Distillation adapter, vacuum

The dotted line in Fig. 11,17, 2 refers to the modification of the apparatus for use in fractional distillation under reduced pressure a Perkin triangle or equivalent receiver device ( vacuum distilling adapter ) is generally employed for collection of the various fractions. 

Attach the flask containing the mixture, with capillary in position, to the column make sure that the Perkin triangle (or vacuum distilling adapter ) and receiver are in place. See that the oil pump is functioning... 

The vacuum distillation adapter also shown in Fig. 2.106 allows the collection of fractions when distilling under reduced pressure. Its operation is similar to the Perkin triangle or equivalent device ( intermediate receiver adapter ) described in Section 2.27. The general technique of conducting a fractional distillation is as follows ... 

Prelab Exercise Study the glassware diagrams and be prepared to identify the fractionating column, Claisen distilling hjead, ordinary distilling head, vacuum adapter, simple bent adapter, calcium chloride tube, Hirsch funnel, and Buchner funnel. 

Hence, a prepolymer of poly(hexamethylene carbonate) was formed by adding to a flame dried 250 ml single neck flask 36.6 g of 1,6-hexanediol and 69.2 g of diphenyl carbonate. The flask was fitted with a mechanical stirrer, a distillation adapter and recehing flask. The reaction flask was held under high vacuum at room temperature... 

Some simple apparatus, suitable for high vacuum distillation, are collected in Figs. 11, 26, 1-4. Fig. 11, 26, 1 represents an apparatus, which is particularly well adapted for solids the ground glass joint must be lubricated with a grease of negligible vapour pressure. Hickman s vacuum still is shown in Fig. 11, 26, 2 it is about 60 mm. in diameter. 

Setup your glassware for simple distillation with a claisen adapter, three way adapter, pressure-equalized addition funnel, water cooled condenser, vacuum adapter and receiver flask to catch any condensed solvent vapors. 

The cmsts from the Parkes process are then treated to recover the 2inc contained in the dross for reuse in desi1veri2ing This is done by distillation (qv) and more commonly by vacuum technology. A continuous adaptation of the Parkes process is carried out at The Broken Hill Associated Smelters Pty. (Port Pide, AustraUa). The chemistry of this operation is the same as that for batch desi1veri2ing (22,23). 

Later it was synthesized in a batch process from dimethyl ether and sulfur thoxide (93) and this combination was adapted for continuous operation. Gaseous dimethyl ether was bubbled at 15.4 kg/h into the bottom of a tower 20 cm in diameter and 365 cm high and filled with the reaction product dimethyl sulfate. Liquid sulfur thoxide was introduced at 26.5 kg/h at the top of the tower. The mildly exothermic reaction was controlled at 45—47°C, and the reaction product (96—97 wt % dimethyl sulfate, sulfuhc acid, and methyl hydrogen sulfate) was continuously withdrawn and purified by vacuum distillation over sodium sulfate. The yield was almost quantitative, and the product was a clear, colorless, mobile Hquid. A modified process is deschbed in Reference 94. Properties are Hsted in Table 3. 

The following steps are performed in an argon atmosphere glovebox. In a 50-mL round-bottom flask equipped with a Teflon magnetic stirbar, 2.03 g (14.7 mmol) of previously distilled and degassed 1,9-decadiene (9) (Aldrich) and 27.6 mg (3.61 x 10 2 mmol) of Schrock s catalyst (14) (400 1) are combined. In a matter of seconds, the catalyst is dissolved into the monomer and a vigorous evolution of ethylene is observed. The flask is sealed with a Teflon vacuum adapter and removed from the box. The polymerization vessel is immediately connected to the vacuum line, placed into an oil bath, and stirred at 30°C. Intermittent vacuum... 

VRDS Isomax [Vacuum residua desulphurization] A hydrodesulfurization process adapted for processing the residues from the vacuum distillation of the least volatile fraction of petroleum. An extension of the RDS Isomax process, developed and piloted by Chevron Research Company in the early 1970s. In 1988, one unit was under construction and one was being engineered. 

Fig. 78 A Clalsen adapter so you can vacuum distill and take temperatures too.

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