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TECHNOLOGY MILESTONES FROM THE CHEMIST’S VIEW I. ENERGY AND TRANSPORTATION. Chemists and chemical engineers have made many contributions to energy and transportation that allows us to power the lives we want to lead on land and in space.
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TECHNOLOGY MILESTONES FROM THE CHEMIST’S VIEWI. ENERGY AND TRANSPORTATION Chemists and chemical engineers have made many contributions to energy and transportation that allows us to power the lives we want to lead on land and in space. In the 19th century people heated their homes with wood or coal, used kerosene lanterns or candles for illumination, and traveled by railroad, steamboat, horse or on foot. As demands for energy in the last two centuries have increased, chemistry has developed and improved power sources, liquid fuel, batteries, and novel energy-conversion technologies. Advances in chemistry have also fueled the transportation revolution, contributing new and improved materials to automobiles, airplanes, space vehicles, and roadways. By extracting metals, minerals, and motor fuels from natural resources and by creating entirely new materials, their work as revolutionized our way of life of mankind. Chronology I.1. Energy Sources Utilization of coal as an energy source Petroleum exploration and production Nuclear energy Alternative energy sources I.2. Electrical Energy Storage and Portable Power Sources Single-use batteries Rechargeable batteries I.3. Materials for Roadways and Bridges Concrete Asphalt Metals and alloys Maintenance and repair technology I.4. Petrochemical Fuels Production of gasoline from crude oil Fuel additives Catalytic converters I.5. Automotive Vehicles Advanced materials for comfort and safety Plastic components Tire technology I.6. Aeronautics Hot-air balloons Helium Rocket fuel Construction materials for aircrafts and rockets
Technology Milestones in Energy and Transportation Chronology 1882 First coal-fired electric generating station supplies household electricity. 1884 The German Gottlieb Daimler builds the first gasoline-fueled, spark-ignited, piston-engine car. 1902 Asphalt pavement for roads is made from processing crude oil. 1913 Thermal cracking (breaking of long-chained molecules by heat) of hydrocarbons increases gasoline production from petroleum. 1921 Thomas Midgley, Jr. uses tetraethyl lead as an antiknock additive in gasoline. 1936The French Eugene Houdry develops the catalytic cracking of petroleum to produce high-octane gasoline. 1947 The American B. F. Goodrich firm introduces the first tubeless tires. 1949 Eveready Battery Co. miniaturizes the alkaline battery. 1954 First silicon-based solar battery is developed at Bell Labs. 1958 Boeing 707 jet airliners debut and begin to transform air transport. 1970s Unleaded fuels introduced; the phase-out of lead in gas begins. 1975 Catalytic converters are introduced in many automobiles. 1980-1990s Lithium-ion batteries are popular for cellular phones and laptop computers. 1981 The Columbia Space Shuttle becomes the world’s first reusable spacecraft.
I.1. Energy Sources Utilization of coal as an energy source Coal replaced wood as the principal source of energy in the United States by the 1890s. The first coal-fired power plant was built in 1882, generating steam that turned a generator to make electricity. In 1884, Charles Parsons developed the more efficient high-speed steam turbine. By the 1920s, pulverized coal increased efficiency and reduced the air need for combustion. The 1940 cyclone furnace used poorer-grade coals to produce less ash. Recently chemical technology has developed the combustion of culm (waste material from coal mining) to produce power and to decrease environmental load. Charles Parsons Steam turbine of Parsons (1907)
I.1. Energy Sources Petroleum exploration and production The 1901 discovery of the vast Spindletop oil field in Texas and the emergence of the automobile caused petroleum to surpass coal as the principal fuel source by 1951. The chemical technology of refining crude oil to separate its different chemical fractions has been continually improved, starting with simple atmospheric distillation and progressing to vacuum (reduced pressure) distillation to thermal cracking to the use of catalysts. For the primary crude oil recovery process, chemistry is most evident in diamond drilling bits, drilling muds, and oil-from-shale extraction using a combination of chemicals and steam. The secondary recovery processes include pumping high pressure gas (carbon dioxide) or water solutions into the earth.
I.1. Energy Sources Nuclear energy The first nuclear reactor was developed in 1942 for military use. After World War II., the diversion of nuclear technology to peaceful uses including the generation of electrical power plant began in 1951 with President Eisenhower’s Atoms for Peace program. Chemistry has played an internal part ever since, producing the radioactive materials used as fuel in the reactors, the reactor control rods that regulate the flow of neutrons from the radioactive decay, the reprocessing of the fuel rods after they lost their efficiency, waste-management, environmental protection, and minimizing radiation load of the citizens.
I.1. Energy Sources Alternative energy sources Unorthodox methods for power generation, such as wind, hydroelectric, and geothermal, account for less than one percent of the world’s total power generation, but they can play an important regional role, as determined by economics and availability. Through chemistry, solar panels for both thermal and photovoltaic generation, lightweight carbon fiber propellers for wind generation, concrete and metal turbines for hydroelectric plants, and corrosion-resistant materials for harnessing geothermal sources have all been developed. The first silicon-based solar battery (1954)
I.2. Electrical Energy Storage and Portable Power Sources Single-use batteries Electrical energy storage was developed by Alessandro Volta in the late 1700s, and chemistry has contributed to subsequent improvements in battery power. The 1890 carbon-zinc dry cell improved upon the earlier Leclanché ’wet-cell’ design. It was commercially produced for use in flashlights and it is still used today. In 1949, a new alkaline paste for the traditional battery enhanced lifetime and allowed miniaturization, and this alkaline battery quickly found many uses in portable electronic devices and cameras. Since then, newer battery developments have used silver oxide, mercuric oxide, or lithium. Carbon-zinc dry battery
I.2. Electrical Energy Storage and Portable Power Sources Rechargeable batteries The 1859 lead-acid rechargeable battery was an early commercial example of using a controlled chemical reaction to produce electricity. First improved in 1881 and continuously enhanced since, the lead-acid battery continues to be the dominant form of battery used in automobiles and trucks. The nickel-cadmium rechargeable battery, made originally in 1899, was too expensive to compete commercially. Latest developments have focused on lithium. After a failed attempt to use lithium metal in the 1980s, lithium-ion batteries are commonplace, finding applications in cellular phones and laptop computers.
I.3. Materials for Roadways and Bridges Concrete The massive U.S. interstate construction projects of the 1950s depended heavily on the strength and longevity of concrete on roads and bridges. Portland cement, first made in 1824 and patented as reinforced concrete by the French Joseph Monier in 1877, slow-sets due to a complex chemical reaction in which the cement paste fills the void around coarse and fine particulates and any reinforcements. Durability and strength depend on careful control of the cement manufacturing process, and adding different chemicals to the initial concrete mixture will reduce shrinkage and improve corrosion resistance.
I.3. Materials for Roadways and Bridges Asphalt Asphalt is a popular road construction material today because of its cost and performance advantages. Natural asphalt was discovered in 1595, but it was not bound with coal tar and used to pave roadways until 1902. Bitumen, the solid or semi-solid residue of the refinery process to make gasoline from petroleum, quickly replaced natural asphalt in paving. Recently, different synthetic polymers have improved performance and durability. Superpave (an acronym for Superior Performing Asphalt Pavements) is the latest technique for making superior asphalt to withstand adverse load and weather conditions.
I.3. Materials for Roadways and Bridges Metals and alloys Steel has become the primary structural material for bridges due to its light weight, strength, durability, ease of maintenance and construction, low erection costs, and resistance to natural disasters such as earthquakes. New high-performance steels introduced in the 1990s have superior strength and corrosion resistance. Another technology for protecting steel in bridge construction is a process known as metalizing where aluminum or zinc is sprayed onto a cleaned steel surface to form a 30-year protective coating.
I.3. Materials for Roadways and Bridges Maintenance and repair technique Road infrastructure must be maintained without significant deterioration in all types of weather and on a long timescale. Innovations in construction and maintenance materials have allowed longer intervals between the rebuilding of roads. Sealants for concrete, asphalt, and steel are important to prolonging road life. Other chemical and polymeric material function as binder addictives to enhance the performance of asphalt roadways, for example, styrene-butadiene-styrene results in less rutting and cracking in Europe.
I.4. Petrochemical Fuels Production of gasoline from crude oil To improve gasoline recovery from crude oil, refiners initially used heat to break down the larger molecules of the heavy oil fraction into the smaller ones found in gasoline, using a process called thermal cracking (1913). Since high temperatures also formed unwanted products, a vacuum distillation that operated at lower temperatures was used by 1928. Using an inert catalyst (catalytic cracking) rather then high temperature to achieve cracking was developed by Eugene Houdry (1936), was introduced commercially in 1937 and revolutionized the gasoline refining process. Eugene Houdry with the model of the catalytic converter
I.4. Petrochemical Fuels Fuel additives Thomas Midgley Jr. use tetraethyl lead as antiknock additive in gasoline (1921) Early automotive engines ‘knocked’ whenever poor quality gasoline was used. In 1921, tetraethyl lead was added to gasoline to make engines run smoother and quieter. By 1926, an octane rating was introduced to measure the quality of gasoline (compression tolerance). The use of lead additives was discontinued in the 1970s because of environmental concerns. Today, small amount of chemicals (alcohols, ethers) are added to gasoline to improve octane rating, enhance gasoline performance (metal deactivators), and reduce engine friction and wear to extend engine life (detergents). Seasonal chemical additives are used in some areas for geographical concerns, such as the addition of methanol to prevent freezing of fuel line.
I.4. Petrochemical Fuels Catalytic converters Two-stage catalytic converters were introduced in 1975 to control carbon monoxide and hydrocarbon emissions. Soon, a third stage was added to clean nitrogen oxides in the exhaust gas. Catalytic converters function by causing a series of chemical reactions to occur around the metal, usually platinum catalyst. Nitrogen oxides are converted into nitrogen and oxygen gases, carbon monoxide is converted into carbon dioxide, and the unburned hydrocarbons are converted to water and carbon dioxide. Three-stage catalytic converter
I.5. Automotive Vehicles Advanced materials for comfort and safety The automobile of 21st century bears little resemblance to its early predecessors in design, comfort, and safety for passengers. High-intensity discharge headlamps allow maximum nighttime illumination. Corrosion has been drastically reduced with special coatings and materials. Chemical refrigerants circulate in a closed-environment system. Automotive safety glass was introduced in 1914. Today’s special polymers coat glass to reduce weight and outside noise and to protect from glare and ultraviolet radiation. Safety innovations include polymer fibers in seat belt restraints (required in the 1960s) and in air bags (required in 1996).
I.5. Automotive Vehicles Plastic components Reducing weight in automobiles by transitioning from metal to plastics and identifying new high-performance materials are possible due to chemical achievements. After World War II., automobile manufacturers began using synthetic petroleum-based polymers for their toughness, hardness and weather resistance that are require for rigid structural components. After 1970s energy crisis, lightweight materials were sought to replace metals in various parts of the automobile. Design applications include: complex body shapes fabricated by injection molding, thermoplastic bumpers, polypropylene fibers that are colorfast and UV-stable, and special paints coatings, and adhesives. Polypropilene fibers
I.5. Automotive Vehicles Tire technology Natural rubber products appeared in the early 1800s, but were impractical due to softening or brittleness in hot or cold weather. An American inventor Charles Goodyear developed the vulcanization process for natural rubber in 1839, linking unsaturated bonds by sulfur. This basic process is still used with addition of chemical accelerants and stabilizers. By 1945, synthetic rubber was being commercially produced as a rubber substitute. As tire demand increased, improvements including using an inner tube to replace solid rubber tires, reinforcing with a natural or synthetic fabric cord for strength, and adding materials for reduced wear. Tubeless tires debuted later.
I.6. Aeronautics Hot-air balloons From 1783 when the first human flew in a balloon propelled by hot air rising an open fire, innovations in hot-air balloons have been revolutionary. Hot air was quickly replaced by hydrogen, which was easier to control. Hot-air ballooning has become a popular sport with more than 5000 hot-air balloon pilots in the United States. Chemistry has contributed the durable, inexpensive and heat-resistant nylon fabric and the liquid propane technology used for propulsion.
I.6. Aeronautics Helium Although hydrogen-filled balloons, such as the exploded Hindenburg (1937), had rigid structures, the flammability of hydrogen always posed a safety hazard. In 1905, two chemists discovered helium in a Kansas gas well, and this rare element was suddenly plentiful. During World War I., chemical technology extracted, stored, and shipped large quantities of helium, and helium-filled blimps in World War II. safely escorted troop and supply ships around submarines. In the 1950s, helium was useful as welding atmosphere during rocket construction and as the force needed to push the rocket’s fuel to the engines. The Hindenburg disaster (1937)
I.6. Aeronautics Rocket fuels From early test rockets first launched in the 1920s to communication satellites of the 1950s to the reusable Space Shuttle of the 1980s, the human expansion into space is an amazing engineering feat. Successful space travel depends on rockets possessing high-enough thrust velocity to overcome the gravitational force of the Earth. The first rocket was launched in 1926 using a liquid fuel of gasoline and liquid oxygen oxidizer. Subsequently, different fuels and oxidizers have been used in either solid or liquid form. The Space Shuttle uses liquid hydrogen as the fuel, but the launch engines use solid fuel of aluminum and ammonium perchlorate as the oxidizer with binder.
I.6. Aeronautics Construction materials for aircraft and rockets As aircraft design evolved from early wood and fabric to sophisticated engineered materials, chemical technology provided material that met design requirements. Different metal alloys using aluminum and titanium were developed to provide strength, light weight, high-temperature stability, and corrosion resistance to aircraft. Rockets have special material requirement because of the extreme conditions under which they operate. One example is a special tile in strategic locations protects the space shuttle (1980s) from high temperatures on reentry. After an exotic zirconium composite material was tried, the final tile design used silica fibers derived from common sand.