[CAIRO] Researchers at Egypt’s National Research Centre have produced a biofuel suitable for aeroplanes after successful semi-industrial experiments conducted last December.
The centre was officially commissioned by the Egyptian Ministry of Civil Aviation to find a local biofuel to power aircrafts. This was to support the implementation of the International Air Transport Association plan, aiming to halve carbon dioxide emissions caused by aviation companies by 2050. Commercial aviation contributes about 2 per cent of global carbon emissions annually.
Gizine El Diwani, professor at the centre’s chemical engineering and semi-industrial experiments department, says it all started with the production of a biofuel for cars. The researchers made biodiesel from the seeds of the jatropha tree — the seeds’ oil content is between 20-25 per cent. The oil can be easily extracted using organic solvents such as hexane, according to El Diwani.
“Globally, the lowest price of biofuel is 90 per cent higher than that of the average fuel; this is due to the high cost of the materials needed for the manufacture of biofuel.”
Khaled Fouad, Zagazig University in Egypt
Because the properties of jatropha oil differ from those of traditional engine oil — in terms of viscosity, density and degree of combustion — it has to go through a number of fairly simple chemical processes to be adapted for use in running engines.
At this stage, the fuel is suitable for car engines. To be suitable for jet engines, it should be able to resist freezing until at least minus 45 degrees Celsius. The research team sought to resolve this at a later stage in the fuel’s development.
El Diwani explains: “We managed to improve the freezing point of jatropha biofuel through a thermal cracking process, using thermal stimuli at a high temperature and pressure to bring the oil [temperature down] to minus 40 degrees [Celsius] without [it] freezing. Then, we were able to reach minus 45 degrees by introducing some [chemical] additives.”
El Diwani adds that Egypt has successfully cultivated vast land areas with the jatropha tree, in an area of the Upper Egypt desert estimated at around 1000 acres. The success of biofuel production experiments is expected to encourage the research team to increase the area reserved for growing the tree.
Khaled Fouad, a researcher in the field of aeronautical engineering at Zagazig University in Egypt, sees a fundamental advantage in the production of biofuels from jatropha seed oil. “It is a non-edible tree for humans and animals, which grows in sandy desert soil and gets irrigated by sewage water — making it a unique source of biofuels.”
However, Fouad pointed to a serious challenge in the high cost of production, which he attributes to the use of additives to lower the freezing point. “Globally, the lowest price of biofuel is 90 per cent higher than that of the average fuel; this is due to the high cost of the materials needed for the manufacture of biofuel,” he said.
Another semi-industrial experiment on the biofuel will be conducted after introducing this type of cracking. The team hopes to complete all industrial experiments and begin to use locally-manufactured biofuel in aeroplanes by the end of 2017, according to El Diwani.