Inert solids, handling

The simplest technique is the use of the 96-well collection plate format (analogous to the format used in SPE) in conjunction with a liquid handling robotic system it follows the same principle as bulk scale LLE. However, immobilization of the aqueous plasma sample on an inert solid support medium packed in a cartridge or in the individual wells of a 96-well plate and percolating a water-immiscible organic solvent to extract the analyte from this medium evoked significant enthusiasm from the pharmaceutical industry. 

The stationary phase can be a liquid or a solid. If it is a liquid, it can be coated directly on the inside walls of a capillary tube (column), or it can be coated on an inert solid support and be handled like a solid. In effect, then, there are three stationary phase configurations in the first type, a solid (with or without stationary liquid) is packed into a column in the second type, a solid is coated on the surface of a flat, plane material like glass (TLC), and in the third type, a liquid is coated on the inside wall of an open tube (OT). 

Marrone et al. have described the numerous approaches that have been proposed for handling salts and inert solids in SCWO systems. In dealing with salts... 

The iron-amide complex is an extremely air- and moisture-sensitive light green solid and must be stored under a strictly inert atmosphere. Handling in a glovebox... 

Commercial Processes.. The Oxo reaction is carried out in the liquid phase. With gaseous olefins, a suspension medium such as an inert hydrocarbon is used of a boiling range sufiSciently different from the aldehyde product to allow easy separation. No additional medium is required for hydrofonnylation of liquid olefins. Two liquid-phase processes have been developed. In the earlier one the catalyst is slurried in the feedstock or added liquid medium. Less operating difiSculty is claimed for the newer fixed-bed system because the need for filtration and solids handling is eliminated. 

Carbon dioxide systems-Tliis system can be used where there is a handling and storage of gaseous and flammable materials, electrical equipment, and hazardous solids by introducing an inert gas (such as carbon dioxide) into the area in order to reduce the concentration of oxygen to the point where the fire will be extinguished. 

Addition of sodium hydride to a damp reactor which had not been pinged with inert gas caused evolution of hydrogen and a violent explosion. Solid dispersions of the hydride in mineral oil are more easily and safely handled [1], When an unprotected polythene bag containing the hydride was moved, some of the powder leaked from a hole, contacted moisture and immediately ignited. Such materials should be kept in tightly closed containers in an isolated, dry location [2],... 

Molybdenum (IV) bromide is a black crystalline solid which is very sensitive to oxidation and hydrolysis it should be handled only under a dry inert atmosphere. Its solubility in bromine at 51° is ca. 3.0 g./lOOO g. of bromine, and bromine solutions were found to be nonconductors. For example, at 25° both the solvent bromine and a 0.96 X 10 3 M solution in molybdenum (IV) bromide exhibited a specific conductance of 1.3 X 10-10 ohm-1 cm.-1 At 110 to 130° in vacuo, solid molybdenum (IV) bromide decomposes quantitatively into molyb-denum(III) bromide and bromine, and because of this thermal instability it cannot be sublimed except under a bromine atmosphere. 

A safe design for this operation includes closed handling of the solids and liquids in an inert atmosphere (see Figure 7-23). 

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