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Acetonitrile is used mainly as a solvent in the purification of butadiene in refineries. Specifically, acetonitrile is fed into the top of a distillation column filled with hydrocarbons including butadiene, and as the acetonitrile falls down through the column, it absorbs the butadiene which is then sent from the bottom of the tower to a second separating tower.
Mobile phases for ANPC are based on organic solvents as bulk solvents (such as methanol or acetonitrile) with a small amount of water as a modifier of polarity; thus, the mobile phase is both "aqueous" (water is present) and "normal phase type" (less polar than the stationary phase).
[7] [27] The added organic solvents must be miscible with water, and the two most common organic solvents used are acetonitrile and methanol. Other solvents can also be used such as ethanol or 2-propanol (isopropyl alcohol) and tetrahydrofuran (THF). The organic solvent is called also a modifier, since it is added to the aqueous solution in the ...
In chemistry a donor number (DN) is a quantitative measure of Lewis basicity.A donor number is defined as the negative enthalpy value for the 1:1 adduct formation between a Lewis base and the standard Lewis acid SbCl 5 (antimony pentachloride), in dilute solution in the noncoordinating solvent 1,2-dichloroethane with a zero DN.
In the laboratory, triflic acid is useful in protonations because the conjugate base of triflic acid is nonnucleophilic. It is also used as an acidic titrant in nonaqueous acid-base titration because it behaves as a strong acid in many solvents (acetonitrile, acetic acid, etc.) where common mineral acids (such as HCl or H 2 SO 4) are only moderately strong.
A polar aprotic solvent is a solvent that lacks an acidic proton and is polar. Such solvents lack hydroxyl and amine groups. In contrast to protic solvents, these solvents do not serve as proton donors in hydrogen bonding, although they can be proton acceptors.
In the laboratory, the reduction of the nitroaniline is effected with zinc powder in ethanol, followed by purification of the diamine as the hydrochloride salt. Darkened impure samples can be purified by treatment of its aqueous solution with sodium dithionite and activated carbon. [5]
Hydrogenation of acetonitrile, acetamide, and nitroethane affords ethylamine. These reactions can be effected stoichiometrically using lithium aluminium hydride . In another route, ethylamine can be synthesized via nucleophilic substitution of a haloethane (such as chloroethane or bromoethane ) with ammonia , utilizing a strong base such as ...