Seven Important Chemical Separations
May 19, 2016
Good chemists supposedly make good cooks, since cooking and chemistry have many things in common. You need to select the correct ingredients, measure them carefully, choose the right utensils and containment vessels, and process your mixtures at the proper temperature for the proper time. For an analytical touch, you even sample the product at stages and adjust things accordingly.
This cooking-chemistry analogy has become more concrete of late with the emergence of molecular gastronomy. Molecular gastronomy, as defined in an early article on the topic in a publication of the Royal Society of Chemistry, is "...the application of scientific principles to the understanding and improvement of small-scale food preparation."
Physicists have been more associated with molecular gastronomy than chemists. The method was first described in 1799 by physicist, Benjamin Thompson, also known as Count Rumford. It was named molecular gastronomy in 1988 by Nicholas Kurti, a University of Oxford physicist, and Hervé This, a French physical chemist.
In 2011, physicist, Nathan Myhrvold, along with Chris Young and Maxime Bilet, published the five volume cookbook, Modernist Cuisine: The Art and Science of Cooking about scientific cooking. Myhrvold's interest in the topic was inspired by his failure to find any good information about sous-vide cooking. Myhrvold is known, also, as a former chief technology officer of Microsoft and the co-founder of Intellectual Ventures.
Reactions are the heart of chemistry. If I look beyond the oxidation reactions that sustain life, I can name the Maillard reaction as my favorite reaction. This chemical reaction between amino acids and sugars is a part of cooking chemistry, since it's the reaction that imparts so much flavor when certain foods are browned in cooking. This reaction flavors such things as breads, biscuits and French fries.
This reaction was first described in 1912 by the French chemist, Louis-Camille Maillard. The reaction happens rapidly at about 140-165 °C (284-329 °F), and it produces hundreds of different flavor compounds. An alkaline environment, such as a coating of lye on pretzels, accelerates the reaction, giving a deep brown color. Quality control is important, since acrylamide, a possible carcinogen, can be produced at high temperatures.
While food might be close to my heart (as in "the way to a man's heart is through his stomach"), there is more to chemistry than just chemical reactions. Chemical separations are methods of converting a mixture into products, called fractions, at least one of which is enriched in a chemical of interest. David S. Sholl and Ryan P. Lively, both professors in the School of Chemical and Biomolecular Engineering of the Georgia Institute of Technology (Atlanta, Georgia), have just published their opinion on the seven such chemical separations that would qualify as world changing.[4-5]
As Ryan Lively, study co-author and an assistant professor in Georgia Tech's School of Chemical & Biomolecular Engineering, explains,
"Chemical separations account for about half of all U.S. industrial energy use... Developing alternatives that don't use heat could dramatically improve the efficiency of 80 percent of the separation processes that we now use."
Sholl and Lively chose the following as the seven most important chemical separations: Hydrocarbons from petroleum, uranium from sea water, alkenes from alkanes, greenhouse gases from dilute emissions, rare earth metals from ores, benzene derivatives from each other, and trace contaminants from water. They write that the present separation methods are responsible for 10-15% of the world's energy consumption.
Hydrocarbons from petroleum
Uranium from sea water
Nuclear power is a carbon-free energy source, but you need uranium fuel for this option. As it turns out, there are more than four billion tons of uranium dissolved in seawater. Chemical separation of uranium from seawater is complicated by the chemically-similar elements vanadium and cobalt. There have been small scale tests of improved processes, but much work is still needed to be done.
Alkenes from alkanes
Alkenes such as ethylene and propene are used to produce certain polymers. The total annual production of alkenes is greater than 200 million tons, and an energy-intensive step is the separation of alkenes from their single-bonded counterparts, such as ethylene from ethane. Membranes are a potential energy-saving separation technology, but an industrial-scale plant would require a million square meters of membrane.
Greenhouse gases from dilute emissions
Presently, scrubbing of carbon dioxide and hydrocarbon stack emissions is done by reaction with liquid amines, with an additional heating step required to recover the amine to its initial state. A better method is needed.
Rare earth metals from ores
The rare earth elements are used in the powerful magnets that enable motors and actuators for many applications, and also for some catalysts. They tend to occur together in nature and are chemically similar, so their separation from ores is difficult.
Benzene derivatives from each other
Benzene and its derivatives are used in the production of many materials, solvents and fuel additives. Distillation columns, similar to the petroleum example above, are now used to separated these. About 50 gigawatts of energy are used for this purpose annually. Membrane and sorbents could be developed for a more energy-efficient process.
Trace contaminants from water
As the Flint, Michigan, water crisis reminds us, we sometimes must purify our water before drinking. In many parts of the world, water desalination is an important process, and it's both energy and capital intensive. Some membrane processes are now used, but research is needed to solve problems such as fouling, and to make desalination more energy efficient.
Says co-author David Sholl, chair of Georgia Tech's School of Chemical & Biomolecular Engineering,
"We wanted to highlight how much of the world's energy is used for chemical separations and point to some areas where large advances could potentially be made by expanding research in these areas... These processes are largely invisible to most people, but there are large potential rewards - to both energy and the environment - for developing improved separation processes in these areas."
- Cooking with chemistry, Chemistry in Britain (Chemistry World), no. 10 Royal Society of Chemistry, October 2003.
- Nathan Myhrvold, Chris Young, and Maxime Bilet, "Modernist Cuisine: The Art and Science of Cooking," The Cooking Lab, March 7, 2011, ISBN 978-0982761007, 2438 pp. (Modernist Cuisine Web Site).
- L-C Maillard, "Action des acides amines sur les sucres: Formation des melanoidines par voie methodique," Comptes Rendus, vol. 154 (1912), pp. 66-68.
- David S. Sholl and Ryan P. Lively, "Seven chemical separations to change the world," Nature, vol. 532, no. 7600 (April 28, 2016), pp. 435-437. This is an open access article with a PDF file available here.
- John Toon, "Researchers List 'Seven Chemical Separations to Change the World'," Georgia Institute of Technology Press Release, April 27, 2016.
Permanent Link to this article
Linked Keywords: Chemist; cooking; cook; chemistry; ingredient; measurement; measure; food preparation utensil; bowl; vessel; temperature; analytical chemistry; analogy; molecular gastronomy; academic publishing; publication; Royal Society of Chemistry; science; scientific; food preparation; physicist; Benjamin Thompson; Nicholas Kurti; University of Oxford; Hervé This; France; French; physical chemistry; physical chemist; portrait; Count Rumford; Moritz Kellerhoven (1758-1830); experiment; mechanical equivalent of heat; friction; cannon; boring; boring tool; boiling; boil; water; Wikimedia Commons; Nathan Myhrvold; Modernist Cuisine: The Art and Science of Cooking; sous-vide; chief technology officer; Microsoft; Intellectual Ventures; chemical reaction; oxidation reaction; respiration; sustain life; Maillard reaction; amino acid; sugar; flavor; browning; brown; bread; biscuit; French fries; Evan-Amos; Louis-Camille Maillard; Celsius; Fahrenheit; alkalinity; alkaline environment; lye; pretzel; quality control; acrylamide; carcinogen; heart; the way to a man's heart is through his stomach; separation process; chemical separation; product; fraction; David S. Sholl; Ryan P. Lively; professor; School of Chemical and Biomolecular Engineering; Georgia Institute of Technology (Atlanta, Georgia); industry; industrial; energy; heat; efficiency; hydrocarbon; petroleum; uranium; sea water; alkene; alkane; greenhouse gas; rare earth element; metal; ore; benzene; contamination; contaminant; world energy consumption; distillation; barrel; crude oil; gigawatt; vapor; condensation; condense; nuclear power; low-carbon power; carbon-free energy source; ton; vanadium; cobalt; ethylene; propene; polymer; single-bond; ethane; membrane; square meter; carbon dioxide; flue-gas stack; stack emission; amine; rare-earth magnet; electric motor; actuator; catalysis; catalyst; nature; material; solvent; fuel additive; fractionating column; distillation column; sorbent; Flint, Michigan, water crisis; purified water; capital cost; fouling; chairman; research; environment.
Latest Books by Dev Gualtieri
Thanks to Cory Doctorow of BoingBoing for his favorable review of Secret Codes!
Blog Article Directory on a Single Page
- The Wisdom of Composite Crowds - April 27, 2017
- J. Robert Oppenheimer and Black Holes - April 24, 2017
- Modeling Leaf Mass - April 20, 2017
- Easter, Chicks and Eggs - April 13, 2017
- You, Robot - April 10, 2017
- Collisions - April 6, 2017
- Eugene Garfield (1925-2017) - April 3, 2017
- Old Fossils - March 30, 2017
- Levitation - March 27, 2017
- Soybean Graphene - March 23, 2017
- Income Inequality and Geometrical Frustration - March 20, 2017
- Wireless Power - March 16, 2017
- Trilobite Sex - March 13, 2017
- Freezing, Outside-In - March 9, 2017
- Ammonia Synthesis - March 6, 2017
- High Altitude Radiation - March 2, 2017
- C.N. Yang - February 27, 2017
- VOC Detection with Nanocrystals - February 23, 2017
- Molecular Fountains - February 20, 2017
- Jet Lag - February 16, 2017
- Highly Flexible Conductors - February 13, 2017
- Graphene Friction - February 9, 2017
- Dynamic Range - February 6, 2017
- Robert Boyle's To-Do List for Science - February 2, 2017
- Nanowire Ink - January 30, 2017
- Random Triangles - January 26, 2017
- Torricelli's law - January 23, 2017
- Magnetic Memory - January 19, 2017
- Graphene Putty - January 16, 2017
- Seahorse Genome - January 12, 2017
- Infinite c - January 9, 2017
- 150 Years of Transatlantic Telegraphy - January 5, 2017
- Cold Work on the Nanoscale - January 2, 2017
- Holidays 2016 - December 22, 2016
- Ballistics - December 19, 2016
- Salted Frogs - December 15, 2016
- Negative Thermal Expansion - December 12, 2016
- Verbal Cues and Stereotypes - December 8, 2016
- Capacitance Sensing - December 5, 2016
- Gallium Nitride Tribology - December 1, 2016
- Lunar Origin - November 27, 2016
- Pumpkin Propagation - November 24, 2016
- Math Anxiety - November 21, 2016
- Borophene - November 17, 2016
- Forced Innovation - November 14, 2016
- Combating Glare - November 10, 2016
- Solar Tilt and Planet Nine - November 7, 2016
- The Proton Size Problem - November 3, 2016
Deep Archive 2006-2008