About This Product
Mixed xylenes are the heaviest of the BTX streams: the cut that remains once benzene and toluene have been distilled off the aromatic extract of catalytic reformate. The product is not a single compound but a blend of the ortho, meta and para isomers of xylene together with ethylbenzene, all boiling so close together that they distil as one fraction. That blend is what solvent users buy; producers of pure para- or ortho-xylene separate it further by fractionation, crystallisation or adsorption, often combined with isomerisation. Because the product is a blend, its distillation specification is wider than for benzene or toluene: a range within 5°C (including 139.3°C), an initial boiling point of min 137 °C and a dry point of max 143 °C. For a coatings formulator these limits fix the evaporation profile. The IBP floor keeps out lighter aromatics that would speed up flash-off, and the dry point ceiling ensures there is no heavy tail to linger in the film and slow hardening. Non-aromatic hydrocarbons are held at max 4.0 vol %, so solvency stays close to that of a pure aromatic. Specific gravity is 0.8650 – 0.8750 and colour (Pt-Co) max 20. The nitration grade tests are the same family as for the lighter aromatics: acid wash colour max 6, nil acidity, no H2S & SO2 in the sulphur compounds test and a non-corrosive copper strip. The acid wash limit is looser than for benzene or toluene, which suits a heavier, multi-component cut, but it still screens out olefins that would darken in contact with acid. Isomer ratio and ethylbenzene content are not fixed by this datasheet, so buyers who need either within limits should state them at enquiry. Xylenes evaporate more slowly than toluene, giving coatings more open time, better flow and levelling and less risk of blushing in humid conditions. They are a standard solvent for epoxy, alkyd and polyurethane coatings, automotive and industrial finishes, baking enamels and synthetic resin solutions, and the usual aromatic carrier in emulsifiable concentrate pesticide formulations. In synthesis they are nitrated to nitroxylenes and reduced to xylidines for dye and agrochemical intermediates. Among the aromatics listed here, benzene is the feedstock, toluene the quicker solvent and the TDI precursor, and mixed xylenes the slower, higher-boiling solvent. Bio Green Chem supplies mixed xylenes of Pakistani origin, with packaging confirmed per offer according to quantity and route. Each lot is tested and reported on a certificate of analysis, the xylenes technical datasheet is posted here for reference, and an SDS describing flammability and exposure precautions can be requested.
