METHANOL: A SOURCE OF ENERGY
VEHICLES ARE FUELED WITH METHYL ALCOHOL IN MANY DEVELOPED NATIONS
SK ANSARI, SEEMA ANSARI
May 24 - 30, 2010
Methanol, also called methyl alcohol is in a liquid colorless, water soluble liquid with mild alcoholic odor. In 1920 wood was the only source to produce methanol which was needed in increasing quantities in the chemical industry.
During World War 1 methanol was derived from charcoal furnaces along with acetone and other essential chemicals. With Industrial revolution many other alternative process were made like coal and coke gasification that remained remarkable to produce Syngas to supply gas to the cities. Even the synthesis of Ammonia with Hydrogen from syngas and nitrogen from the air at a high temperature and pressure can be produced.
Fischer Tropsch in 1926 was the first to develop the process from the coal for the production of hydrocarbons, including that of methanol from syngas, a mixture of carbon monoxide and hydrogen was the basis for the petrochemicals industries. Fischer Tropsch (FT) gave birth to most of the industries like DuPont in the United States and BASF in Germany to produce to produce methanol and Ammonia.
Today, almost all methanol worldwide is produced from syngas. Virtually any hydrocarbon source (coal, petroleum, naphtha, coke, etc.) can be converted to methanol.
Pakistan's Thar Desert contains one of the largest coal reserves in the world, covering an area of 10,000 square kilometers. The Thar Coalfield, should it be developed, would yield over 200 billion ton of coal used to produce Methanol and Ammonia for the various petrochemical industries, particularly for blending methanol with gasoline to get rid oil import bill. Methanol can also be useful for power generation.
That coal development is possible only by inviting international chemicals companies and investors.
The concept of using an alcohol (methanol or ethanol) as a fuel is as old as the ICE (internal combustion engine) itself. Some of the ICE models, developed at the end of 19th Century by Nicholas Otto and others were virtually design to run on alcohol. By that time already, alcohol-powered engines had started to replace steam engines for farm machinery and train locomotives. Also used in automobiles, alcohol engines were advertised as less pollution than their gasoline counterparts. Most European countries with few or no oil resources were especially eager to develop ethanol as a fuel because it could be readily distilled from various domestic agriculture products.
Germany for example went from a production of almost 40 million liters of alcohol in 1887 to about 110 million liters in 1902. During the first decade of the 20th Century, many races were held between alcohol and gasoline powered automobiles, and there were lively debates as to determine which fuel gave the best performances. On an economic basis, however, ethanol could hardly compete with gasoline, especially in the United States which had plentiful petroleum resources at the time and a very powerful opponent.
The oil crises in 1970s and concern about the pollution make interest in alcohol grow. The large-scale development of alcohol fuel was most successful in Brazil, which was launched in 1975 under National Alcohol Program (PNA). More than 20 year, the production ethanol, mainly from sugar cane and its residues amounted to some 220,000 barrels of oil per day. This program PNA made millions of vehicles to run on alcohol.
In 1973 a paper in Science magazine noted addition of 10 per cent methanol to gasoline improved performance, gave better mileage, and reduced pollution. In 1975 VW began an extensive test, involving a fleet of 45 vehicles using 15 per cent blend of methanol in gasoline after minimal modification to existing engine.
Methanol acted as an octane booster, the methanol/gasoline blend delivering more power than pure gasoline. Even vehicle run on pure methanol were tested by VW in a cold start problems due to the lower volatility of methanol were successfully solved by using small amounts of additives such as butane and pentane.
Methanol significantly improved the cars' performance and considered a safer than gasoline. The 84 vehicle was tested over 2 million km, showed good fuel economy and engine durability which was comparable to that of gasoline vehicles. In United States it was concluded that, compared to gasoline engines, the use of neat methanol was found to be cheaper, increased the engine's lifespan and greatly decreased exhaust pollutants. In contrast to gasoline, which is a complex mixture containing many different hydrocarbons and some additives, methanol is a simple chemical and containing half the energy density of gasoline, which means that 2 L of methanol contains the same energy as 1 L of gasoline.
Efficiency also increases by methanol's higher "flame speed" which enables a faster and more complete fuel combustion in the cylinders. Methanol also has a latent heat of vaporization which is about 3.7 times higher than gasoline, so that methanol can absorb a much larger amount of heat when passing from the liquid to gaseous state.
High heat of latent for methanol helps to remove heat from the engine so that it may be possible to use air cooled radiators instead of heavier, water cooled systems. Methanol as a fuel will be better for a smaller car as it does not require a large water cooling system. Methanol vehicles have low overall emissions of air pollutants such as hydrocarbons. With pure methanol, cold start problems can occur due to its less volatility compounds.
ADVANCED METHANOL POWERED VEHICLES
Methanol or its derivatives can already be used as substitutes for gasoline and diesel fuel in today's ICE-powered cars, with only minor modifications to existing engines and fuel systems. ICE is a much-proven and reliable technology, which has been continuously improved and perfected since its invention over a hundred year ago. Fuel economy compared to generated power is now better and emission lower than ever before. Hybrid cars, combining an ICE with an electric motor are commercialised by a growing number of companies (Toyota, Honda, Ford, etc) and can reduce even further fuel consumption and emissions. In these vehicles too, gasoline and diesel fuel can be easily substituted by methanol or its derivatives. Their use on a large scale is realisable in the relative short term. In the foreseeable future, however, in order to further increase efficiency and lower emissions, fuel cell technology will be the best alternative to ICEs in the transportation field. Much effort and financial resources are currently being invested by major motor car manufacturers and governments to make fuel cell vehicles (FCV) an affordable and viable option for consumers in the foreseeable future.
FCVs promise to be much quieter, cleaner and to require less maintenance than ICE because of fewer moving parts.
METHANOL POWERED BATTERIES
Toshiba has developed a promising DMFC (Direct Methanol Fuel Cell) for laptop computers. The stack has an average of 12 W and may be continuously used for 5 h with a 50-mL methanol storage cartridge. To minimize the size of cartridge, the cell collects output water for recombination with methanol. Sensors are hooked up directly to the PC to tell users when cartridge needs replacing. NEC has developed similar stacks and, within the next few years, anticipates the stack to have a 40-h operation time.
A fuel cell is a small power generator that converts the chemical energy of fuel, such as methanol, into electric energy. Unlike batteries, which require recharging, fuel cells can continuously producing electricity as long as there is a constant fuel supply (methanol). DMFC use methanol as fuel and do not change the chemical structure of methanol by subtracting hydrogen when feeding the fuel into the cell, thus sending methanol "directly" into the cell. Direct Methanol Fuel Cell (DMFC) can provide a new energy concept for personal electronic devices such as notebook PCs, cellular phones or wearable electronics devices like audio players and headsets.
Both stationary and portable DMFC stacks are now available for consumer purchase. For instance, The Fuel Cell Store offers its SFA A25 Smart Fuel Cell, capable of 25W continuous output, and can cover four days worth of energy demand using only 2 kg of fuel (methanol). A large 50W model is also available.
The Methanol Fuel Cell continuously recharges the battery, which powers the electric motor. Regenerative braking (powered developed by the engine) technology also captures the energy usually dissipated during braking to provide additional battery charging.
Nissan is testing a fuel cell/battery hybrid vehicle first shown in Japan in May 2000. The car, based on the Xterra SUV, features a PEM fuel cell using a methanol-reformer and lithium-ion batteries. The vehicle is able to switch between fuel cell power and battery power while in operation. Nissan and Suzuki have joined a government-sponsored project to develop DMFCs for vehicles that is expected to result in a prototype vehicle by 2003.
It is projected that the total number of vehicles worldwide will increase to one billion by 2020. The introduction of large numbers of low-emission, energy-efficient MFCVs is not only needed, but well within reach. There have been several attempts to estimate the future market penetration of FCVs. The DOE has estimated that FCVs will account for 1.3 percent of the new car market in 2010, and 8.24 percent in 2020. The Japanese Institute of Energy Economics estimates that the share of new car sales for FCVs (Fuel Cell Vehicles) in Japan will increase rapidly from 0.1 percent in 2010 to 33.5 percent in 2020.
DIRECT METHANOL FUEL CELL TECHNOLOGY
Direct methanol fuel cells employ a polymer membrane as an electrolyte. The system is a variant of the polymer electrolyte membrane (PEM) cell. However, the catalyst on the DMFC anode draws hydrogen from liquid methanol. This action eliminates the need for a fuel reformer and allows pure methanol to be used as a fuel.
The pure methanol is mixed with steam and fed directly in to the cell at the anode. Here, the methanol is converted to carbon dioxide and hydrogen ions. The electrons are then pushed round an external circuit to produce electricity (before returning to the cathode) whilst the hydrogen protons pass across the electrolyte to the cathode. At the cathode, the protons and electrons combine with oxygen to produce water.
The operating temperature for DMFCs is in the range of 60-1300C but is typically around 1200C, producing an efficiency of about 40 per cent. DMFC units are best suited to portable applications and have been used in a wide variety of portable electronic products such as mobile phones and laptop computers. Due to the low temperature conversion of methanol to hydrogen and carbon dioxide the DMFC system requires a noble metal catalyst. The cost associated with this catalyst is outweighed by the ability of the unit to function without a reforming unit. By using liquid methanol as a fuel some of the storage problems related to hydrogen are eliminated. In addition, liquid methanol is often considered to be easier to transport and supply to the public using current infrastructure.
THE CURRENT DMFC MARKET
DMFC systems are used to power portable applications and in some niche transport sectors such as marine and submarine vessels, scooters and motorbikes and as auxiliary power units.
DMFC technology is particularly suited to portable applications thanks to the fact that pure methanol can be used as a fuel and the need for a fuel reformer is eliminated. Since 2003, there has been a significant year-on-year increase in the number of units installed. There are a number of reasons behind such growth trends. Decreasing barriers to adoption, specifically cost, has enabled the increased production of DMFC units. In addition, companies are working hard to ensure the technology meets customer requirements rather than consumers having to meet the technology requirements. This is of particular importance when working in the consumer portable electronics sector.
In terms of where DMFC units are installed across the globe, North America accounts for around 44 per cent of the geographical split. Europe is the second largest global region in terms of DMFC activity but is closely followed by Japan and the Rest of the World countries. It is perhaps unsurprising that North America (including Canada) and Europe together account for the majority of global share of DMFC activity as historically this is where most of the investment for research and development has been made. The military accounts for a significant part of DMFC development programmes for portable electronic products. Military investment for the development of fuel cell powered equipment remains a high priority, particularly in North America and Europe and this can go some way to explaining why these regions dominate DMFC activity on a global scale. In addition, consumers in these two regions tend to be affluent and can therefore afford to purchase the newest technological products. This consumer pull for top end products might also explain why DMFC activity in North America and Europe is high.
The fuel cell is designed to power remote equipment and applications in the military field. The Fuel Cell based on a Lightweight Portable Power System for Battlefield Airmen and also developing a 250W fuel cell for the Army Operational in the remote areas.
In summary, whilst there are still some hurdles to be overcome for DMFC technology (including unit size, weight, power and cost, shipping and insurance delays) there are many positive aspects connected with DMFC.
DMFC remains to be the technology of choice in a sector that will one day be fully commercialised. There is a sufficiently strong technology pull from both the public sector and the military where sufficient funding can be provided for development programmes to continue with the development of DMFC solutions for powering portable electronic products. In addition, codes and standards and other regulations are being put in place to support the widespread adoption of DMFC technology. Together, these observations suggest that the future prospects for DMFC technology are very promising.
OTHER ASPECTS OF METHANOL UTILISATION
Methanol is suggested principally as a fuel for automobiles, also it could be used advantageously in most other fuel application. Methanol is safe, clean fuel for home heating and can be burned in power plants to generate electricity without pollution the atmosphere. A pilot plant was operated to run full scale power boiler demonstrations with methanol instead of furnace oil or natural gas. The following result was revealed.
(i) No particulates were released from the stack.
(ii) No sulphur compounds were emitted.
Methanol is one of the few known fuels suited to power generation.
Up to 15 percent methanol can be added to gasoline in current cars, without adjustment of the engine, and with noticeable improvement in exhaust quality, economy and performance.
Methanol prevents knocking or "pinging" common with unleaded fuels, and it alleviates "running on" or "dieseling" when the ignition is switched off. These practical and well-documented qualities, added to the virtue of reducing national fuel dependence on the Organization of Petroleum Exporting Countries, have made methanol the leading candidate for the motor fuel of the immediate as well as the foreseeable future.
Methanol blends have been tested in many racing automobiles in the past. A summary of performance after testing series of cars was:
- fuel economy increased by 5 to 13 percent;
- carbon monoxide emissions decreased by 14 to 72 percent;
- exhaust temperatures decreased by 1 to 9 percent;
- acceleration increased up to 7 percent.
A car operated with unleaded gasoline sometimes knocks badly on acceleration. But when a gallon of methanol is added to nine gallons of gasoline in the tank, the knocking disappears.
Gasoline composes of relatively high molecular weight hydrocarbons compared to methanol and ethanol. Gasoline has a wide, continuous boiling range while methanol and ethanol have single boiling points in the middle of the gasoline boiling point range.
In the coldest weather typical of that experienced in parts of New York State, use of M70 and E70 (i.e. 30 volume percent gasoline) may be warranted to prevent cold-start problems.
One gallon of M85 has only 56 per cent of the energy of one gallon of gasoline, while E85 has 71 per cent. This means that it takes 1.75 gallons of M85 to equal one gallon of gasoline, and 1.4 gallons of E85 to equal one gallon of gasoline. Methanol and fuel-ethanol are more corrosive than gasoline and require that minor changes be made in gasoline fuel system materials to be compatible.
CHINA TAKES GOLD IN METHANOL FUEL
In 2007, China firmly established itself as the driver of the global methanol industry. The country became the world's largest methanol producer and consumer. China also leads the world in the use of methanol as an alternative transportation fuel blending nearly one billion gallons of methanol in gasoline. Taxi and bus fleets are running on high methanol blends (M-85 to M-100), and retail pumps sell low level blends (M-15 or less) in many parts of the country. China has already manufactured automobiles with methanol engines. The Cherry automobile company tried ten methanol cars earlier this year. Shanghai Maple plans to make 50,000 methanol cars.
The methanol fuel has been spread in Shanxi for 3 years. About 100,000 tons of the methanol fuel has been applied to about 5 million automobiles. Blended fuel is a cheaper and an environment-friendly alternative to ordinary gasoline, market sources said, but the government ultimately leaves it to car owners to decide whether or not to make the switch.