Applications
Like other LAO (Linear Alpha Olephins), Hexene-1 or 1-Hexene is used as co-monomer for polyolefins manufacturing. It is used as enhancer to strengthen the bonds in polyolefin chains for production of various grades of polyethyelene. The primary use of 1-hexene is as a comonomer in production of polyethene. High density polyethene (HDPE) and linear low density polyethene (LLDPE) use approximately 2-4% and 8-10% of comonomers. Another significant use of 1-hexene is the production of linear aldehyde via hydroformylation (oxo synthesis) for later production of the short-chain fatty acid heptanoic acid.
Chemical Information and Process Technology
What is Hexene-1? Hexene-1 is an alkene, a type of Linear Alpha Olefins (LAO) with chemical formula of C6H12. An alpha olefin is when the double bond is located at primary position or also called the alpha position which provides higher reactivity for chemical reactions which is a crucial chemical property.
Process Synthesis Industrially, 1-hexene is commonly manufactured by two main routes: oligomerization of ethene and by Fischer-Tropsch synthesis followed by purification. Another route to 1-hexene, used commercially on small scale, is dehydration of alcohols. Prior to the 1970's 1-hexene was also manufactured by the thermal cracking of waxes. Linear internal hexenes were manufactured by chlorination/dehydrochlorination of linear paraffins.
There are five commercial processes which oligomerize ethene to 1-hexene. Four of these processes produce 1-hexene as a part of a wide distribution of alpha-olefins. Typically, 1-hexene content ranges from about twenty percent distribution in the Ethyl (Innovene) process, whereas only twelve percent of distribution in the Gulf (CP Chemicals) and Idemitsu processes.
The only commercial process to isolate 1-hexene from a wide mixture of C6 hydrocarbons is practiced by Sasol Ltd., a South African oil and gas and petrochemical company. Sasol commercially employs Fischer-Tropsch synthesis to make fuels from synthesis gas derived from coal. The synthesis recovers 1-hexene from the afformentioned fuel streams, where the initial 1-hexene concentration cut may be 60% in a narrow distillation, with the remainder being vinylidenes, linear and branched internal olefins, linear and branched paraffins, alcohols, aldehydes, carboxylic acids and aromatic compounds.
Synthesis of 1-hexene as a part of multi-product ethene oligomerization process or a Fischer-Tropsch process is covered in an article on
Linear alpha olefins. One process, the Phillips ethene trimerization process, produces only 1-hexene.
Licensing and Technology Licensors
One of the technology provider for Hexene-1 is ABB Lummus Global and China Petroleum & Chemical Corp. (SINOPEC Corp.) who both have signed a cooperation agreement creating a strategic alliance to develop and market new recovery technology for ethylene plants. The collaboration merges the extensive capabilities and experiences of both companies in the area of recovery technology. ABB Lummus Global and SINOPEC Corp. will license the technology worldwide, for both grassroots and revamp projects through ABB Lummus Global. ABB Lummus Global will contribute front-end and back-end selective hydrogenation utilizing CDHydro(r) hydrogenation technology, developed by its joint venture company CDTECH; tertiary refrigeration; its low pressure chilling train; and Olefins Conversion Technology (OCT) to self-metathesize butenes to produce hexene-1. SINOPEC Corp.'s contributions include condensing fractionation towers, high capacity trays, high flux tubes, and low temperature arsenic removal from liquid feeds.
