Appearance Colorless liquid Formula C9H12 Melting point -43.78 °C | Molar mass 120.19 g/mol Density 876 kg/m³ | |
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1,2,4-Trimethylbenzene, also known as pseudocumene, is an organic compound with the chemical formula C6H3(CH3)3. Classified as an aromatic hydrocarbon, it is a flammable colorless liquid with a strong odor. It is nearly insoluble in water but soluble in organic solvents. It occurs naturally in coal tar and petroleum (about 3%).
Contents

Production

Industrially, it is isolated from the C9 aromatic hydrocarbon fraction during petroleum distillation. Approximately 40% of this fraction is 1,2,4-trimethylbenzene. It is also generated by methylation of toluene and xylenes and the disproportionation of xylene over aluminosilicate catalysts.
Uses

Pseudocumene is a precursor to mellitic anhydride, from which high performance polymers are made. It is also used as a sterilizing agent and in the manufacture of dyes, perfumes, and resins. Another major use is as a gasoline additive.
Scintillator

1,2,4-Trimethylbenzene dissolved in mineral oil is used as a liquid scintillator in particle physics experiments such as NOνA and Borexino.