Soon, aircraft will fly using biofuel derived from jatropha oil, thanks to the efforts of the Indian Institute of Petroleum (IIP) that successfully converted jatropha oil into jet fuel through research that can reduce India’s dependency on oil producing countries for jet fuel in the near future. It may also prove to be a revolutionary step in the quest for alternative fuels.
The research, which started around five-year ago, bore fruits in late 2010 when scientists efficiently converted jatropha oil into jet fuel at IIP lab. In 2011, the achievement got international recognition after American Standard Testing Method (ASTM) approved this biojet fuel for commercial application in aircraft.
Principal scientist Dr Anil Sinha, the man behind the research, said, “ASTM in its approval recommended that upto 50 per cent blend of biojet fuel with normal fuel can be used for commercial applications in aircrafts. This endorsement infused fresh energy in the team since its efforts got international recognition, and it went ahead with the project with a fresh zeal.”
After the landmark achievement, a large pilot plant with 20 litre per day production capacity of Bio-Jet fuel was set up at IIP. Subsequently, conversion of jatropha oil into bio jetfuel started. Now, the plant produces enough fuel for testing in aircraft engines. The process to check the viability of its production for commercial use is also on.
Enthused with this achievement, Sinha is confident that bulk production will bring down its cost. “At present, per litre bio jet fuel costs Rs 100. But, initial test has shown very positive results. So we strongly believe that bulk production will bring down its cost tremendously. Jatropha oil, purchased from Udaipur, is converted into bio jet fuel,” Dr Sinha said.
Sinha also highlighted difficulty in developing alternative fuels. “Jet fuel must meet very stringent international specifications, due to which it is much more difficult to develop an alternative fuel for aviation than for automobile applications,” Sinha said.
He claims, “Bio jet fuels derived from jatropha oil is suitable to use in aircraft. CSIR-IIP is the first institute in India to produce 300 litres of high quality biojet fuel from jatropha curcas oil and approximately 130 litres was supplied to aircraft engine manufacturer Pratt & Whitney, Canada and another 70 litres to IOCl for blending and further supplying to IISc Banglore for engine tests.”
He also claims that the fuel has been tested by both Indian Oil Corporation and HPCl and has been found to meet all specifications as per ASTM D 1655 and ASTM D7566 for Jet A-1 fuel (ATF).
Biojet fuel is in high demand for several reasons. Firstly, it provides security to the airlines against fluctuation in ATF (Aviation Turbine Fuels) prices. Secondly, ATF availability is expected to reduce gradually in the near future. Also it can be used as a drop-in fuel after approval by ASTM to use upto 50 per cent blend of biojet fuels with normal fuels (ASTM D7566).”
Sinha defines this research as innovative since it involves single-step process that is all the reactions can be carried out by a single catalyst for conversion of plant derived non-edible, waste, low cost oils to produce drop-in biofuel for air-transport purposes.
Sinha further adds plant derived oils (soya, jatropha, karanj, algal) and waste cooking oils are deoxygenated, selectively cracked and isomerized over a single catalyst to produce aviation fuel with 35-55% yield and with properties and compositions exactly same as those required for aviation fuel.
Also the biojet fuel produced contains 10-20 % aromatics which is an added advantage in the process and reduces any addition of costly aromatic additives.
He says, “The environmentally polluting SOx from the biojet is also 10-20 times lower as compared to that from petroleum based aviation fuel. In addition to biojet, the process also produces gasoline and diesel fuel cuts which can also be blended in the fuel pool.”
Sinha says, “Hydroprocessing catalysts supported on mesoporous zeolites, silica-alumina and alumina supports were used to convert triglycerides to obtain pure hydrocarbons, for biojet fuel production from jatropha oil. The desired products were obtained when using highly acidic supports in a single step.”
“But, the long-chain hydrocarbons produced from hydrotreating reactions (over alumina supported catalyst) are selectively hydrocracked and hydroisomerized in the second step using suitably designed catalysts to give products that include jet fuel range hydrocarbons,” he added.
The European Union has imposed carbon tax on airlines and others would follow the same. Since The International Air Transport Association (IATA), which represents 93 percent of the world’s carriers aims 10 percent of its fuel from renewable sources by 2017 and Airbus expects 30% Biojet blend (by 2030). With all these projections we can say if such renewable fuels would be commercialized they have immense potential in aviation sector.