Calcium Nitrate, Calcium Dinitrate, Calcium Nitrate Anhydrous, Nitro Calcite, 10124-37-5

Calcium Nitrate, Calcium Dinitrate, Calcium Nitrate Anhydrous, Nitro Calcite, 10124-37-5

CALCIUM NITRATE

1. PRODUCT DEFINITION AND CHEMICAL IDENTITY

Note: Calcium nitrate is an inorganic salt, also known historically as Norwegian saltpetre or lime nitrate. It is highly soluble in water and is commercially recognized as the first nitrogen fertilizer ever marketed. It provides two essential plant nutrients—calcium and nitrate nitrogen—in a readily available form. Its hygroscopic nature requires proper storage. Beyond agriculture, it is used in industrial explosives, concrete acceleration, heat transfer fluids, and wastewater treatment.

2. PHYSICAL AND CHEMICAL PROPERTIES

3. FUNCTIONAL PROPERTIES AND MODE OF ACTION

• Dual Nutrient Fertilizer (Agriculture): As a fully water-soluble fertilizer, it is a direct source of two essential plant nutrients. The nitrate-nitrogen (NO₃⁻) is immediately available for plant uptake, promoting rapid vegetative growth without the need for soil microbial conversion. The water-soluble calcium (Ca²⁺) is crucial for strengthening cell walls, improving fruit firmness, and preventing physiological disorders like blossom end rot in tomatoes and peppers, and bitter pit in apples.

• Concrete Setting Accelerator (Construction): Calcium nitrate acts as an effective set accelerator for concrete, particularly in cold weather concreting. It accelerates the hydration of cement, shortening the initial and final setting times and allowing for earlier strength development.

• Latex Coagulant (Industrial): In the dipping production of rubber latex goods (e.g., gloves, balloons), calcium nitrate solutions serve as a coagulant bath. The calcium ions destabilize the latex emulsion, causing the rubber particles to deposit and form a uniform film on the mould.

• Heat Transfer and Energy Storage (Energy): In its molten state, calcium nitrate and its blends (e.g., with potassium and sodium nitrate) are used as heat transfer fluids and for thermal energy storage in concentrated solar power (CSP) plants due to their high heat capacity and thermal stability.

• Odour and Corrosion Control (Wastewater): When added to wastewater, calcium nitrate provides an alternative oxygen source (via nitrate respiration), preventing the formation of septic, odorous hydrogen sulfide (H₂S) gas and controlling corrosion in sewer systems.

4. CHEMICAL FORMS

5. SECTORAL APPLICATIONS AND USAGE RATES

6. PRODUCTION METHODS

A. Standard Industrial Process:
Limestone (calcium carbonate, CaCO₃) is reacted with nitric acid (HNO₃), producing calcium nitrate, carbon dioxide, and water:
CaCO₃ + 2 HNO₃ → Ca(NO₃)₂ + CO₂ + H₂O

B. Odda Process (Historical):
Developed in Porsgrunn, Norway, in 1905. Calcium hydroxide (lime water) was reacted with nitric acid to produce calcium nitrate tetrahydrate. This was a cost-effective, efficient production method that made Norway a historic centre for calcium nitrate production, hence the trade name "Norwegian Saltpetre."

7. ALTERNATIVE NAMES AND SYNONYMS

8. ALTERNATIVES AND COMPARISON

9. SAFETY, STORAGE, AND REGULATORY INFORMATION

• GHS Classification (CLP Regulation):

  • Signal Word: Warning (as a strong oxidizer)

  • Hazard Statements: H272 (May intensify fire; oxidizer), H315 (Causes skin irritation), H319 (Causes serious eye irritation).

  • Precautionary Statements: P210, P220, P264, P280, P302+P352, P305+P351+P338, P332+P313, P337+P313, P370+P378, P501.

• NFPA 704: Health: 1, Fire: 0, Reactivity: 3 (OX) – It is a strong oxidizer.

• Storage:

  • Store in a dry and cool place, away from direct sunlight and moisture, in tightly sealed containers.

  • The product is highly hygroscopic; exposure to humid air will cause caking and liquefaction.

  • Keep strictly separate from combustible materials, fuels, and reducing agents (e.g., organic matter, sulfur, metal powders) to prevent fire or explosion.

  • Store away from incompatible chemicals like pesticides and strong acids.

• Personal Protective Equipment (PPE): Use nitrile gloves, safety goggles, and a dust mask. Ensure adequate ventilation.

• Environmental Impact: Runoff from excessive agricultural use can lead to eutrophication of water bodies and nitrate contamination of groundwater.

10. FREQUENTLY ASKED QUESTIONS

Q1: What are the benefits of using calcium nitrate fertilizer?
It provides plants with two essential nutrients: immediately available nitrate-nitrogen for rapid growth and water-soluble calcium for strengthening cell walls. This dual action improves fruit firmness, prevents calcium-deficiency disorders (like blossom end rot and bitter pit), and enhances overall crop quality and shelf life.

Q2: How does calcium nitrate prevent blossom end rot in tomatoes and peppers?
This disorder is caused by a localized calcium deficiency in the developing fruit, often triggered by inconsistent watering. Calcium nitrate provides readily soluble calcium that can be taken up by the plant, ensuring a steady supply to the rapidly growing tissues, thereby preventing the characteristic necrotic spots.

Q3: Why is calcium nitrate hygroscopic?
The nitrate ion (NO₃⁻) has a strong affinity for water molecules. The anhydrous form of calcium nitrate will actively pull moisture from the surrounding air until it forms a saturated solution, which is why it must be stored in airtight packaging.

Q4: Is calcium nitrate the same as ammonium nitrate?
No. Calcium nitrate (Ca(NO₃)₂) provides calcium and nitrogen. Ammonium nitrate (NH₄NO₃) provides only nitrogen. They have different chemical properties, with calcium nitrate being a non-volatile source of nitrogen that is directly plant-available.

11. QUICK REFERENCE TABLE