Binary mixtures sulfuric acid concentration

B. Ethyl a-(bromomethyl)acry late. In a nitrogen-flushed, 1-L, round-bottomed flask equipped with a magnetic stirrer, Dean-Stark trap, and condenser are placed 42.0 g (0.25 mol) of a-(bromomethyl)acrylic acid and 300 mL of benzene. Approximately 50 mL of a binary azeotrope of benzene and water is distilled (Note 7). The Dean-Stark trap is removed and 100 mL of absolute ethanol (Note 8) and 1 mL of concentrated sulfuric acid are added slowly. The contents of the flask are boiled in a nitrogen atmosphere for 36 hr, the condensate being passed through 100 g of molecular sieves (Linde 3A) before being returned to the flask. About 125 mL of a mixture of benzene and ethanol is removed from the reaction... 

Applications in the eutectic mixture Seuk et al. [61], Rai et al. [62] also proposed a new binary eutectic mixture F/DF, namely BDNPF/BDNPDF (bis-2,2-dinitropropyl dimethyl acetal), can be prepared from DNPOH and formaldehyde with concentrated sulfuric acid added to the raw material at a low temperature. F/DF has good chemical and thermal stability with low cost, and does crystallize for long-term storage even at -20 °C. 

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