chloride components themselves are less regulated than fluoride additives.
✨ Customization Services
We offer product customization services, allowing you to tailor the appearance, dimensions, or specific markings of items like refractory shapes or bricks. This includes options for incorporating specific geometric requirements to ensure seamless integration into your process systems.
🔬 Sampling for Testing & Validation
Free product samples are available for thorough testing and validation. This allows you to confirm the quality, compatibility, and performance of our materials—such as specific bricks, castables, or raw materials—before committing to a full order.
💡 Expertise in Refractory Solutions
Leverage our deep expertise to receive detailed, application-specific refractory solutions. We move beyond just selling products by providing comprehensive plans that encompass material selection, installation guidance, and performance optimization to maximize the lifespan and efficiency of your high-temperature processes.
Rabatec products are exclusively manufactured in facilities that have achieved rigorous ISO certifications across Quality (ISO 9001), Environmental Management, and Occupational Health & Safety. This commitment ensures every product, from refractory bricks to specialized equipment, meets the highest global benchmarks for performance, sustainability, and workplace safety.
📦 Logistics Excellence: Shipping, Packaging, and Marking
Minimizing Risk: We manage all logistics to minimize handling touchpoints and transit shock. Our carriers are pre-vetted for their experience in transporting heavy, fragile, and sensitive industrial materials.
Traceability: Every shipment includes comprehensive documentation and tracking information, providing end-to-end visibility and ensuring precise delivery coordination for your site.
Protection is Paramount: Our packaging strictly follows industry standards to prevent damage, corner chipping, and moisture absorption—especially critical for materials like Basic Refractory Bricks and Refractory Mortars & Mixes.
Robust Palletization: Products are secured on fumigated, high-strength export pallets (e.g., 1100x950mm or similar sturdy dimensions) using heavy-duty strapping and durable protective wrapping (polyethylene sheeting, cardboard, etc.) to withstand long-distance travel and multiple loadings.
Moisture Control: Sensitive materials are protected with appropriate sealing and, where necessary, desiccants or moisture-vapor proof enclosures to maintain the product's integrity until installation.
Clear Identification: All outer packaging is clearly marked on multiple sides with large, legible text for immediate identification and safe handling.
Full Traceability: Markings include all essential data points: Product Name, Quality Grade, Batch Number, Quantity, Net/Gross Weight, Order Number, and the Final Destination/Construction Area. This ensures every pallet can be accounted for and correctly staged upon arrival.
Safety & Compliance: We adhere to all regulatory requirements for marking, labeling, and placarding—especially for any items classified as Dangerous Goods—to ensure full compliance with international and domestic transport regulations.
❓ Frequently Asked Questions (FAQ)
Question | Elaborated Answer |
Q: What is the Refractoriness Under Load (RUL) of your refractories? | A: Refractoriness Under Load (RUL) is a critical property that defines the maximum temperature our materials can withstand while under compressive stress before deforming (softening). Since we offer a wide range of materials—from Alumina-Silicate Bricks to high-performance Silicon Carbide Bricks—the RUL varies significantly. For specific product data, please refer to the product data sheet or submit a quote request for the material you are interested in. |
Q: Where are the Rabatec refractories and materials produced? | A: Our products are primarily sourced from specialized manufacturing plants in China. Crucially, these facilities have all undergone rigorous audits and achieved comprehensive ISO certifications (Quality, Environment, and Safety), ensuring that production adheres to the highest global standards for consistency and performance. |
Q: What refractory materials does the company offer? | A: We supply a comprehensive portfolio of advanced refractory solutions, including: Shaped Products: Alumina & Silica Bricks, Basic & Specialized Bricks (e.g., Magnesia), SiC & Structural Ceramics, and Precast Shapes. Monolithic Products: Refractory Castables, Mixes & Mortars. Insulation: Insulation Fibre and High-Performance Insulation Products. |
Q: How should I choose the appropriate refractory material for my application? | A: Selecting the correct refractory is paramount to process efficiency. The choice depends on three key factors: 1. Operating Environment: Maximum process temperature and thermal cycling (shock). 2. Chemical Attack: Type of slag, molten metal, or corrosive gas being handled (acidic, neutral, or basic). 3. Mechanical Stress: Abrasion, erosion, and static load requirements. We recommend utilizing our detailed refractory solutions service to consult with our engineers for an optimized, application-specific recommendation. |
Q: Which monolithic material should I choose when patching an existing lining? | A: For patching and minor repairs, the ideal monolithic material depends on the parent lining material, the patching depth, and the need for a rapid return to service. Common choices include: Refractory Mortars & Mixes (for minor joints/surfaces) or Plastic Refractories (for areas requiring physical compaction). Always choose a patch material chemically compatible with the existing lining to ensure proper bonding and service life. |
Q: Can I receive product samples before placing a major order? | A: Yes. We gladly provide product samples for your internal testing and validation purposes. This ensures you can confirm the quality, composition, and fit of the material—such as our Refractory Castables or Alumina-Silicate Bricks—in your specific operational environment before committing to a bulk purchase. |
Q: Do you provide certifications to verify material quality? | A: Absolutely. We provide product-related inspection certificates and quality assurance documentation upon request. This verifies that your order has passed all internal quality control checks and meets the required material specifications and industry standards. |
Q: What measures are taken for product protection during transport? | A: We ensure quick, reliable transport by using robust, industrial packaging that strictly follows industry standards. This includes high-strength palletization, heavy-duty strapping, and weather-resistant wrapping to protect fragile items like bricks and mixes from corner chipping, mechanical damage, and moisture during transit. |
