Total Pageviews

Saturday, October 17, 2020

Story of how South Africa developed Coal to Liquid Fuel (CTL) technology in 1950

Coal liquefaction is a process of converting coal into liquid hydrocarbons: liquid fuels and petrochemicals. This process is often known as "Coal to X", where X can be many different hydrocarbon-based products. However, the most common process chain is "Coal to Liquid Fuels" (CTL). Coal liquefaction was an important part of Adolf Hitler's four-year plan of 1936, and became an integral part of German industry during World War IIThe best-known CTL process is Fischer–Tropsch synthesis (FT), named after the inventors Franz Fischer and Hans Tropsch from the Kaiser Wilhelm Institute in the 1920s. In 1914, Friedrich Bergius, a teacher at the Technische Hochschule in Hanover, built a 40-litre vessel into which he put coal that had been dissolved in recycled oil, then added hydrogen. His catalyst was iron oxide. With the vessel loaded with these three ingredients, he raised its internal temperature to well above 400°C and increased the internal pressure up to 700 atmospheres (where one atmosphere is equal to air pressure at sea level). The result was petrol, diesel and recycle oil – and, in 1931, a share of the Nobel Prize for Chemistry with Carl Bosch, who had worked on developing high-pressure vessels for the Bergius and other synthesis processes. Fischer and Tropsch were granted a patent on their process in 1925.

Dr PN Lategan, working for the Transvaal Coal Owners’ Association in Johannesburg in the early 1920s wrote his doctoral thesis for the Imperial College of Science in London on The Low-Temperature Carbonisation of South African Coal. In the course of his research he visited Germany and, on his return home, tried to get some of the methods he had observed there to work. The next close investigation of the idea came from Dr F Meyer, working as technical adviser to the Department of Commerce and Industries. He wrote a White Paper for government in 1927, describing various oil-from-coal processes being used overseas and their potential for South Africa. Then in the 1930s, unreported by the press, a young student named Etienne Rousseau obtained his MSc degree from the oldest and most prestigious of the Afrikaans universities, Stellenbosch. Rousseau would become Sasol’s first managing director. In retrospect, that could seem almost inevitable, for the subject of his master’s thesis was The sulphur content of coals and oil shales, a highly relevant matter for anyone wanting to produce synthetic oil.

Read Sasol story `Mind over matter'.

No comments: