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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.
Reverse phase high-performance liquid chromatography (RP-HPLC) involves a non-polar stationary phase, often a hydrocarbon chain, and a polar mobile or liquid phase. The mobile phase generally consists of an aqueous portion with an organic addition, such as methanol or acetonitrile.
Modifying the polarity of a weakly ionic group (e.g. carboxyl) on the surface is easily accomplished by adjusting the pH to be within two pH units of that group's pKa. For strongly ionic functional groups of the surface (i.e. sulfates or phosphates) one could instead use a lower amount of buffer so the residual charge is not completely ion paired.
HPLC is widely used for manufacturing (e.g., during the production process of pharmaceutical and biological products), [4] [5] legal (e.g., detecting performance enhancement drugs in urine), [6] research (e.g., separating the components of a complex biological sample, or of similar synthetic chemicals from each other), and medical (e.g ...
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.
Thin-layer chromatography (TLC) is a chromatography technique that separates components in non-volatile mixtures. [1]It is performed on a TLC plate made up of a non-reactive solid coated with a thin layer of adsorbent material. [2]
Typical nitrile ligands are acetonitrile, propionitrile, and benzonitrile.The structures of [Ru(NH 3) 5 (NCPh)] n+ have been determined for the 2+ and 3+ oxidation states. Upon oxidation the Ru-NH 3 distances contract and the Ru-NCPh distances elongate, consistent with amines serving as pure-sigma donor ligands and nitriles functioning as pi-acceptors.
29.75 at 81.6 °C (BP) Std entropy change of vaporization, Δ vap S o: 111.44 J/(mol·K) at 25 °C Solid properties Std enthalpy change of formation, Δ f H o solid? kJ/mol at 25 °C Standard molar entropy, S o solid? J/(mol K) Heat capacity, c p: 92.36 J/(mol K)at 298.15 K Std enthalpy change of state transition, Δ trs H o: 0.8979 kJ/mol at ...