Titanium dioxide pigment is produced by one of two industrial processes: the sulfate process and the chloride process. Both can deliver high-quality rutile TiO₂, but they differ in feedstock, particle-size control, environmental profile and cost. Understanding the difference helps you shortlist the right grades before you ever request a sample.
The sulfate process
The older of the two routes, the sulfate process digests ilmenite or titanium slag in sulfuric acid, then hydrolyses, calcines and finishes the pigment. It is flexible — it can produce both anatase and rutile crystal forms — and it tolerates lower-grade feedstock.
- Cost-efficient and versatile for general-purpose applications.
- Widely used in decorative paints, inks, paper and many plastics.
- Particle-size distribution is typically a little broader than chloride grades.
The chloride process
The chloride process reacts high-grade rutile or synthetic rutile feedstock with chlorine to form titanium tetrachloride, which is purified and oxidised at high temperature to rutile TiO₂. It only produces the rutile form, but with very tight particle-size control.
- Narrow particle-size distribution: higher gloss, cleaner undertone, stronger tinting.
- Often preferred for automotive, coil, powder and premium industrial coatings.
- Well suited to demanding plastics and masterbatch where dispersion is critical.
Side by side
- Crystal form
- Sulfate can make anatase or rutile; chloride makes rutile only.
- Particle-size control
- Chloride grades are generally tighter, giving better gloss and tinting strength.
- Cost position
- Sulfate grades are usually more economical; chloride grades command a premium for performance-critical uses.
- Typical uses
- Sulfate: decorative paints, inks, paper, general plastics. Chloride: automotive and industrial coatings, powder coatings, films and engineering plastics.
Which should you choose?
Treat process as a starting filter, not a verdict. A well-made sulfate rutile grade will outperform a poorly matched chloride grade in many formulations. Compare the published specifications — TiO₂ content, oil absorption, dispersibility and surface treatment — and confirm with a trial in your own system.
OxiWhite Global supplies both sulfate and chloride rutile grades. Browse the catalogue to compare them side by side, or read our grade selection guide.