The Production of Useful Chemicals

Recent advances in biotechnology have resulted in improved fermentation processes for the production of useful chemical intermediates. One such process was developed a few years ago during the U.S. DOE sponsored CRADA (Cooperative Research and Development Agreement) with Applied Carbochemicals (ACC). Under this CRADA a consortium of four national labs including Argonne National Laboratory (ANL), Oak Ridge National Laboratory (ORNL), National Renewable Energy Laboratory (NREL), and Pacific... 

Electrocatalytic processes have been used for the production of useful chemicals, for instance, N2O and NH2OH from nitrates. 

Due to its importance with regsird to the production of useful chemicals by selective oxidation and to its role in abnormal combustion phenomena such as knock and run on in the internal combustion engine, the spontaneous combustion of hydrocarbons in the temperature range 200—600 °C has been the most widely studied mode of oxidation. This Chapter, therefore, has a number of aims. First, the generally accepted theories for the mechanism of spontaneous combustion at the beginning of the 1960 s will be briefly surveyed. A detailed discussion of current... 

Though most of the applications of membrane reactors that we have discussed so far involve the production of useful chemicals some of the most interesting applications currently imder consideration relate to energy production, transfer and utilization. High temperature membrane reactors are, for example, being looked upon in the context of Chemical Energy Transmisssion Systems (GETS). 

Gas formers—for the production of useful chemical entities such as respirable oxygen. 

Because the free enthalpy change in this type of reaction is virtually zero, the result at equilibrium is a random distribution of the alkylidene groups. Thus, starting with methyl oleate, the equilibrium mixture consists of 50 mol% of the starting material and 25 mol% of each of the products 9-octadecene and dimethyl 9-octadecene-1,18-dioate. The cis/trans ratio of the reaction products is also in accordance with thermodynamics. This demonstrates that - in the presence of a suitable catalyst - the metathesis of unsaturated fatty acid esters provides a convenient and highly selective route to unsaturated diesters. Unsaturated diesters are important intermediates for the production of useful chemical products such as macrocyclic compounds. For instance, the diester obtained by metathesis of ethyl oleate has been subjected to a two-step reaction sequence, i.e. a... 

Chemical reactions keep both our society and our own bodies going (4.7). Ninety percent of our society s energy is derived from chemical reactions, primarily the combustion of fossil fuels. Our own bodies derive energy from the foods we eat by orchestrating a slow combustion of the molecules contained in food. The products of useful chemical reactions can sometimes present environmental problems. For example, carbon dioxide, one of the products of fossil-fuel combustion, may be causing the planet to warm through a process called the greenhouse effect. 

The July 1995 issue of the Journal of Chemical Educa t/on (pp 659-661) contains an undergraduate laboratory experiment in which COSY is used to analyze the products of a chemical reaction... 

NMR IR UVVIS and MS) were obtained using pure substances It is much more common however to encounter an organic substance either formed as the product of a chemical reaction or iso lated from natural sources as but one component of a mixture Just as the last half of the twentieth cen tury saw a revolution in the methods available for the identification of organic compounds so too has it seen remarkable advances in methods for their separation and purification... 

Calcium carbide has been used in steel production to lower sulfur emissions when coke with high sulfur content is used. The principal use of carbide remains hydrolysis for acetylene (C2H2) production. Acetylene is widely used as a welding gas, and is also a versatile intermediate for the synthesis of many organic chemicals. Approximately 450,000 t of acetylene were used aimuaHy in the early 1960s for the production of such chemicals as acrylonitrile, acrylates, chlorinated solvents, chloroprene, vinyl acetate, and vinyl chloride. Since then, petroleum-derived olefins have replaced acetylene in these uses. 

Natural gas Hquids represent a significant source of feedstocks for the production of important chemical building blocks that form the basis for many commercial and iadustrial products. Ethyleae (qv) is produced by steam-crackiag the ethane and propane fractions obtained from natural gas, and the butane fraction can be catalyticaHy dehydrogenated to yield 1,3-butadiene, a compound used ia the preparatioa of many polymers (see Butadiene). The / -butane fractioa can also be used as a feedstock ia the manufacture of MTBE. 

Pseudomonads also have the abiUty for xenobiotic metaboHsm and are capable of carrying out diverse sets of chemical reactions. Pseudomonas species is used ia the commercial productioa of acrylamide (qv) (18). Several operoas iavolved ia the metaboHsm of xeaobiotic compouads have beea studied. Use of Pseudomonads for the clean up of the environment and for the production of novel chemical iatermediates is likely to be an area of active research ia the 1990s. 

Sodium iodide [7681-82-5] Nal, mol wt 149.92, mp 662°C, 84.66% I, forms colorless cubic crystals, which are soluble in water, ethanol, methanol, and acetone. It is used in photography, for the production of organic chemicals, and as an expectorant in cough medicines. Nal is separated by addition of sodium hydroxide or sodium carbonate to an acidic iodide solution (see also Expectorants, antitussives, and related agents). 

Formaldehyde. Worldwide, the largest amount of formaldehyde (qv) is consumed in the production of urea—formaldehyde resins, the primary end use of which is found in building products such as plywood and particle board (see Amino resins and plastics). The demand for these resins, and consequently methanol, is greatly influenced by housing demand. In the United States, the greatest market share for formaldehyde is again in the constmction industry. However, a fast-growing market for formaldehyde can be found in the production of acetylenic chemicals, which is driven by the demand for 1,4-butanediol and its subsequent downstream product, spandex fibers (see Fibers, elastomeric). 

This process or a variation called the Hargreaves process is also used in areas where sulfuric acid is available as a by-product or where co-product HCl is needed for the production of other chemicals. 

Approximately 600,000 metric tons of aluminum hydroxides were used in chemical appHcations in the United States in 1988 40% as fillers, 45% for the production of aluminum chemicals, and 15% for various other uses. Carpet backing was the principal filler type appHcation foUowed by polyester products. 

Chemical. The use of isopropyl alcohol as a feedstock for the production of acetone is expected to remain stable, as the dominant process for acetone is cumene oxidation. Isopropyl alcohol is also consumed in the production of other chemicals such as methyl isobutyl ketone, methyl isobutyl carbinol [108-11-2] isopropjlamine, and isopropyl acetate. The use of diisopropyl ether as a fuel ether may become a significant oudet for isopropyl alcohol. 

Cyanohydrins are used primarily as intermediates in the production of other chemicals. Manufacture of methyl methacrylate, used to make acrylic mol ding resins and clear sheet, eg, Plexiglas acrylic sheet, from acetone cyanohydrin is the most economically important cyanohydrin process (see Methacrylic polymers). Cyanohydrins are also used as solvents in appHcations including fiber-spinning and metals refining. Cyanohydrins and derivatives reportedly act as antiknock agents in fuel oil and motor fuels and serve as electrolytes in electrolytic capacitors. 

Industrial ethanol is one of the largest-volume organic chemicals used in industrial and consumer products. The main uses for ethanol are as an intermediate in the production of other chemicals (Table 8) and as a solvent. As a solvent, ethanol is second only to water. Ethanol is a key raw material in the manufacture of dmgs, plastics, lacquers, poHshes, plasticizers, perfumes, and cosmetics. Around 1960, manufacture of ethanol was the top consumer of ethylene in the United States, but since 1965 it has rated below manufacture of ethylene oxide and polyethylene. 

Dissociation extraction is the process of using chemical reac tion to force a solute to transfer from one liquid phase to another. One example is the use of a sodium hydroxide solution to extract phenolics, acids, or mercaptans from a hydrocarbon stream. The opposite transfer can be forced by adding an acid to a sodium phenate stream to spring the phenolic back to a free phenol that can be extrac ted into an organic solvent. Similarly, primary, secondary, and tertiary amines can be protonated with a strong acid to transfer the amine into a water solution, for example, as an amine hydrochloride salt. Conversely, a strong base can be added to convert the amine salt back to free base, which can be extracted into a solvent. This procedure is quite common in pharmaceutical production. 

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