Boron Products / Borax Pentahydrate
Etibor-68. 47.8% B₂O₃. The highest-concentration borax for glass batch and NPK blending.
Na₂B₄O₇·5H₂O — the preferred borax grade where minimising water input per unit of B₂O₃ delivered matters. Glass tank batch engineers select Etibor-68 over decahydrate to reduce batch moisture and maximise boron addition per tonne of material handled. NPK blending plants select it for the same density and flow advantages. Full ICP-OES COA, certificate of origin, and REACH SDS standard on every shipment.
Complete analytical specification
Etibor-68 — every parameter, every test method
| Parameter | Test method | Granular grade | Powder grade | Industrial significance | Comparison: decahydrate |
|---|---|---|---|---|---|
| Na₂B₄O₇ (anhydrous borax) content | Calculated | ≥68.0% (Etibor-68 name basis) | ≥68.0% | Basis of commercial name; determines boron delivery per MT of product purchased | Decahydrate: ~52.8% Na₂B₄O₇ |
| B₂O₃ content | Calculated from Na₂B₄O₇ | 47.8% | 47.8% | Design parameter for all formulations; pentahydrate delivers 31% more B₂O₃ per MT than decahydrate | Decahydrate: 36.5% B₂O₃ |
| Water of crystallisation | Gravimetric loss on ignition | ~30.5% (5 moles H₂O) | ~30.5% | Lower water content vs decahydrate (47.2%) — reduces batch moisture sensitivity in glass manufacturing | Decahydrate: 47.2% H₂O |
| Na₂SO₄ (sodium sulphate) | ICP-OES · Ion chromatography | ≤0.2% | ≤0.2% | Elevated sulphate affects glass melt quality and glaze surface in ceramic applications | ≤0.1% (decahydrate) |
| Iron (Fe) | ICP-OES | ≤10 ppm | ≤10 ppm | Glass colour impurity — relevant for container glass and display glass applications | ≤10 ppm |
| Solubility at 20°C | Gravimetric dissolution test | ~31 g/L | ~31 g/L | Moderate solubility — lower than decahydrate at ambient temperature, increases sharply above 60°C | ~50 g/L (decahydrate preferred for cold-water dissolution) |
| pH (1% aqueous solution) | Potentiometric | ~9.2–9.4 | ~9.2–9.4 | Alkaline in solution — relevant for pH-sensitive formulations and cleaning applications | ~9.3 (decahydrate) |
| Bulk density | ISO 3923 | ~950–1,100 kg/m³ | ~900–980 kg/m³ | Higher bulk density vs decahydrate — more B₂O₃ per unit volume stored and transported | ~800–900 kg/m³ (decahydrate) |
| Particle size (granular) | Sieve analysis · ISO 3310 | -4+100 mesh standard · Fine and coarse grades available | N/A | Particle size matching to NPK fertilizer granule size ensures homogeneous blending | Larger crystal structure in decahydrate |
| Packaging and logistics | |||||
| Packaging options | — | 25 kg PP woven bags | (palletised) · 1,000 kg FIBC big bags | 25 kg PP woven bags | ~22–24 MT per 20' FCL (palletised 25 kg bags) · FOB Bandırma or CIF destination |
Application intelligence — why Etibor-68 is preferred over decahydrate
The six primary applications and the technical reason for grade selection
Glass Batch Manufacturing
Glass technologists select pentahydrate over decahydrate because every tonne of Etibor-68 delivers 47.8% B₂O₃ vs 36.5% from decahydrate — meaning 24% less material handled per unit of boron added to the melt. In high-volume glass tanks processing 200–800 tonnes per day, this material efficiency difference is commercially significant. The lower water content also reduces batch moisture, improving melt homogeneity and reducing energy consumption per tonne of glass produced.
Primary glass flux application
NPK Compound Fertilizer Blending
Granular borax pentahydrate is the industry-standard boron micronutrient additive for compound NPK fertilizers. The granular particle size is matched to NPK granule size distributions (1–4mm) to ensure homogeneous blending without segregation. The higher B₂O₃ content versus decahydrate means less material per tonne of NPK produced — reducing storage, handling, and transport costs per unit of boron delivered to the farmer.
NPK blending industry standard
Welding & Brazing Flux
Borax pentahydrate dissolves metal oxides from the joint surface during silver brazing and copper welding — acting as a chemical flux that enables the filler metal to wet and flow into the joint. The B₂O₃ released during heating forms a liquid slag that floats oxide impurities and prevents re-oxidation of the base metal during the brazing cycle. Pentahydrate is preferred over decahydrate in pre-mixed flux pastes for its lower moisture content and better shelf stability.
Silver brazing · Cu alloy joining
Detergent & Cleaning Formulation
Borax pentahydrate is a classical detergent builder — buffering pH at 9.2–9.4, softening water by complexing calcium and magnesium ions, and acting as a bleach activator in sodium perborate systems. The powder grade is used in powdered laundry detergent formulations; granular for industrial cleaning compound blending. The pentahydrate's lower moisture content provides better powder flow and anti-caking performance than decahydrate in powder detergent applications.
Detergent builder · pH buffer
Wood Preservation & Fire Retardants
Borax pentahydrate dissolved in water is used in pressure treatment and brushed surface application of structural timber — providing protection against Bostrychidae wood borers, Serpula lacrymans dry rot, and Reticulitermes termites. In fire retardant formulations, the B₂O₃ released during combustion forms a protective vitreous layer on the wood surface that limits oxygen access and char propagation.
Wood treatment · FR formulation
Metallurgy & Non-Ferrous Smelting
Borax pentahydrate is used as a covering flux in the smelting of copper, bronze, and precious metals — dissolving metal oxide films from the melt surface and forming a protective slag layer that prevents atmospheric re-oxidation during casting. In gold refining (fire assay), borax flux dissolves the silica gangue minerals and base metal oxides, allowing clean gold separation from the lead button. Pentahydrate is preferred for flux charge control in volumetric assay procedures.
Non-ferrous smelting · Fire assay
Borax pentahydrate — key metrics
47.8%
B₂O₃ content — 31% more boron per MT than borax decahydrate
Etibor-68
Eti Maden brand — 68% anhydrous borax basis; industry-recognised specification
22–24 MT
Per 20' FCL · 25 kg bags palletised · FOB Bandırma
4 hrs
Indicative quotation response — COA, MSDS, and certificate of origin included
Specify annual volume, packaging, and destination. Quotation within 4 working hours.
25 kg bags or 1,000 kg FIBC big bags · FOB Bandırma or CIF destination · COA, MSDS, and Turkish certificate of origin included · Spot and annual framework supply available.
Borax pentahydrate procurement