Science & Technology Quiz: Biofuels and Ethanol Blending

The correct answer is B, ethyl alcohol, C2H5OH. Ethanol is the two carbon alcohol obtained by the fermentation of sugars by yeast, and it is the alcohol blended into petrol under the Ethanol Blended Petrol programme. Option A is wrong because methyl alcohol or methanol is a different, single carbon alcohol; it is highly poisonous and is the subject of a separate methanol blending programme, not the ethanol one. Option C is wrong because glycerol is a three carbon trihydric alcohol and in this chapter appears as the by-product of biodiesel manufacture, not as a fuel blend. Option D is wrong because acetic acid is a carboxylic acid, the acid of vinegar, formed when ethanol is oxidised; it is not a fuel. Remember that ethanol also raises the octane number of petrol.

The correct answer is C, paddy straw. Second generation biofuels are made from lignocellulosic biomass that is not food, such as paddy straw, wheat straw, bagasse, cotton stalk and municipal solid waste; the cellulose must first be broken down into fermentable sugars, which makes the process costlier and earns these fuels the name advanced biofuels. Options A and B are wrong because sugarcane juice and maize grain are food or food crop materials and yield first generation ethanol, the ordinary kind. Option D is wrong because edible mustard oil would give first generation biodiesel, and Indian policy avoids edible oils altogether and looks to non-edible seeds like Jatropha instead. India built its first commercial second generation ethanol plant, running on paddy straw, at Panipat in Haryana.

The correct answer is A, compressed bio-gas. SATAT stands for Sustainable Alternative Towards Affordable Transportation and was launched in October 2018 by the Ministry of Petroleum and Natural Gas; under it the oil marketing companies invite entrepreneurs to set up compressed bio-gas plants from agricultural residue, cattle dung and municipal waste and offer to buy the gas for sale at their retail outlets. Option B is wrong because rooftop solar is promoted through separate schemes of the Ministry of New and Renewable Energy. Option C is wrong because nuclear fuel reprocessing is the business of the Department of Atomic Energy and has no connection with biomass. Option D is wrong because green hydrogen has its own National Green Hydrogen Mission. Compressed bio-gas is over ninety per cent methane.

The correct answer is C, methane. Biogas is produced by the anaerobic digestion of organic matter, and methane is its largest component, roughly half to three quarters of the gas by volume; this is what makes biogas combustible. Option A is wrong because carbon dioxide is the second largest component, usually a quarter to a half, and it does not burn; it is scrubbed out when raw biogas is upgraded to compressed bio-gas. Option B is wrong because hydrogen sulphide is present only in traces, and it is removed because it is corrosive and foul smelling. Option D is wrong because carbon monoxide is a product of incomplete combustion of fuels and is not a normal constituent of biogas at all. Upgraded compressed bio-gas is over ninety per cent methane.

The correct answer is A, transesterification. In transesterification a vegetable oil or animal fat is made to react with methanol or ethanol in the presence of an alkaline catalyst such as potassium hydroxide, giving fatty acid methyl esters, which are biodiesel, and glycerol as the by-product. Option B is wrong because fractional distillation is how crude petroleum is separated into petrol, kerosene and diesel; it separates an existing mixture instead of making a new ester. Option C is wrong because hydrogenation adds hydrogen across double bonds and is the process that turns liquid oils into vanaspati. Option D is wrong because fermentation is the anaerobic action of yeast on sugars, which is how ethanol and not biodiesel is produced. Pure biodiesel is designated B100, a five per cent blend is B5, and the alkaline catalyst commonly used in the reaction is potassium hydroxide or sodium hydroxide.

The correct answer is B, biodiesel. Jatropha curcas yields a non-edible oil seed, and because India cannot spare edible oil for fuel, the National Policy on Biofuels looks to non-edible oils such as Jatropha and Pongamia pinnata, or karanja, along with used cooking oil and animal tallow, as feedstock for biodiesel. Option A is wrong because bioethanol comes from sugar and starch materials, molasses, sugarcane juice, maize and damaged grain, through fermentation. Option C is wrong because biogas is produced by the anaerobic digestion of wet organic waste such as cattle dung, not by pressing an oilseed. Option D is wrong because biochar is the charcoal-like solid left when biomass is heated without air and is used as a soil amendment, not as a liquid fuel.

The correct answer is A, 20 per cent ethanol. In this notation the letter E stands for ethanol and the number gives its percentage by volume in the blend, so E20 is one fifth ethanol and four fifths petrol, while E10 is a tenth ethanol and E85 is a high blend meant for flex fuel vehicles. Option B is wrong because biodiesel blends are written with the letter B, as in B5 and B100, and are blended with diesel rather than petrol. Option C is wrong because methanol blends are written with the letter M, as in M15, and form a separate programme. Option D is wrong because compressed bio-gas is a gaseous fuel used in place of compressed natural gas and is not blended into petrol at all.

The correct answer is B, advance the 20 per cent ethanol blending target to 2025-26. The National Policy on Biofuels of 2018 had set 2030 as the year for twenty per cent ethanol in petrol; the 2022 amendment brought that forward to the ethanol supply year 2025-26, and also widened the permitted feedstock and allowed the production of biofuels in special economic zones for export. Option A is wrong because molasses remains the mainstay feedstock for Indian ethanol and was never banned. Option C is wrong because the biodiesel blending target of five per cent by 2030 continues under the same policy. Option D is wrong because the policy is administered by the Ministry of Petroleum and Natural Gas, which was not changed by the amendment. Remember also that an ethanol supply year runs from December to November.

The correct answer is B, second generation ethanol bio-refineries. The Pradhan Mantri JI-VAN Yojana was approved in 2019 to give viability gap funding to commercial and demonstration projects that make ethanol from lignocellulosic biomass such as paddy straw and bagasse, since such advanced plants cost far more than ordinary molasses distilleries. Option A is wrong because solar pumps and panels for farmers come under the PM-KUSUM scheme. Option C is wrong because electric buses are supported through the FAME and later electric mobility schemes of the Ministry of Heavy Industries. Option D is wrong because rural cooking gas connections were given under the Pradhan Mantri Ujjwala Yojana. India built its first such commercial paddy straw plant at Panipat in Haryana, and the full name of the scheme expands to Jaiv Indhan Vatavaran Anukool Fasal Awashesh Nivaran, which itself points at crop residue.

The correct answer is B, the G20 summit in New Delhi. The Global Biofuels Alliance was launched in September 2023 during the G20 summit held in New Delhi under India’s presidency, with India, the United States and Brazil among its founding members, the three being the largest producers and users of ethanol. Its purpose is to help member countries build biofuel markets, trade and technology. Option A is wrong because the BRICS summit at Johannesburg in 2023 is remembered for the admission of new members, not for this alliance. Option C is wrong because the climate conference at Dubai that year produced the first global stocktake. Option D is wrong because Davos is an annual business gathering and does not launch intergovernmental alliances of this kind.

The correct answer is A, Swachh Bharat Mission Grameen. GOBARdhan, which expands to Galvanizing Organic Bio-Agro Resources Dhan, was launched in 2018 by the Department of Drinking Water and Sanitation in the Ministry of Jal Shakti as a part of the rural sanitation mission, because turning dung and farm waste into biogas is both a waste management and a clean fuel measure. Option B is wrong because the Fasal Bima Yojana is a crop insurance scheme. Option C is wrong because the National Clean Air Programme sets city-wise targets for cutting particulate pollution and is run by the environment ministry. Option D is wrong because the Gram Jyoti Yojana dealt with rural electrification and feeder separation, not with biogas. The petroleum ministry runs a parallel scheme for the same fuel, SATAT, on the commercial transport side.

The correct answer is B, Brazil. After the oil shock of 1973 Brazil launched the Proalcool or National Alcohol Programme in 1975, requiring ethanol made from its abundant sugarcane to be blended with petrol and later building cars that could run on pure ethanol; it is the oldest and best known national biofuel programme. Option A is wrong because the United States became the largest ethanol producer much later, using maize, and its blending mandates date from the 2000s. Option C is wrong because China came to fuel ethanol later still and in smaller volumes. Option D is wrong because Germany is associated with biodiesel from rapeseed rather than with a pioneering ethanol programme. India, the United States and Brazil founded the Global Biofuels Alliance in 2023.