Chemical Properties |
clear colourless liquid |
Uses |
Meta-Xylene is used for the production of isophthalic acid, of agriculture chemicals as pharmaceuticals. It finds applications in paint and varnish removers and aerosol paint concentrates. Product Data Sheet |
Definition |
ChEBI: A xylene carrying methyl groups at positions 1 and 3. |
General Description |
A colorless watery liquid with a sweet odor. Less dense than water. Insoluble in water. Irritating vapor. |
Air & Water Reactions |
Highly flammable. Insoluble in water. |
Reactivity Profile |
m-Xylene may react with oxidizing materials. . |
Health Hazard |
Vapors cause headache and dizziness. Liquid irritates eyes and skin. If taken into lungs, causes severe coughing, distress, and rapidly developing pulmonary edema. If ingested, causes nausea, vomiting, cramps, headache, and coma; can be fatal. Kidney and liver damage can occur. |
Fire Hazard |
Behavior in Fire: Vapor is heavier than air and may travel considerable distance to a source of ignition and flash back. |
Safety Profile |
Moderately toxic by intraperitoneal route. Wdly toxic by ingestion, skin contact, and inhalation. An experimental teratogen. Human systemic effects by inhalation: motor activity changes, ataxia, and irritabihty. Experimental reproductive effects. A severe skin irritant. A common air contaminant. A very dangerous fire hazard when exposed to heat or flame; can react with oxidzing materials. Explosive in the form of vapor when exposed to heat or flame. To fight fire, use foam, CO2, dry chemical. Emitted from modern building materials (CENEAR 69,22,91). When heated to decomposition it emits acrid smoke and irritating fumes. See also other xylene entries. |
Purification Methods |
The general purification methods listed under xylene are applicable. The o-and p-isomers can be removed by their selective oxidation when a m-xylene sample containing them is boiled with dilute HNO3 (one part conc acid to three parts water). After washing with water and alkali, the product can be steam distilled, collected as for o-xylene, then distilled and purified further by sulfonation. [Clarke & Taylor J Am Chem Soc 45 831 1923.] m-Xylene is selectively sulfonated when a mixture of xylenes is refluxed with the theoretical amount of 50-70% H2SO4 at 85-95o under reduced pressure. By using a still resembling a Dean and Stark apparatus, water in the condensate can be progressively withdrawn while the xylene is returned to the reaction vessel. After cooling, then adding water, unreacted xylenes are distilled off under reduced pressure. The m-xylene sulfonic acid is subsequently hydrolysed by steam distillation up to 140o, the free m-xylene is washed, dried with silica gel and again distilled. It is stored over molecular sieves Linde type 4A. [Beilstein 5 H 370, 5 I 182, 5 II 287, 5 III 823, 5 IV 932.] |