TAME

Table 10.8 shows a typical feedstock composition and the average properties of crude or pure TAME. 

Properties of crude mixture of TAME -1- residual C5 cut at 4% methanol ... 

Typical feedstock composition used for tame synthesis. Product performance and properties. 

For many molecules the reduced dipole moment p = (p /( a )) is greater than 1 and the tenns in the successive tenns in the X expansion oscillate widely. Stell, Rasaiah and Narang [M] suggested taming this by replacing the tnincated expansion by the Fade approximant... 

Dimethyl sulfoxide has the structure (CH3)2 —0 and is commonly referred to as DMSO It IS a relatively inexpensive solvent ob tamed as a byproduct in paper manufacture... 

In 1861 Johann Josef Loschmidt who was later to become a professor at the University of Vienna pri vately published a book con taming a structural formula for benzene similar to the one Kekule would propose five years later Loschmidt s book reached few readers and his ideas were not well known... 

Not so for synthesis in the chemical industry where a compound must be prepared not only on a large scale but at low cost There is a pronounced bias toward reactants and reagents that are both abundant and inexpensive The oxidizing agent of choice for example in the chemical industry is O2 and extensive research has been devoted to develop mg catalysts for preparing various compounds by air oxidation of readily available starting materials To illustrate air and ethylene are the reactants for the industrial preparation of both acetaldehyde and ethylene oxide Which of the two products is ob tamed depends on the catalyst employed... 

Suppose you take two flasks one containing pure water and the other a buffer solution mam tamed at a pH of 7 0 If you add 0 1 mole of acetic acid to each one and the final volume m each flask IS 1 L how much acetic acid is present at equi librium How much acetate ion In other words what IS the extent of ionization of acetic acid m an unbuffered medium and m a buffered one ... 

Cation (Section 1 2) Positively charged ion Cellobiose (Section 25 14) A disacchande in which two glu cose units are joined by a 3(1 4) linkage Cellobiose is oh tamed by the hydrolysis of cellulose Cellulose (Section 25 15) A polysaccharide in which thou sands of glucose units are joined by 3(1 4) linkages Center of symmetry (Section 7 3) A point in the center of a structure located so that a line drawn from it to any element of the structure when extended an equal distance in the op posite direction encounters an identical element Benzene for example has a center of symmetry Cham reaction (Section 4 17) Reaction mechanism m which a sequence of individual steps repeats itself many times usu ally because a reactive intermediate consumed m one step is regenerated m a subsequent step The halogenation of alkanes is a chain reaction proceeding via free radical intermediates... 

Homolytic cleavage (Section 4 16) Dissociation of a two electron covalent bond in such a way that one electron is re tamed by each of the initially bonded atoms... 

Tanglefoot Tame acid Tank cars Tank cells Tanks... 

Ethers, such as MTBE and methyl / fZ-amyl ether (TAME) are made by a catalytic process from methanol (qv) and the corresponding isomeric olefin. These ethers have excellent octane values and compete on an economic basis with alkylation for inclusion in gasoline. Another ether, ethyl tert-huty ether (ETBE) is made from ethanol (qv) and isobutylene (see Butylenes). The cost and economic driving forces to use ETBE vs MTBE or TAME ate a function of the raw material costs and any tax incentives that may be provided because of the ethanol that is used to produce it. 

Some isopentane is dehydrogenated to isoamylene and converted, by processes analogous to those which produce methyl /-butyl ether [1634-04-4] (MTBE) to /-amyl methyl ether [994-05-8] (TAME), which is used as a fuel octane enhancer like MTBE. The amount of TAME which the market can absorb depends mostly on its price relative to MTBE, ethyl /-butyl ether [637-92-3] (ETBE), and ethanol, the other important oxygenated fuel additives. 

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