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If they are above these levels the waste must be taken to a hazardous waste disposal facility and the cost of disposal may increase from about $50.00/ton to as much as $1200.00/ton. As extremely contaminated material is expensive to dispose of, grading is necessary to ensure safe disposal and to avoid paying for disposal of "clean fill."
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.
HPLC has many applications in both laboratory and clinical science. It is a common technique used in pharmaceutical development, as it is a dependable way to obtain and ensure product purity. [59] While HPLC can produce extremely high quality (pure) products, it is not always the primary method used in the production of bulk drug materials. [60]
Silica gel particles are commonly used as a stationary phase in high-performance liquid chromatography (HPLC) for several reasons, [13] [14] including: High surface area: Silica gel particles have a high surface area, allowing direct interactions with solutes or after bonding of variety of ligands for versatile interactions with the sample molecules, leading to better separations.
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).
Other salts, such as 100–300 mM sodium perchlorate, that are soluble in high-organic solvent mixtures (c. 70–90% acetonitrile), can be used to increase the mobile phase polarity to affect elution These salts are not volatile, so this technique is less useful with a mass spectrometer as the detector. Usually a gradient (to increasing amounts ...
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.
Acetamidine hydrochloride is synthesised in a two-step process that begins with a solution of acetonitrile in ethanol at close to 0 °C. [4] First, the mixture is treated with anhydrous hydrogen chloride in a Pinner reaction, producing crystals of acetimido ethyl ether hydrochloride: H 3 C−C≡N + C 2 H 5 OH + HCl → H 3 C−C(=NH·HCl)−OC ...