Transcript: Catalysis: Technology for a Clean Environment
1993
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00:00:00 In a galaxy far beyond home or planet
00:00:25 Life
00:00:29 Death
00:00:35 Change
00:00:42 Regeneration
00:00:45 These are all parts of nature's cycle
00:00:48 The changes in nature that we see with our eyes happen only because of changes we cannot see
00:01:03 Changes that occur due to the reaction of molecules, the tiny particles at nature's core
00:01:10 Many of these reactions could not occur though were it not for enzymes
00:01:15 A special kind of molecule that serves as a catalyst or facilitator of chemical change
00:01:22 These enzymatic catalysts help along organic decomposition in our forests
00:01:27 A process essential to the regeneration of trees and other vegetation
00:01:32 Enzymatic catalysts also break down biological waste as it floats down creeks and rivers purifying water in the process
00:01:48 Nature
00:01:56 More recently we have learned to imitate nature by creating and changing molecules to produce new kinds of materials that we rely upon for our comfort and survival
00:02:08 For example the fabric in this parka with its ability to breathe and yet keep the wearer dry
00:02:16 Could not have been made without the knowledge we have gained about how molecules react with one another
00:02:22 And the critical role catalysts can play in these reactions
00:02:26 Science, technology, our standard of life, all in some way rely on our knowledge of how to guide chemical changes to a desired end
00:02:44 But can we produce the things we want and need and still keep our air pure and our water clean?
00:02:53 As we shall see the answer to this important question lies with the ability of today's new catalysts to clean up toxic waste
00:03:01 To reduce emissions using new catalytic converters
00:03:05 And to protect the global environment by eliminating harmful pollutants altogether
00:03:23 So what is a catalyst and how does it work?
00:03:26 A catalyst is a substance that reacts with say two molecules
00:03:31 Under the influence of the catalyst these two molecules form a new desired molecule which is then released from the catalyst
00:03:39 The catalyst is now free to react with two more molecules and to repeat the same reaction again and again without itself being consumed in the reaction
00:03:49 In other words the catalyst remains essentially unchanged throughout the process
00:03:55 In essence a catalyst acts like an engine one which produces a product molecule upon each revolution
00:04:01 The size of this engine is comparable to that of a molecule
00:04:05 However despite its minute size a catalyst like a properly running engine turns over regularly making a new molecule each time it turns over
00:04:14 Typically a catalyst can turn over a hundred molecules per minute and a catalyst can produce millions of new molecules in this manner before it dies
00:04:25 Catalysts come in many different forms
00:04:28 They can exist as powders, take the form of liquids or various shapes of pellets
00:04:38 These catalysts are embedded or coated on the surfaces of solids such as ceramics, metals or carbon
00:04:45 The active components of these catalysts can vary from materials such as enzymes to finely divided metals like platinum or nickel
00:04:55 Besides speed and long life the beauty of a catalyst is that it makes the desired product without creating unwanted and often toxic byproducts
00:05:05 This property called selectivity is vitally important in the goal of manufacturing without polluting
00:05:16 Little wonder then that catalysts with their speed, durability and selectivity are revolutionizing the way chemistry is being done
00:05:26 Dr. James Cusumano is a chemist who has been working with a company specializing in designing catalysts
00:05:34 All of nature whether it be plants, animals or human beings if we look at the molecular structure can have either a left-handed form or a right-handed form
00:05:43 Let's take the human being and the human brain
00:05:46 The molecules in our brain can be either left-handed or right-handed
00:05:50 Now if we want to design a pharmaceutical that will have an appropriate therapeutic response in the brain
00:05:56 We have to make the appropriate molecule either left or right so it fits like a left hand into a left glove
00:06:03 The pharmaceutical L-DOPA which is used to treat Parkinson's disease and ameliorate the symptoms of Parkinson's disease is prepared by a catalytic process
00:06:12 That catalyst has been designed to make only L the left-handed DOPA form
00:06:18 The R form or the right-handed form is totally inactive
00:06:21 Now this selectivity property applies pervasively throughout industry
00:06:26 If we want to make the appropriate fuel molecules that are clean, appropriate fiber molecules or other pharmaceuticals
00:06:34 We can design catalysts at the molecular level to make only the form which is appropriate
00:06:40 And minimize and in some cases eliminate totally other byproducts which may be toxic to the environment
00:06:48 The development of catalysts began early in this century when the growing industrial economy found itself in need of them
00:06:56 The German scientist Fritz Haber discovered that ammonia, the main component in certain essential fertilizers
00:07:04 Could be made more quickly and economically by taking hydrogen and nitrogen
00:07:08 And passing them over the surface of a catalyst that used iron as its base
00:07:14 This innovation dramatically increased the availability of ammonia-based fertilizers
00:07:19 Thus making possible significantly greater yields of food crops
00:07:26 Today, technologies based on catalysis give us the means to manufacture many things we take for granted
00:07:33 The fabric in the clothes we wear, the plastics out of which so much is made
00:07:38 Including those credit cards we cannot seem to do without
00:07:42 The soles of the shoes that take us on our rounds of business or pleasure
00:07:46 Catalysis and engineering have become an essential part of our lives
00:07:51 And will play an even more important role in the future
00:07:54 A future built on the past and aimed at improving the quality of our lives and our society
00:08:01 And not at the expense of our environment
00:08:12 The End
00:08:25 Change
00:08:26 Progress
00:08:28 Call it what you will
00:08:30 Can we slow it down?
00:08:32 Stop it?
00:08:33 No
00:08:35 No more than we can stop the drive of the human mind to know more
00:08:39 Or the quest of the human spirit to express itself in new ways
00:08:45 Progress
00:08:58 We cannot stop progress
00:09:00 But society must have the wisdom to recognize that our scientific knowledge and technological capabilities have their limitations
00:09:08 Because something is done well does not mean that it cannot be done better
00:09:14 The challenge facing us is not to stop progress but to shape it
00:09:19 We must change existing technologies and create new ones that will allow us to manufacture products that do not harm the environment
00:09:28 Catalysis provides the key to accomplishing this, not in the future but now
00:09:33 Catalytic technology is ready to meet this challenge
00:09:44 Progress
00:09:56 Smog
00:09:57 That unfortunate emblem of modern urban life
00:10:00 A major component of smog is ozone
00:10:03 Unlike the ozone in the upper atmosphere that shields the earth from the ultraviolet rays of the sun
00:10:09 Ground level ozone is a health hazard and results when gaseous pollutants such as nitrogen oxide and hydrocarbons react in the presence of sunlight
00:10:19 Perhaps the most widely recognized contribution to the modern world made by catalytic science is to be found in the reduction of exhaust emissions from our cars
00:10:30 Only 20 years ago the terms catalytic converter and smog check were new to most of us
00:10:37 Nowadays both terms are as much a part of our automotive vocabulary as seat belts, airbags and anti-lock brakes
00:10:50 This chemist is among the many who continue research into catalytic converters
00:10:55 This is a catalytic converter that you might see under the floorboard of any one of today's cars
00:11:00 This is what you do see but what you don't see is what's in the inside
00:11:06 What's on the inside looks something like this
00:11:10 This is a catalyst, an extruded ceramic brick that is used to destroy emissions from automobiles in your cars today
00:11:18 Catalyst starts its life looking something like this
00:11:22 Then it's dipped in a solution containing catalytic materials
00:11:27 Those catalytic materials bond to the surface and provide the activity that is needed for the catalyst to destroy emissions
00:11:34 This brick is then placed within the body of this metal casing which is put underneath your car where it does its work
00:11:43 What happens inside this casing is that the polluting gases flow into the catalyst
00:11:51 These polluting gases are basically carbon monoxide, hydrocarbons and nitrogen oxides
00:11:57 Within the catalyst they're converted into carbon dioxide, water and nitrogen, all of which are non-toxic to the environment
00:12:06 Cars produced today are 20 to 30 times cleaner than cars produced in 1970, the year the Clean Air Act was signed into law
00:12:16 Within four years of its signing, American Catalytic Science and Engineering designed, produced and made ready for installation the first generation of catalytic converters
00:12:28 But with the tremendous increase in the number of cars on the road and the length of many commutes, the auto emission problem is still with us
00:12:37 The technology of the catalytic converter is continuously being improved
00:12:42 One promising step in this direction is the electrically heated catalytic converter
00:12:48 The majority of pollutants in today's cars are emitted during the first couple of minutes after an engine is started
00:12:54 The reason why is the catalyst must reach a certain temperature for a reaction to occur
00:13:00 The ceramic catalysts that we use today just don't heat up very fast
00:13:05 So we need to come up with new solutions to take care of these initial emissions
00:13:09 One of the new solutions is an add-on catalyst made of a metal type of product
00:13:14 Why metal?
00:13:16 Metal because metal can be electrically heated, can be connected to a battery so that we can warm up this catalyst very, very quickly to take care of these cold start emissions
00:13:26 This particular catalyst can warm up to reaction temperatures within the first 8 or 10 seconds after a car engine is started
00:13:34 The electrically heated catalytic converter is one example of ways in which automobile emissions can be reduced
00:13:42 But auto emissions pose too big a challenge to be approached on just one front
00:13:48 Sound of engine starting
00:14:01 Catalysts have long been used to make gasoline and other fuels for the transportation industry
00:14:06 But they have played critical roles in recent history as well
00:14:11 Air raid, London, 1940
00:14:17 The Battle of Britain
00:14:19 The Luftwaffe is exacting a tremendous toll on the RAF
00:14:23 The German aircraft simply seems superior to the British
00:14:27 Hitler's planned invasion of England is imminent
00:14:31 American scientists and engineers work around the clock to develop better fuel for the British aircraft
00:14:38 They believe higher octane fuel is the answer
00:14:41 The way to achieve this higher octane?
00:14:44 Catalysis
00:14:46 The new fuel provides the British aircraft with bursts of acceleration 50% greater than before
00:14:52 This improved performance provided the margin of victory
00:14:56 A victory made possible by catalysis
00:15:00 In a real sense, today's battles are no less important for the future of society
00:15:05 Or more challenging to American technology
00:15:08 For instance, the gasoline that we use in our cars
00:15:12 Can it be made in such a way that it contains fewer potential pollutants?
00:15:16 It must, and can
00:15:19 Both the petroleum and auto industries are constantly testing fuels
00:15:24 Both for performance and for the levels of emissions
00:15:28 Emissions from automobiles occur in two basic ways
00:15:31 Through the tailpipe while driving, and by evaporation
00:15:35 For example, when we gas up at the fuel pump
00:15:39 Catalysts attack both sources of emission by altering the composition of the gasoline mixture
00:15:45 These alterations to the composition have resulted in new blends of gasoline
00:15:50 So-called designer or reformulated gasolines
00:15:53 That will burn more cleanly and evaporate less easily
00:15:59 To put this question of auto emissions into perspective
00:16:02 Let's take a look at a specific example
00:16:05 Scientists and engineers in Baton Rouge, Louisiana
00:16:09 Have set up stations in the area to collect air samples
00:16:12 That provide data about the level of gasoline emissions in the air
00:16:17 Shepard Burton is an atmospheric scientist
00:16:20 Who's developed computer simulated models of emissions in the lower atmosphere
00:16:24 In these time-lapse computer animations
00:16:28 We can see the ozone concentrations
00:16:31 We can see, for example, the changes in ozone levels
00:16:34 That would result from modifications to reformulated gasoline
00:16:37 Or modifications to chemical plant and refinery processes
00:16:40 That go in to make chemical products or gasoline
00:16:43 We can repeat these kinds of simulations for numerous cities throughout the United States
00:16:49 It's currently being used in about 30 cities in the United States
00:16:54 With the model we can address a number of what-if questions
00:16:59 Questions such as how the ozone levels in an urban area would change
00:17:04 In response to improvements in the formulation of gasoline
00:17:07 Or in reducing emissions
00:17:10 And in this way we can also examine
00:17:13 Not only what the magnitude of the emissions changes would be
00:17:17 But also what the expected improvement in air quality would be
00:17:22 This reformulation effort is one of the most important challenges ever to face American industry
00:17:28 The work being carried out in Baton Rouge
00:17:31 Is part of an industry-wide undertaking to meet federal mandates
00:17:35 And to develop fuels that will produce only a fraction of the emissions put out by those currently in use
00:17:42 Once again, catalysis provides the key to success
00:17:50 What specific kinds of catalysts are playing such an important role in the reformulation of gasoline?
00:17:57 Zeolites are different from other crystalline materials
00:18:00 In that they have a pore system which allows internal access to the interior of the crystal
00:18:06 The pore system provides a high surface area on which chemical reactions can take place
00:18:12 And in this respect the zeolite itself becomes a catalyst for chemical reactions
00:18:17 The regular size and shape of the pore system
00:18:20 Permits certain size molecules to enter the pore
00:18:23 And other molecules which are too large or the wrong shape
00:18:26 Such as this large organic molecule will not be allowed inside the pore system
00:18:30 And cannot undergo a chemical reaction
00:18:32 A molecule of just the right size and shape
00:18:35 Such as this long, waxy hydrocarbon
00:18:39 Can enter the pore system, undergo a chemical reaction
00:18:42 And be converted into gasoline, clean fuels and other products
00:18:51 Energy
00:18:53 Power
00:18:54 Do we want to live without them?
00:18:57 Could we live without them?
00:19:04 Stack emissions
00:19:06 Another challenge for science and engineering
00:19:09 In spite of our efforts thus far
00:19:11 Power plants are a major source of air pollution
00:19:14 It is estimated for example
00:19:16 That about half of all nitrogen oxide emissions come from coal and other fossil fuel burning power plants
00:19:23 Nitrogen oxide and sulfur dioxide emitted from these plants
00:19:27 Contributes to the creation of acid rain
00:19:32 Again, we look to catalysis to help us solve these problems
00:19:36 One technique developed selectively reduces specific contaminants
00:19:41 By converting them to harmless molecules
00:19:43 In this process, ammonia is fed into the stream of the harmful nitrogen oxides
00:19:50 When this mixture is passed through a reactor filled with a catalyst
00:19:53 The nitrogen oxide reacts with ammonia
00:19:56 In such a way that it is converted to harmless nitrogen and water
00:20:01 To perform this process over an extended time
00:20:04 Catalysts have been developed that are durable and resistant to contamination by the polluting gases
00:20:12 One such catalyst consists of an active ingredient coated on heavy metal foil
00:20:17 This catalyst is used in natural gas fired power plants
00:20:20 Where potentially polluting emissions of nitrogen oxide are prevented from escaping into the atmosphere
00:20:27 In harsher environments, other kinds of catalysts are used
00:20:33 The pollutant containing gases of coal fired power plants
00:20:37 Contain dust and grit that can damage the catalyst we just saw
00:20:43 A new application requires a different catalyst
00:20:46 These are often made of ceramic materials with relatively large pores
00:20:50 Into which the ash laden gases can enter and undergo the appropriate reaction
00:20:56 Each year, over one million tons of nitrogen oxide are being rendered harmless by these special catalysts
00:21:05 With the installation of advanced catalytic systems such as these
00:21:09 Power plant emissions can be reduced to very low levels
00:21:13 This victory will not be as dramatic as the Battle of Britain
00:21:16 But its ultimate impact on the quality of our lives will be just as great
00:21:27 While quality of life has always been important to Americans
00:21:31 The years following World War II marked the beginnings of rapid and remarkable changes in the way we live
00:21:38 By the early 1950s, for instance, the Iceman was quickly becoming a figure of the past
00:21:45 Through catalysis, new compounds were developed that forced the old icebox to yield to a new appliance
00:21:51 That not only kept food cool and fresh, but also itself made ice
00:21:56 Before long, the home refrigerator put undreamed of possibilities into the hands of everyone
00:22:02 These new refrigerants also brought about basic changes in our expectations about our work environments
00:22:08 On a larger scale, refrigeration was used to air condition entire buildings
00:22:13 Bringing to many workplaces a level of comfort the modern world takes for granted
00:22:19 And it wasn't long before people began to want this same kind of comfort in their homes and automobiles
00:22:26 In the early days of computers, the large amounts of heat generated by the machines had to be dissipated and the space kept cool
00:22:34 Otherwise the computers would not run
00:22:37 This cooling was made possible through refrigeration
00:22:44 Advances in catalysis, the development of new compounds, the birth of modern refrigeration
00:22:52 A chain of events that has revolutionized the environments in which we live and work
00:22:59 As well as our ability to store safely food and other precious commodities
00:23:08 Progress, however, sometimes comes at a price
00:23:12 Scientists have recently discovered that we are faced with one of the most serious problems of our age
00:23:18 The depletion of the stratospheric ozone layer by CFCs, chlorinated fluorocarbons
00:23:24 Molecules that form the basis of the materials used for refrigeration and air conditioning
00:23:30 Chlorine atoms from the CFCs escape into the stratosphere
00:23:34 A zone that extends from about 12 to 30 miles above the surface of the earth
00:23:40 There, the ozone gases that keep the ultraviolet rays emitted by the sun at safe levels react with these chlorine atoms
00:23:48 In this reaction, the ozone gases are the losers and their numbers are depleted
00:23:56 With the help of catalysis, producers of refrigerants are trying to find substitutes for CFCs
00:24:02 But the job is not an easy one
00:24:04 Dr. Leo Manzer is a chemist for a large corporation who has been managing a major research effort to find alternatives to CFCs
00:24:13 The hydrofluorocarbons and hydrochlorofluorocarbons are complicated molecules
00:24:17 You can't simply take A plus B and make C out of these reactions
00:24:22 They have to take place on a catalytic surface
00:24:25 And it's the catalyst that makes this chemistry go in very, very high yield
00:24:30 Without catalyst, there is no reaction, there would be no CFCs or no alternatives
00:24:34 Catalyst is the answer
00:24:36 Currently, there's $200 billion worth of equipment in supermarket freezers, in homes, in office buildings, in the hot parts of the country
00:24:45 Many places you can't even open the windows
00:24:47 Those buildings are put in around the air conditioning systems
00:24:51 We need to find ways to convert those existing pieces of equipment over to these new alternatives
00:24:58 That takes quantities of materials, the plants have to be built
00:25:02 So developmental quantities can be provided to the users, the people that make the equipment
00:25:09 The clear answer is that we need to get chlorine out of the atmosphere so that it can't decompose the ozone layer
00:25:16 And we continue to search for the best environmentally safe materials that we can find
00:25:28 While this particular kind of plastic will eventually degrade without depleting the ozone layer
00:25:33 No one wants to see it end up here where it does not belong
00:25:37 Our efforts to protect the environment should begin here
00:25:41 Keeping materials in places they belong and out of places where they do not belong
00:25:48 But inevitably, some of the byproducts of things we use in our daily lives do end up in waste streams
00:25:54 We have to deal with these byproducts and dispose of them in a way that is environmentally sound
00:26:01 Catalysis, as it operates in the heart of nature itself, provides us with ideas about how to do this
00:26:14 Without our realizing it, catalysis occurs in nature before our very eyes
00:26:20 This water, for example, is purified in part by microbes
00:26:24 Which ingest carbon matter and organic particulates as they float downstream
00:26:29 In fact, these microbes are biological catalysts at work
00:26:35 Professor Ralph Portier of Louisiana State University has been studying ways to apply the principles of biological catalysis
00:26:43 To the treatment of municipal and industrial wastes
00:26:46 He has found a way to combine, or permanently fix, a microbe to a supporting material
00:26:52 In this case, a catalyst support bead
00:26:56 Within this tiny bead is a living catalyst made up, if you will, of a community of microbes
00:27:02 These fixed microbial communities can be used for a multitude of environmental cleanup jobs
00:27:09 The beauty of an enzyme-based treatment system is that an enzyme can recognize the concentration of a toxicant in a wastewater at the part per billion level
00:27:20 So these enzymes, think of them as chemical keys unlocking a compound
00:27:26 Can break apart the organic in question in such a form that the microbes can then recognize it and use it as food
00:27:35 Magnified 10,000 times, this microbial community can handle extreme concentrations of toxicants
00:27:42 This is the beauty of a biocatalyst in that it can handle high concentrations in a very small space
00:27:53 Modular reactor beds like this one, developed by Professor Portier
00:27:57 Allow many of our older industrial plants to be retrofitted so that they meet new environmental regulations for water and air purity
00:28:06 Because of their relative portability, these beds are also being used for on-site treatment of contaminated groundwater and other localized pollution problems
00:28:16 Groundwater contamination is a major problem facing industry throughout the United States
00:28:21 Here we're using a biocatalyst, a controlled microbial community on a surface, to treat groundwater as it's pumped from underneath an existing landfill at this chemical plant
00:28:32 The idea is to pump the water through the microbial community, allow the microbes to degrade the toxic chemicals in the groundwater, and allow that water to be discharged safely
00:28:43 Transporting oil by sea is a part of modern life
00:28:52 There are risks involved, and even though precautions are taken, accidents do happen
00:28:59 Now, new biological catalysts help us deal with such accidents
00:29:05 In the case of the spill at Prince William Sound, bioremediation was used to clean up 72 miles of coastline
00:29:12 Microbes indigenous to the area were combined with a fertilizer to provide nutrients for the microbes
00:29:18 The microbes then produced the enzymes that acted as the catalyst necessary to break down the oil
00:29:26 With the fertilizer providing a steady source of nourishment for the microbes, more enzymes were produced, thus speeding up the breakdown of the oil into biomass
00:29:36 This biomass then re-entered the food chain
00:29:41 A major lesson learned from this accident is that if an oil spill should occur, immediate steps must be taken to prevent it from reaching the coastline
00:29:52 With this as a goal, a new bioremediation technique is being developed that shows great promise for cleaning up oil spills at sea before they can reach land
00:30:02 As seen in this simulation, this technique makes use of a biocatalyst and an inert catalyst material spread over an oil slick
00:30:12 Under test conditions, it has been demonstrated that spilled crude oil can be herded or clumped into smaller, more manageable segments for recovery by traditional booms
00:30:23 All indications point to biocatalysts becoming an essential tool in our efforts to keep the environment clean
00:30:31 Catalytic science and technology
00:30:34 We looked to it in the past for help, and it gave it
00:30:38 We look to it for the future, and it will give it again by allowing us to generate environmentally friendly technologies
00:30:49 By helping us to control emissions, by remediating the effects of pollution, and by actually preventing pollution in the very process of manufacturing
00:31:03 Catalysis will allow us to make the products we need while keeping our air clean, our water pure, and our land safe for ourselves and for future generations
00:31:33 www.globalonenessproject.org
00:32:03 www.globalonenessproject.org