User:Milton Beychok/Sandbox: Difference between revisions
imported>Milton Beychok |
imported>Milton Beychok No edit summary |
||
| Line 13: | Line 13: | ||
In the petroleum and petrochemical industries, the acronym '''BTX''' refers to mixtures of the aromatic hydrocarbons benzene, toluene, and the three xylene isomers. If ethylbenzene is included, the mixture is sometimes referred to '''BTEX'''. The xylene isomers are distinguished by the designations ortho | {{Image|BTX.png|right|350px|Structural diagrams of the BTX aromatic hydrocarbons.}} | ||
In the petroleum and petrochemical industries, the acronym '''BTX''' refers to mixtures of the aromatic hydrocarbons benzene, toluene, and the three xylene isomers. If ethylbenzene is included, the mixture is sometimes referred to '''BTEX'''. The xylene isomers are distinguished by the designations ''ortho'' – (''o''&thinssp;–), ''meta'' – (''m'' –), and ''para'' – (''p'' –). | |||
The BTX aromatics are very important petrochemical materials. The world wide demand for these hydrocarbons is steadily increasing. The demand for xylenes, particularly para | The BTX aromatics are very important petrochemical materials. The world wide demand for these hydrocarbons is steadily increasing. The demand for xylenes, particularly ''para'' –xylene, has increased in proportion to the increase in demand for polyester fibers and film. Benzene is a highly valuable product for use as a chemical raw material. Toluene is also a valuable petrochemical for use as a solvent and intermediate in chemical manufacturing processes and as a high octane gasoline component. | ||
Revision as of 12:57, 17 March 2012
References
- ↑ The BTX Chain: Benzene, Toluene, Xylene. Chapter 4 of the DOE's Office of Energy Efficiency and Renewable Energy (EERE) report entitled "Energy and Environmental Profile of the U.S. Chemical Industry" of May 2000.
- ↑ Benzene/Toluene. Introduction to a ChemSystems report, 2009.
- ↑ Use of Process Analytics in Aromatics (BTX and phenol) production plants. Case Study, August 2008.
- ↑ International Energy Agency (2006).Energy Technology Perspectives. 1st Edition. Organisation for Economic Co-operation and Development (OECD). Page 414. ISBN 08070-1556-3.
- ↑ 10.6 Aromatics, Online Italian Encyclopedia of Hydrocarbons, Istituto della Enciclopedia Italiana, Volume II, 2006, pages 603-605.
- ↑ Robert C. Weast (Editor) (1975). Handbook of Chemistry and Physics, 56th Edition. CRC Press. ISBN 0-87819-455-X.
In the petroleum and petrochemical industries, the acronym BTX refers to mixtures of the aromatic hydrocarbons benzene, toluene, and the three xylene isomers. If ethylbenzene is included, the mixture is sometimes referred to BTEX. The xylene isomers are distinguished by the designations ortho – (o&thinssp;–), meta – (m –), and para – (p –).
The BTX aromatics are very important petrochemical materials. The world wide demand for these hydrocarbons is steadily increasing. The demand for xylenes, particularly para –xylene, has increased in proportion to the increase in demand for polyester fibers and film. Benzene is a highly valuable product for use as a chemical raw material. Toluene is also a valuable petrochemical for use as a solvent and intermediate in chemical manufacturing processes and as a high octane gasoline component.
Benzene, toluene, and xylenes can be made by various processes. Most aromatics production is based on the recovery of aromatics derived from the catalytic reforming of naphtha. Catalytic reforming processes utilize a feed containing C6+ non-aromatic hydrocarbons and typically produce a reformate comprised of A6-A8 aromatics (benzene, toluene, xylenes) along with paraffins and heavier aromatics.
Another process for producing aromatics involves the dehydrocyclo-oligomerization of C2-C5 aliphatic hydrocarbons. That process typically produces a product comprised of benzene, toluene, xylenes, C5+ paraffins, C4− light paraffins, olefins, and unreacted C2-C5 aliphatic hydrocarbons.
Still another process for producing aromatics involves the cracking of hydrocarbons such as by steam cracking or catalytic cracking. That process typically produces a cracked naphtha product comprised of C6+ non-aromatic cyclic hydrocarbons, A6-A8 aromatic hydrocarbons (benzene, toluene, xylenes and ethylbenzene), and A9+ aromatic hydrocarbons.
With the world wide demand for benzene, toluene, and xylenes steadily increasing, there is a need for additional benzene, toluene, and xylenes production to meet the market demands. The present invention provides a process for producing significant amounts of chemical grade BTX.
| benzene | toluene | ethylbenzene | p - xylene | m - xylene | o - xylene | |
|---|---|---|---|---|---|---|
| Molecular formula | C6H6 | C7H8 | C8H10 | C8H10 | C8H10 | C8H10 |
| Molecular mass, g · mol –1 | 78.12 | 92.15 | 106.17 | 106.17 | 106.17 | 106.17 |
| Boiling point, °C | 80.1 | 110.6 | 136.2 | 138.4 | 139.1 | 144.4 |
| Melting point, °C | 5.5 | – 95.0 | – 95.0 | 13.3 | – 47.9 | – 25.2 |