output. The liquid fuels produced through Sasol's GTL and CTL technologies are high-performance, low-emission products. The synthetic GTL-based diesel is an environmentally cleaner burning fuel as it leads to a reduction in carbon monoxide, hydrocarbon and particulate matter without compromising NOx emissions even when compared to European sulfur-free diesel. A high-temperature syngas conversion process is operated in Secunda in a series of 10 Sasol advanced Synthol (SASTM) reactors at high pressure with the aid of an iron-based Fischer–Tropsch process catalyst at about 350 °C to yield primarily C1 – C20 range hydrocarbons. The process also produces water and oxygenated hydrocarbons which are then purified and marketed. The C2 stream is split into ethylene and ethane. The ethane is further cracked to yield additional ethylene which are then converted into polyethylene for the polymer business. Propylene from Secunda and Sasolburg plants are also converted into high-value products such as polypropylene, butanol, butyl acrylate and ethyle acrylate. The acrylates are used to make superabsorbent polymers which are used in diapers. Through proprietary technology 1-hexene, 1-octene and 1-pentene are recovered from the oil stream. International customers use these as co-monomers for making speciality grade polymers. Some of the higher olefins (C11 – C12) are converted into detergent-range alcohols. A low-temperature syngas conversion process is operated in Sasolburg based on an iron-based catalyst in fixed-bed tubular and Sasol SPDTM processes to produce mainly linear hydrocarbon waxes and paraffins. The syngas (mixture of hydrogen and carbon monoxide) is also converted in methanol, butanol and ammonia. Ammonia is then converted into nitric acid and ammonium-based fertilizers and explosives. Tetramerization In 1997 Sasol Technology Research and Development began research on the selective trimerisation of ethylene to 1-hexene. This led to the development and patenting of 6 trimerisation catalyst systems. A groundbreaking innovation was made in 2002, with the discovery of a trimerisation catalyst that could make 1-octene in high selectivity. This was considered impossible by international experts in the field. Construction of this first-of-a-kind plant in Lake Charles, Louisiana, is under way. The ready for commissioning date is August 2013. Natref Refinery Sasol is also involved in conventional oil refinery. Incorporated on 8 December 1967, construction started on the Natref refinery in 1968 and commissioned in Sasolburg in 1971. It was built as a joint venture between the Industrial Development Corporation (IDC), National Iranian Oil Company and Compagnie Fransçaise de Petroles (Total) with financing by the Rembrandt