Sodium Chloride NaCl - PDV salt 99.9%

SODIUM CHLORIDE

PDV SALT

Glacia Standard

A Pure Dried Vacuum Salt.

PDV Salt stands for Pure Dried Vacuum Salt — a high-purity, fine-grained sodium chloride (NaCl) produced by vacuum evaporation of brine. It is >99.9% pure, clean, and free-flowing. It has a bulk density of between 1.22 and 1.32 gcm-3. Pure dried vacuum salt is suitable for a  wide range of general applications including chemical, industrial and water treatment where quality and purity are paramount. Commonly used in textile & dye manufacture, Shampoo & detergent manufacture

Specification:

• Chemical Name: Sodium Chloride
• Synonyms: Halite
• Formula: NaCl
• CAS Number: 7647–14–5
• EINECS Number: 231–598–3
• Appearance : Crystalline solid
• Colour : White / Colourless
• pH : 10.0 approx. (10% solution)
• Boiling Point : 1413oC
• Melting Point : 802oC
• Flammability : Non-flammable
• Flash Point : Non-flammable
• Explosive Properties : Non-flammable
• Oxidising Properties : Non-flammable
• Vapour Pressure : 2.4mm Hg at 747oC
• Density : 2.165 g cm-3 (of crystalline solid at 20oC)
• Water Solubility : 35.9 g/100g at 0oC 39.2 g/100g at 100oC

A typical sieve analysis is as follows:

• 100% passes through 1400 micron sieve.
• max. 8% retained on 850 micron sieve.
• max. 56% retained on 425 micron sieve.
• max. 91% retained on 300 micron sieve.

Industrial & Agricultural Uses

• Chemical manufacture: Feedstock for chlorine, caustic soda, sodium-based chemicals

• Textiles & dyeing: Fixing agent in reactive dye baths (see below)

• Soap and detergent production: Filler and viscosity modifier

• Water softening & regeneration: In granulated or briquetted form

• Oil drilling fluids: Controls density and stabilises formations

• Preservative for silage and hay

Health & Safety:

Under the Classification, Packaging and Labelling of Dangerous Substances Regulations, 1984, this material is not dangerous for supply or conveyance.

PLEASE NOTE: This product is not for human consumption and is not to be used in food processing.

Role of PDV Salt in Reactive Dyeing

Key Function: Promotes Dye Exhaustion

• PDV salt reduces the solubility of reactive dyes in water.

• This forces the dye to leave the solution and migrate onto the fibre.

• The salt neutralises the negative charge on the cotton surface and on the dye molecules, allowing the dye to come into close contact with the fibre.

How It Works — Step-by-Step

1. Start of dye bath:

   • Fibre (e.g., cotton) is suspended in a bath with reactive dye + water.

   • Dye molecules and fibre both carry negative charges, so they repel each other.

2. Salt addition (e.g., PDV salt):

   • The salt (NaCl) releases Na⁺ ions into solution.

   • Na⁺ ions screen or neutralise the fibre's negative charge, allowing dye molecules to approach the fibre.

3. Dye exhaustion:

   • The dye now moves from the water phase to the fibre surface.

   • Once there, dye reacts with the fibre (with alkali assistance in the next step).

4. Alkali addition (e.g., soda ash):

   • After dye exhaustion, an alkali is added to initiate the covalent bonding between dye and fibre.