Cooling phenol hydrogenation

After three hours, on the average, the phenol has been completely evaporated and driven over the catalyst. When the receivers have been disconnected the hydrogen current is slowed down and the tube allowed to cool. The contents of the receivers are washed with a little ether into a small dropping funnel and shaken with 10 c.c. of 50 per cent sodium hydroxide solution in order to remove non-hydrogenated phenol. The solution is then decanted from the sodium phenoxide, which is washed with ether and dried with a little... 

Cool the alkaline solution resulting from the distillation of the volatile neutral compounds, make it acid to litmus with dilute sulphuric acid and add an excess of solid sodium hydrogen carbonate. Extract this hydrogen carbonate solution with two 20 ml portions of ether remove the ether from the combined ether extracts and identify the residual phenol (or enol). Then acidify the hydrogen carbonate solution cautiously with dilute sulphuric acid if an acidic compound separates, remove it by two extractions with 20 ml portions of ether if the... 

Distillate (S,). This will contain the volatile neutral components present. Concentrate by distillation and saturate with solid K2C03 the neutral component may separate. Aqueous alkaline solution. This will contain any acids or phenols present. Cool, acidify (litmus) with dilute H2S04, and add excess of solid NaHC03. Extract with ether. Ether Sodium hydrogen carbonate solution, solution. Acidify with dilute H2S04. Extract Contains with ether. phenolic compounds. Distillate. Extract with ether. Aqueous alkah ne solution (S2). Neutralise with dilute H2S04 (Congo red). Evaporate to dryness and extract with absolute ethanol. The alcoholic extract contains the water-soluble, non-volatile components. 

To vessel with flushed nitrogen at an elevated temperature to 165°C 490 parts of phenol was placed, then 4.5 parts of aluminum turnings were added in small increments.The reaction mixture was accompanied by evolution of hydrogen for 15 min, then the mixture was allowed to cool to about 60°C and agitation discontinued. Aluminum phenoxide catalyst mixture was ready. 

The impurities can be grouped into two categories lights (water, cyclohexene, cyclohexadiene) and heavies (phenol, dicyclohexyl-ether, cyclohexenyl- cyclohexanone). To limit their amount, the conversion is kept around 80% with a selectivity of about 98%. The hot reactor effluent is cooled in countercurrent with the feed in FEHE, and finally for phase separation in the heat exchanger (E-2) at 33 °C. The simple flash (S-2) can ensure a sharp split between hydrogen, recycled to hydrogenation reactor, and a liquid phase sent to separation. 

Heat a few milligrams of the solid unknown with 10-20 mg of potassium hydrogen sulphate and 2 drops of concentrated sulphuric acid in a small porcelain crucible, allow to cool, and add a few milligrams of solid phenol. A red colouration is produced. 

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