White spirit

White spirit also known as Stoddard solvent is a paraffin derived clear, transparent liquid which is a common organic solvent used in painting and decorating.

It is a mixture of saturated aliphatic and alicyclic C7 to C12 hydrocarbons with a maximum content of 25% of C7 to C12 alkyl aromatic hydrocarbons .

White spirit is used as an extraction solvent, as a cleaning solvent, as a degreasing solvent and as a solvent in aerosols, paints, wood preservatives, lacquers, varnishes, and asphalt products. In western Europe about 60% of the total white spirit consumption is used in paints, lacquers and varnishes. White spirit is the most widely used solvent in the paint industry.

Three different types and three different grades of white spirit exist. The type refers to whether the solvent has been subjected to hydrodesulfurization (removal of sulfur) alone (type 1), solvent extraction (type 2) or hydrogenation (type 3). Each type comprises three different grades: low flash grade, regular grade, and high flash grade. The grade is determined by the crude oil used as the starting material and the conditions of distillation.

In addition there is type 0, which is defined as distillation fraction with no further treatment, consisting predominantly of saturated C9 to C12 hydrocarbons with a boiling range of 140-200°C.

Physical properties

The physical properties of the three types of white spirit are

Property	T1: Low flash	T2: Regular	T3: High flash
Initial boiling point (IBP) (°C)	130-144	145-174	175-200
Final boiling point (°C)	IBP+21, max. 220
Average relative molecular mass	140	150	160
Relative density (15°C)	0.765	0.780	0.795
Flash point (°C)	21-30	31-54	> 55
Vapour pressure (kPa, 20°C)	1.4	0.6	0.1
Volatility (n-butyl acetate=1)	0.47	0.15	0.04
Autoignition temperature (°C)	240	240	230
Explosion limits (% by volume in air)	0.6-6.5	0.6-6.5	0.6-8
Vapour density (air=1)	4.5-5	4.5-5	4.5-5
Refractive index (at 20°C)	1.41-1.44	1.41-1.44	1.41-1.44
Viscosity (cps, 25°C)	0.74-1.65	0.74-1.65	0.74-1.65
Solubility (% by weight in water)	< 0.1	< 0.1	< 0.1
Kauri-butanol value	29-33	29-33	29-33
Aniline point (°C)	60-75	60-75	60-75
Reactivity	reaction with strong oxidizing agents
Odour threshold (mg/m3)	-	0.5-5	4

References

• World Health Organisation safety sheet