Xylene is a clear, colorless, sweet-smelling solution of three aromatic hydrocarbon isomers produced from crude oil through a process called alkylation. Xylene consists of three distinct isomers: paraxylene, orthoxylene and metaxylene. Xylene is both naturally occurring and manmade, and is widely used as a solvent in the leather, rubber and printing industries. Other applications of xylene include chemical intermediates, and high-motor and aviation gasoline blending agents. Xylene is also used in breathing devices (inhalers) for administering artificial respiration because of its intoxicating properties. In small doses, it produces euphoria and disinhibition, but it also causes dizziness and hallucinations.
Xylene is a raw material in the production of a monomer (a simple compound with molecules that join together to form polymers) called terephthalic acid. Terephthalic acid is used in the manufacture of polymers (naturally occurring or synthetic compounds consisting of large molecules). It is a good cleaning agent for silicon wafers and steel. It is also used to sterilize many substances. Xylene is used as a feedstock in the production of petrol. It is also found in small proportions in gasoline and jet fuel.
Xylene is one of the most copiously produced chemicals in the United States. It is extensively used as a thinner and solvent in paints, varnishes, adhesives and inks. A xylene mixture can be used to thin lacquers (a black resinous substance used a natural varnish) when slower drying is desired. Xylene is often used as a solvent in pesticides products.
Applications of Paraxylene
Paraxylene is one of the isomers of xylene. It is a colorless, volatile liquid. Paraxylene is a very important raw material in the preparation of PET (polyethylene terephthalate) chips, which are extensively used in packing industries, for example, for mineral water and carbonated soft drink bottles. Paraxylene is also used in the manufacture of PTA (purified terephthalic acid), which is a basic petrochemical used in the textile industry for making polyester.
Use in Histology
Xylene is used in histology to clean tissue for the preparation of paraffin wax. It is also used to prepare very thin slice of tissues for microscopic examination by making them hydrophobic (i.e. lacking affinity for water) so a coverslip can be used.
The majority (more than 90 percent) of mixed xylene isomers is used for blending into petrol and gasoline, and the rest in different solvent applications for the printing industry, pharmaceuticals, perfumes, fabricated items and pesticide formulations, to name a few. Xylene is also used in the preparation of individual isomers, which are often used in making certain types of plastics.