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Industrial Alchemy, Part 1: The New Philosopher's Stone

Written by Iver P. Cooper

In alchemical thought, the Philosopher's Stone is a fantastical artifact which is capable of transmuting base metals into gold. The new Philosopher's Stone is not an artifact, but knowledge—the teachings of twentieth century chemistry as transmitted by the up-timers and their books—and while it can't change one element into another, it can and will change how the down-timers think about the world they live in.

About three thousand up-timers were thrown into the seventeenth century by the Ring of Fire. Of those, perhaps a score have significant college training in chemistry, and of course there are many more who have recently taken a high school chemistry course.

That said, there are thousands of chemicals which we would like to make. The knowledgeable up-timers can't do it all themselves. It is essential that they train new chemists from the vast population of down-timers.

Some of those trainees will be youngsters, and others will be experienced alchemists. The down-time alchemists have a lot of practical knowledge which is still of value. They are familiar with the gross chemical and physical properties of many substances, although the purity of the substances in question is debatable. They have carried out some of the basic manipulations of the chemical laboratory, such as melting, dissolving, crystallizing, filtering and distilling chemicals.

The down-time alchemists are going to be getting a crash course in modern chemistry. Some of the alchemists will become wholesale converts to modern chemistry. Others will treat it more as the Aristotelians did the Copernican cosmology; as a convenient fiction.

Modern science, including chemistry, will also be seeping into the general curriculum. Perhaps some of the students will aspire to become chemists. (The man who is sometimes called the Father of Chemistry—Robert Boyle—was four years old when Grantville was hurled into 1631 Thuringia.)

 

Chemical Resources in Grantville

 

In Lord Kalvan of Otherwhen, Corporal Calvin Morrison becomes the eponymous Lord Kalvan because he happens to know the recipe for gunpowder, a combustible mixture of charcoal, saltpeter and sulfur. This is proof that every time traveler should know some chemistry!

The time travelers of the 1632verse know quite a bit of chemistry, actually. There are six up-timers with a bachelor's degree in chemistry: Allan Dailey (b. 1964), Greg Ferrara (1970), Thomas “Tom Stoner” Stone (1950s)(also has M.A. Pharmacy and doctoral course work), Alexandra (Lilburn) Selluci (1943), Walter Miller (1927-1636), and Dominic Genucci (1977 graduate course work). It is a safe bet that they have kept their chemistry textbooks from college. Each probably also has an edition of the "CRC" and perhaps additional chemistry books.

Christie (Kemp) Penzey has a degree in geology. She teaches chemistry, and is the "technical adviser" for the Kubiak experiments on recreating baking powder (Offord, "The Doctor Gribbleflotz Chronicles, Part 1:Calling Dr. Phil", Grantville Gazette 10).

Nine more up-timers have degrees in pharmacy, and Jerry Trainer's degree is in chemical engineering.

Several more up-timers do not have a college degree, but are getting advanced training in chemistry: Amy Kubiak, Tonya Daoud, Tyler Beckworth, Sam Reed, Mark Dalton Higgins, Lewis Philip Bartolli, Mary Lou (Cantrell) Snell and Kerry Burdette Douglas are laboratory technicians.

The high school in Grantville is modeled on North Marion High School (Farmington, WV). It offers a surprisingly wide range of science courses. Grades 9 and 10 receive an integrated science course ("CATS") that is apparently a continuation of a program begun in Grade 7. Eleventh and twelfth graders can take Advanced Environmental Earth Science, Advanced Chemistry, Advanced Placement Chemistry, Advanced Placement Earth Science, Earth and Sky (a college level class), Microbiology and even Forensics ("topics include ballistics, fingerprinting, and the analysis of inorganic and organic compounds"). Lewis Bartolli's knowledge of forensic science (see my stories "Under the Tuscan Son," Grantville Gazette 9 and "Arsenic and Old Italians," Grantville Gazette 22) is based on more than just reading detective stories!

What we need most is information on descriptive inorganic chemistry, and this subject tends to get short shrift in modern general chemistry and inorganic chemistry courses. Fairmont State presently uses the fourth edition of Brady, Chemistry: The Study of Matter, and I think there is a good chance of finding the third edition (1988) in Grantville. As for more advanced texts, I am sure that there is at least a copy of Cotton and Wilkinson, Advanced Inorganic Chemistry (CW); I used the third edition at MIT. (A JCE review of the sixth edition called it "the most popular inorganic chemistry textbook ever published"). I was pleasantly surprised to discover that the high school has the McGraw-Hill Encyclopedia of Science & Technology (4th ed., 1977; 15 vols.).

As for equipment, as I said in my aluminum article (Gazette 8), the power plant has a "Metallurgist XR," which is a portable X-ray fluorescence spectrophotometer specifically designed for alloy analysis. (Boyes) And, even more surprisingly, the high school has a $300,000 atomic absorption spectrophotometer given to them in October 1997 by LaFarge Corp.

 

Prominent Alchemists

 

I referred to "industrial alchemy" rather "industrial chemistry" as a gentle reminder that for every up-time chemist, there are hundreds of down-time alchemists.

We can expect visits (and perhaps citizenship applications) from the prominent alchemists of early seventeenth century Europe.

Michael Sendivogius (1566-1636) did pioneering research on the composition of air, discovering that it was a mixture of substances, including one (now called oxygen) that supports life. His patrons are the Polish Vasas. Of course, they are more interested in his claim to be able to transmute mercury into gold.

Cornelius Drebbel (1572-1633) (died in OTL shortly after the RoF, but this could be butterflied) is perhaps best known for his submarine, but he invented a thermostat and the dye known as "color Kufflerianus."

Arthur Dee (1579-1651)(the physician to Michael I of Russia) wrote Fasciculus chemicus (1630), a compendium of alchemical bon mots.

Jan Baptist van Helmont (1580-1644) was an early contributor to the development of the law of conservation of mass. He appears as a character in Mackey, "Ounces of Prevention" (Grantville Gazette 5).

Johann Rudolf Glauber (1604-1670) was the first to produce hydrochloric acid and sodium sulfate. In OTL 1648 he developed a major method of manufacturing sulfuric acid. In NTL, he developed the potassium chlorate-based percussion caps for the French "Cardinal" rifles (1634: The Baltic War, Chapter 27).

Several other notable alchemists were born before the Ring of Fire, but were young enough when it occurred that they may be "butterflied" into a different line of work: Elias Ashmole (1617-1684), Robert Boyle (1627-1691)(the "Father of Modern Chemistry"), George Starkey (1628-1665) and Hennig Brand (1630-1670).

 

Commodity and Specialty Chemicals

 

A commodity chemical is one that is produced in great quantity, whereas a specialty chemical has a more limited market.

Judging from Posthumus' studies of commodity exchange prices in the Netherlands, the inorganic chemical commodities in 1630s Europe included the elements iron, tin, lead, gold, silver, copper, mercury and sulfur; the alloys steel, brass, and spelter (a zinc); the compounds common salt (sodium chloride), copperas (ferrous sulfate), potash (potassium carbonate),white potash (potassium chloride), soda (sodium carbonate), saltpeter (potassium nitrate), alum (potassium aluminum sulfate), and borax (sodium borate); and gunpowder (a mixture of sulfur, saltpeter and charcoal).

 

Changes in Demand

 

The arrival of Grantville will change the chemical marketplace. Some chemicals will be demanded because of their value as end-products, others, for use as starting materials or reagents.

The principal chemicals in the first decade after the RoF will not necessarily be those that are prominent nowadays. In particular, those inorganic chemicals whose principal utility is in making organic chemicals may be disdained until the necessary organic raw materials are isolated in reasonable quantities.

That said, it is worth using late-twentieth century compilations as a starting point. The top inorganic chemicals in the late-twentieth century are listed in Table 1-1. Most, if not all, of those compounds are going to be important in the first decade after RoF, too. (I am a bit uncertain about titanium dioxide, since titanium ores have never been mined by the down-timers.)

Inorganic Chemicals in Canon

 

The following inorganic chemicals are known to be in canon. The years given are those of their "canon appearance"; they may in fact have been made earlier (unless canon actually says "this is a first"). The chemicals marked with * were actually known to down-timers before RoF. Further details appear in later parts of this article.

1631-32: sulfuric acid*, nitric acid*, sodium bicarbonate,

1633: zinc sulfide* (sphalerite), natural cryolite (sodium aluminum fluoride), mercury fulminate, ammonia*, calcium hypochlorite, ammonium nitrate, [and by implication, chlorine, chlorosulfonic acid, hydrochloric acid*, calcium hydroxide]

1634: sodium hydroxide*, chromium ore (chromite), potassium chlorate, boric acid, borax*, hydrogen, graphite*

1635: calcium carbide

1636: synthetic cryolite, hydrogen fluoride

 

Infrastructure Problems

 

A twentieth-century chemist can buy, off the shelf, pure chemicals, borosilicate laboratory glassware, and accurate measuring equipment (thermometers, pH meters, analytical balances, etc.) The life of the "industrial alchemist" is going to be more difficult.

Mackey, "Ounces of Prevention" (Grantville Gazette 5) illustrates this by reference to the ring nitration step in chloramphenicol synthesis, which must be performed at near-freezing temperatures. Von Helmont complains he needs very pure sulfuric and nitric acids, and that the Essen Instrument Company has a six month backlog of orders for precision mercury thermometers.

In reference to fulminate production, Christie Penzey tells Mike, "we can't just call up our friendly chemicals supplier and ask for a few hundred gallons of pure nitric acid. We have to triple distill everything, even the water we use." Offord and Boatright, "The Dr. Gribbleflotz Chronicles, Part 2: Dr. Phil's Amazing Essence Of Fire Tablets" (Grantville Gazette 7)

The reactions which I expect will be the most difficult to duplicate early in the new time line are those which require special conditions (high or low pressure, unusual catalysts, or even high or low temperatures) or which are very finicky in their requirements for pure solvents and reagents. Unfortunately, modern industrial chemistry, especially organic chemistry, places great reliance on exotic catalysts.

 

Qualitative Analysis

 

Qualitative analysis answers the question, "Is it present?" There is a reasonable chance that at least one up-time chemist took a qualitative analysis course and has the textbook for it. If so, then it will be possible to determine the presence or absence of many common ions (electrically charged chemicals). Even without it, there is quite a bit of useful information in the encyclopedias, general chemistry textbooks, and the CRC.

Dry Analysis. In the flame test, the sample solution is dried on a wooden splint, or a platinum or nichrome wire, and waved through an "invisible" flame. The heat excites electrons in metal ions. The electrons eventually release energy, and for some ions, this happens in steps which correspond to one of the colors of visible light. For example, sodium is blue; boron is green, and calcium is red. Note that different ions can produce the same flame color, so this test is far from definitive.

In the borax bead test, a bead of borax, held on a platinum wire, is dipped in the sample, and then heated in the lower, reduction zone of the flame, and allowed to cool. You then heat it in the upper, oxidation zone, and let it cool. You observe its colors, hot and cold, and oxidized and reduced. The combination is indicative of which metal is present.

The sample may also be placed on a piece of charcoal, and a blowpipe used to control the flame.

Wet Analysis. The principal qualitative analysis methods exploit differences in reactivity and solubility. The method described in EB11/Chemistry) divides the metals into six groups; further reactions are needed to identify a particular ion within a group.

See also the EB11 entries for the tests specific to individual elements. Maria Vorst alludes to the cobalt nitrate test for aluminum in Cooper, "Stretching Out, Part 3: Maria's Mission" (Grantville Gazette 14), and Lewis Bartolli to the turmeric test for boric acid in Cooper, "Under the Tuscan Son" (Grantville Gazette 9).

 

Quantitative Analysis

 

Quantitative analysis answers the question "how much?" As might be expected, these techniques are more exacting than those of qualitative analysis.

Gravimetric analysis involves converting all of the chemical of interest (and only that chemical) to a precipitate and then weighing it.

Volumetric analysis requires adding, drop by drop ("titration"), a known volume of a standard solution of an analytical reagent that reacts with (and only with), the chemical of interest, until a "signal" evidences that all of the target chemical has reacted. The "signal" can be a color change achieved by an "indicator" chemical, or a change in the electrical characteristics of the solution.

The concentration of a compound in pure solution can be determined by measuring the degree to which it rotates the plane of polarization of linearly polarized light of a particular wavelength passing through the solution. You need to know the specific rotation of the compound (how much it rotates the plane over a unit path length) and the path length through the solution.

Spectroscopic analysis involves causing the chemical to emit or absorb light of various wavelengths (visible, infrared or ultraviolet) and measuring the emission or absorption.

Polarography requires measuring the change in the current through an electrochemical cell (see Electrochemistry) containing the solution of interest, as the voltage is varied.

 

Natural Sources of Inorganic Chemicals

 

Why synthesize a compound if you can isolate it from nature? Many useful compounds occur as minerals in rocks. Minerals are mostly ionic compounds (made of positively and negatively charged ions), and are often classified on the basis of the component anion. The most common classes of minerals are, in descending order of abundance:

silicates

carbonates/nitrates/borates

sulfates/chromates

halides

oxides/hydroxides

sulfides

phosphates/arsenates/vanadates/antimonates/molybdates/tungstates

native elements

organic minerals.

("Minerals," Wikipedia).

Oxides and hydroxides can be found pretty much anywhere, in rocks which would have been exposed to weathering. Silicates are also widely distributed. Sulfides are usually found in volcanic regions, in so-called hydrothermal deposits. Halides, carbonates, sulfates, nitrates and borates are more likely to be in desert regions, as they are formed in water and precipitated as the water evaporates. Phosphates are derived from the skeletons of marine life, and thus are found in former seabeds.

Other important sources of inorganic compounds are seawater, subterranean brines, natural gas (the main source of helium), air and plants.

 

Chemical Reactions 101

 

There are only so many chemicals which can be found in nature; the rest must be synthesized. The ideal process is the one-step reaction. However, it may be desirable to take a more circuitous path in order to use a more available, cheaper or less dangerous starting material, or to produce a byproduct which is easier to dispose of or even salable in its own right. Other considerations are minimizing the need for special equipment (e.g., high pressure reactors), reducing energy requirements, and increasing production rate.

A reaction may seem good on its face but be impractical because the reactants are too expensive to obtain. For example, aluminum will react with iron oxide to produce aluminum oxide and pure iron, but the cost of the aluminum is greater than the value of the iron. (Kotz 934).

Planning a chemical synthesis requires thinking about the chemical formula of the product and choosing reactants which provide the necessary building blocks by one or more of the basic forms of reaction. Stoichiometry allows us to express the reaction in quantitative form. Le Chatelier's Principle is used to qualitatively predict the effect of a change in concentration, pressure or temperature on the equilibrium state (ultimate degree of completion) of a reaction. Equilibrium constants, electromotive potentials and Gibbs free energy data are used to make more quantitative predictions as to the completeness of a reaction.

Basic Forms of Reactions. Combination reactions (A+B->AB)are most often used to unite elements to make binary compounds (those with just two elements), especially oxides, hydrides, sulfides, nitrides, phosphides and halides. This tends to be most practical when the elements can be cheaply obtained.

Combination reactions are also used to convert oxides to carbonates (by adding carbon dioxide), nitrates (by adding nitrogen oxide), and sulfates (by adding sulfur oxide), or to hydrate (add water) to a compound.

The simplest and most important decomposition reaction (AB->A+B) is electrolysis, in which a compound made of several ions is dissociated into its component ions. The various combination reactions can also be reversed.

Double displacement reactions (AB+CD -> AD + CB) occur between ionic compounds, but are only useful if the reaction is driven forward by the "disappearance" of one of the products; see Le Chatelier's Principle, below.

A redox reaction is one in which one atom or group gains electrons (reduction) and another loses electrons (oxidation). There are many inorganic compounds which comprise a positively charged metal ion. If the metal ion is reduced to the point that it is electrically neutral, then you have obtained the elemental metal. This is the one of the goals in metallurgy.

If any of the reactants or products in a combination, decomposition, or single replacement (AB + C -> AC + B, or -> CB + A) reaction is an element then the reaction is a redox reaction. A double replacement reaction is a redox reaction if any of the atoms changes its oxidation state (e.g., iron from +2 to +1).

Tables of reduction potentials can be used to predict whether a particular redox reaction will occur spontaneously, or needs to be driven by an applied voltage (see "Electrochemistry").

The most important single replacement reactions are those in which one of the reactants is a free metal or a halogen molecule. The more reactive metal displaces the less reactive one (e.g., copper + silver nitrate -> copper nitrate + silver), the more reactive halogen displaces the less reactive one (e.g., bromine + potassium iodide -> potassium bromide + iodine). The goal may be to make the new salt, to reduce the less reactive metal to elemental form, or both.

We can determine which metal or halogen is more reactive by inspecting a table of reduction potentials; the list of metals, from most active to least, is called the electromotive series.

Stoichiometry. Knowing the chemical formulae of the reactants and products, we can "balance" the equation of a chemical reaction, e.g., know that "x" molecules of compound 1 (#1) react with "y" molecules of #2 to make "m" molecules of #3 and "n" molecules of #4. And that in turn means we don't have to guess how much of compound #1 to add in order to fully react it with #2. And likewise we can calculate the theoretical yield of #3 and #4, given the amounts of #1 and #2 provided.

Le Chatelier's Principle. If a chemical system is in equilibrium, and a variable (pressure, temperature, concentration of reactant or product) is changed, the equilibrium shifts to resist the change. This has a number of interesting implications:

1) if the chemical reaction is chosen so that one of the products is

—insoluble, and thus precipitated out of the solution,

—a gas, and so escapes the solution

then the reaction will be driven forward as the system shifts to try to replace the "lost" products.

2) In a reaction of ionic compounds, if one of the products (ion combinations) is a compound which is itself a poor electrolyte (a compound which only minimally dissociates into ions, such as water), then its component ions are "depleted" which drives the reaction forward.

3) the chemist can shift the equilibrium of the reaction forward (toward the products)

—by adding one of the reactants in excess.

—if any of the reactants or products are gases (e.g., hydrogen, oxygen, carbon dioxide, ammonia), and there are more molecules of gas on one side of the reaction than the other, the equilibrium can be shifted in one direction or another by a suitable change in pressure (see Pressure Control, below).

—by a suitable change in temperature (see Temperature Control, below)

by "coupling" it to a second reaction—a starting material of which is a product of the first reaction—so the second reaction helps pull the first one forward.

Chemical Equilibrium. Many chemical reactions are reversible, that is, they can proceed in either the forward or reverse directions. If the forward and reverse reaction rates are equal, an equilibrium can occur, in which the reaction is incomplete, but there is no further propensity toward change in the concentrations of the reactants and the products. The equilibrium relationship can be expressed quantitatively as a concentration-dependent ratio which equals an equilibrium constant. (The equilibrium constant is also dependent on temperature and sometimes also on pressure.) Once the equilibrium constant is determined for one set of concentrations of the particular reactants and products, the equilibrium formula can be used to calculate the changes in the concentration of the product if the concentrations of the reactants is changed.

Thermodynamics/Gibbs Free Energy. There are reference books in Grantville (e.g., the CRC Handbook of Chemistry and Physics) which have tables of thermodynamic values for various elements, cations, anions and solids. You can use these tables to predict whether a reaction involving those entities can occur spontaneously.

Rate. Loosely speaking, the equilibrium is the endpoint of a chemical reaction, and rate is how quickly it gets there. For a reaction to be commercially feasible, it must not only have an equilibrium favoring the products, it must have a high enough reaction rate. Unfortunately, the prediction of reaction rate is difficult and at the very least requires a knowledge of the exact reaction mechanism. Reaction rates increase with concentration (more chance for the reactants to collide) and temperature. Reactions of ions in solution tend to be fast. Other reactions are slower, as some (but not all) of the bonds holding the reactants together will need to be broken.

Planning. In general, synthetic strategies depend on either displacing one metal with another which is higher in the electromotive series, or on causing two soluble salts to react to form an insoluble product, a gas, or water. (See appendix table 1-2.)

 

Electrochemistry

 

Electrochemistry studies the use of spontaneous chemical reactions to create an electric current (as in a battery) or the use of an applied electrical voltage to force a chemical reaction to occur (as in an electrolytic cell).

If the electromotive potential of a reaction is less than zero, then the reaction won't occur spontaneously. But you can still make it happen by applying electricity. The voltage has to be high enough to counteract the negative potential of the reaction, and the current will determine how much product is produced. The reaction will not be 100% efficient, so you will have to use more current than what is theoretically required.

An electrolytic cell has an electrolyte and two electrodes (cathode and anode). The electrolyte may be a solution or a molten salt; the key point is that it contains mobile ions. An ion is an atom or molecule which has lost one or more electrons giving it a positive charge (cation), or gained one or more electrons, yielding a negative charge (anion). The voltage drives the movement of cations toward the cathode, where they are reduced, and of anions toward the anode, where they are oxidized.

At the anode and cathode, the products may undergo further reaction to form secondary products. In a two compartment diaphragm or membrane cell, some kind of barrier prevents undesired reactions between anode and cathode species. For example, in the chloralkali process, hydroxide ions are allowed to react with sodium ions in the cathode compartment (making caustic soda), but not with chloride ions in the anode compartment. And recombination of sodium and chloride ions is also inhibited.

In 1633, Dr. Phil built a "wet cell" battery with a dilute sulfuric acid electrolyte and a zinc electrode. Offord, "Dr. Phil Zinkens a Bundle" (Grantville Gazette 7). That story doesn't reveal the identity of the second electrode, but it would probably be copper, see Boatright, "So You Want to Do Telecommunications in 1633?" (Grantville Gazette 2).

Here, we are more concerned with electrolysis, which is the decomposition of a chemical by electricity. Dr. Gribbleflotz experimented with electrolysis of an unspecified salt in Offord and Boatright, "The Dr. Gribbleflotz Chronicles, Part 2: Dr. Phil's Amazing Essence Of Fire Tablets" (Grantville Gazette 7)

In the old time line, water was decomposed into hydrogen and oxygen in 1800; sodium and potassium were isolated by electrolysis of their salts in 1807.

The first electrochemical reaction of industrial importance was probably in the purification of platinum. In 1991, the principal electrochemical products were caustic soda, chlorine, aluminum, copper, zinc, chromium, sodium chlorate, caustic potash, magnesium, sodium, manganese dioxide, permanganates, manganese, perchlorates, and titanium. (KirkOthmer9:125). The most common electrolyte was probably sodium chloride.

Electricity is supplied by power plants as high voltage alternating current, but for electrochemical use, this needs to be rectified into direct current and stepped down by transformers to a lower voltage.

 

Catalysts

 

What appears to be a single reaction may occur through a series of steps (addition, elimination, substitution and rearrangement), each with its own molecularity (the number of reacting molecules) and own rate law (a mathematical relationship between the rate of the reaction step and the concentration of the reactants). The slowest step determines the rate of the overall reaction.

Catalysts increase (or decrease, so-called negative catalysts) the rate of a chemical reaction without participating in the net reaction. They have no effect on the equilibrium concentrations of the reactants and products.

Johann Dobereiner discovered that the rate of the conversion of alcohol to acetic acid (1816) or acetic aldehyde (1832) could be increased by conducting the reaction in the presence of platinum wire. He created (1823) a lighter in which the hydrogen flame was produced by the action of sulfuric acid on zinc, in the vicinity of a platinum sponge (EA "Dobereiner"; Jentoft). In 1817, Humphrey Davy studied the effect of wires of different metals on the rate of reaction of coal-gas with oxygen. The term "catalysis" was coined by Jons Jakob Berzelius, who used it to explain additional phenomena, including the rapid decomposition of hydrogen peroxide by metals.

EA "Catalyst" says that "many common catalysts are powders of metals or of metallic compounds," and by way of example mentions that platinum catalyzes the hydrogenation of double bonds. It also indicates that acids can be catalysts; "sulfuric acid catalyzes the isomerization of hydrocarbons."

EA "Platinum" says that for use as a catalyst, platinum is used in powdery ("platinum black", from reduction of platinum chloride) or spongy form, and there is reference to its use in production of nitric acid.

Further "data mining" EA will identify other catalysts, which I have tried to logically group below:

metals: palladium, neodymium, samarium, rhenium, lutetium, ruthenium, molybdenum, silver, mercury, nickel, iron, rhodium, a platinum-rhodium alloy (for preparation of hydrocyanic acid from ammonia, methane and air, or preparation of nitric acid or ammonium nitrate), copper, unidentified transition metals,

metal oxides: iron oxide (to catalyze the direct combination of nitrogen and hydrogen in the Haber Process, EA "Ammonia") , manganese dioxide (to speed the thermal decomposition of potassium chlorate to produce oxygen, EA "Chemical Reactions"), platinum dioxide (from fusion of chloroplatinic acid with sodium nitrate), copper oxides, chromium zinc oxide (used in methanol production), scandium oxide,cadmium oxide, lead oxide (litharge),

acids: hydrobromic acid, chromic acid, hydrogen fluoride, hydrochloric acid (for nitrobenzene),

miscellaneous: copper acetate, aluminum chloride, certain organotin compounds, nickel-aluminum sulfide, sodium nitrate (for manufacture of sulfuric acid), sodium ethylate, peroxides, hot alcoholic solution of potassium cyanide, lithium acetate, n-butyllithium, coordination compounds of zirconium, phosphorus pentaflouride, water (!).

EA apparently overlooks the organometallic catalysts, which were rather important in the late twentieth century.

It is important to note that many catalysts are reaction-specific. Hence, there is going to be a lot of educated trial-and-error going on; systematically testing the effect of each of a series of potential catalysts to see if any of them facilitate a reaction of interest.

A good example of this is the screening carried out by Bosch to make the Haber nitrogen fixation process feasible commercially. Haber initially identified osmium and uranium, both of which were quite expensive, as effective catalysts. Bosch set up test reactors, and tested 4,000 different catalysts over five years, finding that an impure iron oxide catalyst was cheap and operable. (McGrayne 66; KirkOthmer5:323).

Just to complicate matters further, modern catalysts aren't necessarily simple materials. Because the catalytic material is expensive, it is usually advantageous to use it in small amounts, and disperse it on a support material with a high surface area. Gamma-alumina is the most popular support. (KirkOthmer 5:347).

There are also catalytic promoters. These are substances which don't act as catalysts themselves, but which potentiate the activity of the "real" catalyst. There are both chemical promoters which change the surface chemistry, and textural promoters which alter the physical characteristics. Alkali metals have been used as chemical promoters.

Catalysts can be deactivated as a result of fouling (they are physically masked by deposited material), poisoning (feed impurities which reduce their catalytic activity), and physical change (e.g., sintering). Catalysts may in turn be regenerated.

The modern catalyst for ammonia synthesis is a combination of iron oxide as the catalyst, aluminum and calcium oxide as textural promoters, and potassium as a chemical promoter.

Some catalysts—common acids, finely divided metals (e.g. platinum), and some metal oxides—can be put to work in the 1632verse in fairly short order. Others are rare materials, or of a complex composition or structure, and it will take years, if not decades, of work to duplicate them.

Temperature Control

 

Temperature affects both the rate and the completeness of a reaction. A typical rule of thumb is that for every 10̊C increase in temperature, the reaction rate will double. The effect of the temperature on the completeness of a reaction depends on whether it is endothermic (needs heat) or exothermic (releases heat). Higher temperatures favor endothermic reactions and hinder exothermic ones.

There are other considerations. Too high a temperature can result in side reactions, including decomposition. So, depending on the reaction, you may want to heat things up, keep the temperature from increasing above a certain point, or bring it below room temperature.

If a reaction is temperature sensitive, then you need a good thermometer. For industrial work, you might prefer a thermostat which controls a heating or cooling device. In 1634, the Essen Instrument Company is manufacturing precision mercury thermometers. (Mackey, "Ounces of Prevention," Grantville Gazette 5). I would expect that simple spirit thermometers are being made, too.

Both heating and cooling processes are slower to start, and stop, when the reaction is on an industrial scale. As the volume increases, the ratio of the heating or cooling surface to the volume decreases.

In the laboratory, if an elevated temperature is needed for a reaction, the chemist will use a gas-burning Bunsen burner. This can reach a temperature close to 900̊C. Up-time, natural gas is used, but Dr. Phil has an alcohol burner in 1633. Offord and Boatright, "Dr. Phil's Amazing Essence of Fire Tablets," Grantville Gazette 7).

On the industrial scale, you may be burning some kind of fuel, which heats air or water surrounding the vessel, or passing through tubes in the vessel. Steam distillation falls in this category. Or you may be converting electrical energy into heat energy. Or running two industrial processes alongside each other, one providing heat for the other.

Chemical reactions tend to be more efficient when the reactants are all in the liquid phase. Solids react only at their surfaces, and gases are low in density. If one of the reactants is solid at room temperature, then to put it in the liquid phase, it must be dissolved or melted. And melting requires heat.

In some cases, it is possible to drastically lower the melting point of the substance of interest by adding a second substance, known as a "flux". Sodium, potassium and lead oxides lower the melting point of glass from 1700° C. to perhaps 900-1200. Aluminum oxide melts at 2054° C., but it can be dissolved in cryolite, which is molten at a little less than 1000° C.

You may also be trying to lower the melting point of the waste material. For example, in smelting copper, you may want to make sure that the silica forms a very liquid slag, that the copper can sink through. So iron oxide is added.

Smelting metals typically requires a reducing agent (e.g. carbon) and heat. For tin or lead oxide, a campfire (600-650°C) is good enough, but copper requires a temperature of 700-800 and forgeable iron, 1100°C.

Combustion processes cannot exceed the "adiabatic combustion temperature," which, for combustion in air, is about 2000° C for natural gas, 2150 for oil and 2200 for coal. The fuel is the source of carbon and the air is the source of oxygen. The limiting temperature is a function of the heating value of the fuel, the specific heat capacity of the fuel and the air (and the combustion products), the ratio of fuel to air, and the air and fuel inlet temperatures (Wikipedia, "Combustion"). Even higher temperatures are achievable with rocket engine fuels/oxidizers.

The practical combustion temperatures for industrial chemistry are much lower than the theoretic limit. It is difficult to achieve complete combustion if there is insufficient air, heat is lost (radiated out; carried away by exhaust gases), and so forth. To ensure complete combustion, it is customary to use an excess of air, but air dilution then reduces the temperature of combustion.

In 1920, a coal furnace could achieve a temperature of 1600°C without a blast, and 1800°C with one. A gas-fired furnace, with hot air, both the gas and air under pressure, could reach about 2000°C. (Marsh, 46). For higher temperatures, you need to heat by means other than combustion.

An electric arc furnace uses an electric current to heat a conductive material. That could be an ionic compound, or a conductive metal. Perhaps the first industrial use of the electric arc furnace was in the production of calcium carbide by heating lime and coke to 2000°C (1888). Electric arc furnaces came to play an important role in small-scale steelmaking.

Another option for sidestepping the practical combustion temperature limit ...