Routine glassware

A typical bench set of routine glassware, excluding specialized equipment, is given below. 

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There are certain items which individuals usually prefer to keep for their own personal use, even when routine glassware is communal. Here is a list of standard, commercially-available items which we think should be kept as the bench kit ... 

If the distillation is not carried out promptly, the crude product should be placed under nitrogen in a freezer. The tetralone seems to keep better under nitrogen at low temperature in glassware that has been rinsed with ammonium hydroxide and dried in an oven the distillation fiask and column were also routinely treated this way. 

All glassware, syringes and cannulae were routinely flame- or oven-dried and cooled under dry nitrogen. 

Fig. 2. Simple glassware washer. The diagram shows a simple spinning-brush washing attachment (Southern Cross), which facilitates routine washing procedures. Other brushes are also supplied for variously shaped glassware.

Do not bake reusable glassware as a routine part of cleaning. Baking may be warranted after particularly dirty samples are encountered, but should be minimized, as repeated baking may cause active sites on the glass surface that will irreversibly adsorb PCDDs/PCDFs. 

All reactions and sample preparations are carried out in an inert-atmosphere enclosure under dry nitrogen. Solvents and reagents are dried in the following manner. Benzene, tetrahydrofuran, and n-pentane are freshly distilled from lithium aluminum hydride pyridine is distilled over barium oxide and tetramethylethylenediamine is distilled over calcium hydride. Solvents used in preparing nmr and infrared samples are degassed by a freeze-thaw technique. Nmr spectra are obtained with torch-sealed nmr tubes. The commercial transition metal carbonyl complexes are recrystallized and vacuum-dried before use. Glassware is routinely flame-dried. 

Glassware used routinely in the laboratory is easily contaminated by traces of metallic elements which become adsorbed onto the surface of the glass. They are not easily removed by ordinary washing. To remove previous contamination and prevent it from invalidating the results, the... 

Water Reduction. The principle weakness of cannula techniques is that small volumes of solution can be exposed to large surface areas of glass and steel. These are major sources of water contamination, and we routinely oven dry all transfer cannulae and glassware before use. 

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