Grantville Gazette Volume 27

by edited by Paula Goodlett

  Pentosans. Pentosans are polymers of arabinose and other five-carbon sugars. They can be isolated from oat hulls, corn cobs, sugar cane stalks, wood, and other sources. Acid treatment produces furfural, which as previously mentioned, is used in the petrochemical industry. (Wittcoff 144; EA/Furfural). And from corn cobs, you get acetic and formic acid as byproducts.

  Starch. Starch, a composite of amylose and amylopectin, is obtained from corn, rice, potato, wheat, tapioca, arrowroot, and sago. It can be used as is, derivatized, or acid-hydrolyzed to generate glucose. Glucose, in turn, can be converted to gluconic acid, sorbitol or alpha-methyl glucoside.

  Resins. Since antiquity, tree resins (e.g., the Biblical frankincense and myrrh) have been distilled to separate them into turpentine (the distillate) and rosin (the solid residue). A pine tree might yield 10 pounds gum, which in turn yields 81% rosin and 19% turpentine (EA/Turpentine).

  Turpentine can be used as a solvent, or as a source of starting materials for the synthesis of various flavors and fragrances. The rosin can be cooked to yield pitch. (Dunwody 127).

  Chemically, resins are mostly terpenes, which are related to isoprene (the alkene of natural rubber). However, the Jeffrey Pine and Gray Pine are sources of almost pure n-heptane, an alkane. Resins may also contain resin acids.

  Essential oils are volatile, fragrant liquids isolated from various parts of plants, usually by distillation or solvent extraction. Almond oil is from a seed, sassafras from a bark, camphor from a wood, ginger from a rhizome, peppermint from a leaf, frankincense from a resin, clove from a flower, lemon from a fruit peel, and valerian from a root. The crude liquids were used in folk medicine and cosmetics.

  These oils are mixtures of organic chemicals, including terpenes, camphors, alcohols, phenols, ethers, aldehydes, ketones, esters, and organic acids, and separation is possible. Sometimes one constituent predominates, menthol is about 30-50% of peppermint oil (Gildemeister 643). But the chemicals which give the essential oil its characteristic fragrance aren't necessarily present in large proportions; the "rose ketones" are less than 1% of attar of roses, but provide about 90% of its "odor content" (Wikipedia/"Rose Oil").

  Oleochemicals. Vegetable fats (solids) and oils (liquids) are rich in triglycerides (triacylglycerols). A bit of chemical nomenclature is appropriate here. Glycerol is an alcohol. Alcohols are compounds comprising at least a hydroxyl (-OH) group connected to a carbon atom. In glycerol, there is a three carbon chain (like that of propane), and there is a hydroxyl attached to each carbon atom.

  In a triglyceride, each of the hydroxyl groups is esterified, which means that the hydroxyl group is replaced with a "fatty acid" group. A fatty acid is a kind of "carboxylic acid"; the latter have the form HO-C(=O)-R. In a fatty acid, the R group is a long unbranched aliphatic hydrocarbon.

  In soap making, the fats (triglycerides) are saponified, that is, hydrolyzed (reacted with water) in the presence of a strong base (usually sodium hydroxide, potassium hydroxide or sodium carbonate). The water cleaves the ester (-O-C(=O)-) bonds, producing a mixture of the free fatty acids, together with glycerol. Common salt is added to precipitate the mixture as soap.

  The soapmakers don't separate these mixtures. However, the organic chemical industry can isolate the individual fatty acids by distillation or other means. It's possible to obtain, in purity exceeding 90%, straight chain fatty acids of carbon numbers 6, 8, 10, 12, 14, 16 and 18 (M&B 584). These fatty acids, in turn, can be converted to fatty alcohols, or reduced to the corresponding simple alcohol by treatment with lithium aluminum hydride (M&B 604). Or they can be esterified and the ester reduced to a simple alcohol (M&B 683).

  Fatty acid composition varies from plant to plant. That is because they contain different triglycerides. Moreover the triglycerides aren't necessarily simple glycerides in which the three fatty acid groups are identical; they may be "mixed" glycerides. The fatty acid compositions of coconut, corn, cottonseed, olive, palm, palm kernel, peanut, soybean, linseed and tung oil are given in M&B 684. EB11/Oils sets forth plant or animal sources for each of 32 different fatty acids.

  You can obtain about 5 gallons of castor oil from 100 pounds of castor oil (Ricinus communis) seeds. (EB11/Castor Oil). The fatty acids of castor oil are about 85% ricinoleic acid, a triol which can be reacted with isocyanate to make polyurethane. (SzmantIURR 60).

  The glycerol byproduct is also of some interest, as it can be used in the manufacture of nitroglycerine.

  Plant Juices are liquids found as such in fruit or vegetable tissue. From 1860 to 1919, lemon juice was used as a source of citric acid. (Wikipedia/"Citric Acid"). Likewise, malic acid can be produced from apple juice.

  Other botanochemicals include alkaloids (e.g., atropine), tannins, terpenoids (e.g., artemisinin, an antimalarial), glycosides, and proteins. Typically, the exotic botanochemicals are obtained from a particular part of a particular plant, and separated from other chemicals by a combination of distillation, solvent extraction, and recrystallization.

  Conversion by Destructive Distillation (Pyrolysis). Like coal and petroleum, plant matter can be pyrolyzed (heated in absence of air) so as to decompose the botanochemicals into simpler forms. Wood was pyrolyzed by the ancient Egyptians and their embalming fluid included methanol.

  In this time line, methanol was so isolated by Boyle (1661), and acetic (pyroligneous) acid by Glauber (1648). The acetic acid is readily converted to acetone.

  The destructive distillation of wood at 400oC yields methanol (1.5-2.5%), acetic acid (3-7%), charcoal (31-41%), wood tar (11-19%), and gases (hydrogen, carbon monoxide, carbon dioxide, methane) (15-17%). (Kirk-Othmer 25:651; cp. Mills 27; Abraham 184-190; Bordwell 58; Sadtler 350).

  The result depends on the species of wood and the temperature employed. Hardwoods produce more acetic acid and methanol than soft woods, but the softwoods produce more wood tar. (Sjostrom 235). EB11/Tar says that pine (a softwood) was favored.

  The wood tar (turpentine) can be used for waterproofing, or in theory it can be further fractionated to recover fatty acids, phenol, cresols, guaiacol, and other aromatic compounds. However, such fractionation was not often done commercially in this time line.

  Conversion by Fermentation. Plant material rich in carbohydrates, e.g., molasses, can be used as nutrients in fermentation processes. You need a microorganism which will produce the chemical of interest. The advantage of fermentation processes is that they don't require massive amounts of energy. However, isolating the product can be laborious.

  Down-timers ferment grapes to make wine, and barley to make beer. Both are dilute solutions of ethyl alcohol. However, the alchemists know how to distill it to high purity (~95%), calling it aqua ardens("burning water").

  Wine is perhaps 12% ethyl alcohol, 85% water, and 3% everything else. In red wines, the "everything else" is primarily glycerol, organic acids (tartaric, malic, citric, succinic), and phenols.

  "Fusel oil" refers to the dregs left when the liquor of fermented grain, potatoes, molasses, etc. are distilled. It contains longer alcohols, notably amyl (C5) alcohols, and in some cases also propyl (C3) and butyl (C4) alcohol. (EB11/Fusel Oil). They arise by decomposition of amino acids (SzmantIURR 37).

  While the wine yeast convert sugar into ethyl alcohol, other organisms make other chemicals. For example, Clostridium acetobutylicum ferments starch to yield 60% n-butyl alcohol, 30% acetone and just 10% ethyl alcohol. This was the World War I Weizmann process, and the acetone was needed to make smokeless powder. The butyl alcohol, originally a worthless byproduct, later became useful in the manufacture of butyl acetate(EA/Alcohols) and consequently more valuable than the acetone. (M&B 506).

  For antibiotic production, the most important OTL organisms were Streptomyces (bacteria found in soil and decaying vegetation), Cephalosporium (fungus), and Penicillium (mold). It's perhaps worth noting that molds are used in folk medicine, and it would be prudent to identify them and culture them out.

  It is difficult to predict in advance which fermentation
organisms and processes we will discover when, but if we don't screen (culture soil and water organisms on culture media and see what they produce), we won't find new antibiotics.

  Zoochemical Feedstocks

  Rendering separates the animal carcass into fat, protein and bone. Down-time, animal fats were used for soap and candle making. Like vegetable fats and oils, animal fats and oils can be used as a source of triglycerides and their derivatives. As you would expect, they have their own characteristic complement of fatty acids. The fatty acid compositions of beef tallow, butter, lard, and cod liver are given in M&B 684.

  In late-nineteenth century practice, fatty matter was extracted from bones with benzene or carbon disulfide for use as soap stock. The remaining material was distilled, and separated into ammonia, "bone oil," and "bone black." For the organic chemist, the bone oil is of greatest interest; it contains pyrrole, pyridine, picoline, lutidine, collidine, and quinoline. These are heterocyclic aromatic compounds. (Thorp, 281).

  Mills (174) says that horn, hair and leather, when destructively distilled, yield a liquid distillate similar to that from bones.

  Animal protein can be hydrolyzed to obtain the twenty genetically encoded amino acids. (That's still the industrial source of L-cysteine, leucine, asparagine and tyrosine.) (Bhat 328).

  Cow's milk is composed primarily of water (87%), protein (casein and albumin, 4.75%), fat (3.5%), carbohydrate (lactose, 4%), and lactic acid, and the milk of other mammals has the same basic ingredients in somewhat different proportions. (EB11/Milk).

  The wool of sheep is a source of both wool fiber (keratin) and wool grease (lanolin) (5-25% wool). Keratin is a protein and thus can be hydrolyzed to yield the individual amino acids. Lanolin, a wax, is a mixture of fatty acids, alcohols, and their esters. Cholesterol (a steroid alcohol) is obtained commercially from lanolin (SzmantIURR 139).

  The exoskeletons of crustacea and insects are a source of chitin, a polysaccharide. Chitin can be deacetylated to yield chitosan or hydrolyzed to yield glucosamine.

  Miscellaneous Inorganic Feedstocks.

  It is also possible to make use of inorganic carbon sources other than coal, such as the carbonates, and the gases carbon monoxide or carbon dioxide. Phosgene (COCl2), a useful albeit toxic reagent, is made by combining carbon monoxide with chlorine at 200oC (M&B 923). Cyanides can be obtained from certain plants (bitter almonds, cassava, appleseeds) or made from other inorganics.

  Dude, Where's My Carbon Skeleton?

  Ideally, we keep our syntheses simple. That generally means using, if available at a reasonable price, a starting material which has the same carbon skeleton as our intended product.

  Even better, the starting material should be one of the chemicals readily obtainable by processing a "natural feedstock" available in USE territory.

  * * *

  In general, I don't see the lower alkanes (methane, ethane, propane, butane) as preferred C1-C4 building blocks. First, since they're gases, there's a handling problem. For storage and transport, gases must be compressed, and then pumped into either a pipeline or a tank. So you need a pump, and you need pipes and tanks which can withstand the pressures involved. For cars, natural gas is usually compressed to about 200 times atmospheric pressure. The alternative to simply compressing a gas is to liquefy it, by putting it under moderate pressure and then cooling it below its melting point. You can liquefy crude natural gas (mostly methane; LNG) or petroleum gas (propane and/or butane; LPG).

  In fall 1631, when Vicky Emerson told the gas oven investors how "difficult it was to compress natural gas and store it" (Goodlett and Huff, "Poor Little Rich Girls," Grantville GazetteIV), she wasn't lying. What she didn't tell them was that she expected the compression problem to be solved within two or three years. The tanks could be made of copper or steel. (Ashby 143).

  Until the compression problem was solved, the organic chemical industry could fractionate natural gas, but it would have to do so near the wellhead, and, on the spot, process the alkanes into something which would be liquid at room temperature, such as methyl alcohol, or ethyl, propyl or butyl bromide.

  The second problem is that because alkanes aren't very reactive, there isn't much that can be done with them directly. We have the option of converting methane into "synthesis gas" (carbon dioxide and hydrogen). Otherwise, the derivatives most likely to be produced, for conversion into other products, are alkyl chlorides and bromides. Without ultraviolet radiation, you need 250-400oC. With the assistance of UV, we can chlorinate methane, ethane or propane at room temperature, but in the last case, we obtain a nearly equal mixture of n-propane and isopropane. Bromination of propane requires UV treatment at 127oC, but is highly specific for isopropane. (MB 38-40, 116-122) I would expect similar patterns of isomer production as a result of chlorination or bromination of butane.

  * * *

  I see the preference as being in general for alkenes (from cracking of petroleum), alcohols and organic acids (from fermentation or destructive distillation of biological feedstocks), and simple aromatics (from pyrolysis of coal). But the exploitation of petrochemicals is dependent on both the development of oil supplies beyond that needed to satisfy fuel demands and on the realization of the necessary processing technology.

  So, here're my best guesses as to what the organic chemical industry will use as its basic building blocks, and when they will be available. In general, these building blocks are primary chemicals; they are isolated from processed natural feedstocks, rather than synthesized by reaction of pure chemicals. But of course it's possible to make the larger building blocks by combining smaller ones.

  C1 aliphatic: Perhaps by late 1631, but certainly by 1632, we will producing methanol by destructive distillation of wood. Methanol can be converted into methyl halides, formaldehyde, formic acid, methylamine. Formic acid can instead be obtained by distillation from the bodies of dead ants. (Gmelin VII-271). There are also the inorganic C1s, carbon monoxide and dioxide, but those are mostly used when you want to keep the C=O bond, as in aldehydes and ketones. And there is coke, the progenitor for the carbides, cyanides and related salts, cyanamide, urea, and thiourea.

  C2 aliphatic. In 1631—within days after the grocery store runs out of whiskey—we will be distilling ethyl alcohol. Ethanol can be converted into ethylene, ethyl halides, ethylamine, acetaldehyde, and acetic acid. Acetic acid is an alternative C2; it is distilled from vinegar. And there is the possibility of making acetylene, too. Some years later, these will be supplanted by ethylene from steam cracking of petroleum.

  C3 aliphatic. There are actually two C3 skeletons, the linear (n-propyl) and branched (isopropyl). The likeliest linear C3 building blocks are acetone (from destructive distillation of wood or, eventually, a Weizmann process fermentation), n-propyl alcohol (from the fusel oil of, e.g., the marc brandy from southern France; EB11/Fusel Oil) These could be available in 1631-32, but 1632-33 is more likely. Other possible building blocks include lactic acid and glycerol (Dimian 439), and propionic acid (by fermentation of molasses, yielding about 10%, or destructive distillation of wood, yielding 2-4%; Molinari 348) . In the longer term, we will probably use propylene.

  Isopropyl alcohol is not readily available by fermentation. (Meldola 64). However, it can be made by reduction of acetone (M&B 636), and, eventually, hydration of propylene.

  C4 aliphatic. There are two different isomers of C4, linear and branched, and two different ways of connecting a single functional group (R) to the carbon skeleton, so we have four different butyl functionalities: n-, iso- , sec- and tert-butyl. We ignore the latter two.

  The most likely C4 building blocks are butyl alcohol and butyric acid. Isobutyl alcohol is found in fusel oil, such as that from fermented potato (EB11/Butyl Alcohols) or beet-root molasses(EB11/Fusel Oil) . N-butyl alcohol is perhaps obtainable by a "peculiar" fermentation of glycerin (Id.) Figure 1631-33. Some years later, the Weizmann process of making it will come into play.

  N-butyl and isobutyl alcohol (and the corresponding al
dehydes) are made in modern practice by hydroformylation of propylene (in effect, adding a carbon to a C3 building block). This will be impractical for generations in the 1632verse, because the reaction requires a fancy cobalt or iron carbonyl catalyst. (Szmant 350, M&B 507).

  Butyric acid likewise comes in two isomers, with the n-isomer being available from the triglycerides of butter. EB11/Butyric acid says that the iso-form "is found in the free state in carobs (Ceratonia siliqua) and in the root of Arnica dulcis, and as an ethyl ester in croton oil."

  Also in contention, we have several dicarboxylic acids—succinic acid ("spirit of amber"), fumaric acid, malic acid, and levulinic acid. (Dimian 439). Succinic acid can be distilled from amber and various resins, or synthesized by fermentation or oxidation of fats and fatty acids. (EB11/Succinic Acid). "Fumaric acid is found in fumitory (Fumaria officinalis), in various fungi (Agaricus piperatus, &c.), and in Iceland moss." (EB11/Fumaric and Maleic Acids). It can also be obtained by Rhizopus fermentation of carbohydrates (Szmant 362). And it occurs in many plants (EA). Malic acid was first isolated from apple juice in OTL 1778. It's "found abundantly in the juices of many plants, particularly in mountain-ash berries, in unripe apples and in grapes. The acid potassium salt is also found in the leaves and stalks of rhubarb." (EB11/Malic Acid). Levulinic acid is not found in natural feedstocks, but it is obtainable by hot acidification of sucrose. (EB11/Laevulinic Acid).

  C5 aliphatic. A mixture of C5 (amyl) alcohols is obtainable from fusel oil, probably 1631-33. Valeric acid and valeric aldehyde are found in certain plant sources (EB11/Valeric Acid, Valerian).

  C6 aliphatic. One possible source is caproic acid, in butter fat and coconut oil (EB11/Oils). Another is adipic acid (from fat), used as a nylon precursor. Still others are sorbitol (from Sorbus trees) and lysine (from animal protein) (Dimian), but they have multiple functional groups and hence might need to undergo several conversions in order to arrive at the desired product.